,z ! ,nation's pr9cipal cons]vation ag5cy1 ! ,dep>tm5t ( ! ,int]ior has basic responsibilities = wat]1 fi%1 wildlife1 m9]al1 l&1 p>k1 & recreational res\rces4 ,indian & ,t]ritorial affairs are o!r major conc]ns ( ,am]ica's 8,dep>tm5t ( ,natural ,res\rces40 ,! ,dep>tm5t works to assure ! wise/ *oice 9 manag+ all our res\rces s ea* w make its full contribution to a bett] ,unit$ ,/ates--n[ & 9 ! future4 ,?is publication is "o 9 a s]ies ( rese>* /udies devot$ to special topics :i* h be5 explor$ 9 connection ) ! v>i\s areas 9 ! ,national ,p>k ,sy/em4 ,x is pr9t$ at ! ,gov]nm5t ,pr9t+ ,(fice & may be pur*as$ f ! ,sup]9t5d5t ( ,docum5ts1 ,gov]nm5t ,pr9t+ ,(fice1 ,wa%+ton1 ,d4,c4 #bjdjb4 ,libr>y ( ,congress ,catalog+ 9 ,publication ,data ,mc,grew1 ,paul ,orman1 #aiji- ,! geological hi/ory ( ,fossil ,butte ,national ,monum5t & ,fossil ,bas94 7,national ,p>k ,s]vice occasional pap]2 no4 #c7 ,bibliography3 p4 ,includes index4 #a4 ,geology--,wyom+--,fossil ,butte ,national ,monum5t4 #b4 ,geology1 ,/ratigraphic--,eoc5e4 #c4 ,paleontology--,eoc5e4 #d4 ,fossil ,butte ,national ,monum5t1 ,wyo4 ,i4 ,casilliano1 ,mi*ael1 jo9t au?or4 ,,ii4 ,title4 ,,iii4 ,s]ies3 ,unit$ ,/ates4 ,national ,p>k ,s]vice4 ,national ,p>k ,s]vice occasional pap]2 no4 #c4 ,,qe#ahb4;,f#fg,m#c #eeg4hg'hb #ge-ageaa ,! ,geological ,hi/ory ( ,fossil ,butte ,national ,monum5t & ,fossil ,bas9 ,paul ,o4 ,mc,grew ,mi*ael ,casilliano ,dep>tm5t ( ,geology1 ,univ]sity ( ,wyom+ ,,national ,,p>k ,,s]vice ,,occasional ,,pap] ,,numb] ,,?ree ,illu/ration3 ,excavations 9 progress ,cont5ts ,,introduction #a ,,location #a ,,hi/orical ,,backgr\nd ,,( ,,rese>* #a ,,/ratigraphy #e ,?aynes ,lime/one #g ,evan/on ,=mation #g ,wasat* ,=mation #g ,basal ,conglom]ate ,memb] #i ,l[] ,memb] #i ,ma9 ,body #aa ,s&/one ,tongue #aa ,mud/one ,tongue #ab ,bullp5 ,memb] #ab ,tunp ,memb] #ab ,age ( ! ,wasat* ,=mation #ab ,depositional ,environm5t #ac ,gre5 ,riv] ,=mation #ac ,fossil ,butte ,memb] #ac ,angelo ,memb] #ad ,age ( ! ,gre5 ,riv] ,=mation #ad ,depositional ,environm5t #ad ,f[kes ,=mation #ae ,sillem ,memb] #ae ,bulldog ,holl[ ,memb] #ae ,gooseb]ry ,memb] #ae ,age ( ! ,f[kes ,=mation #ae ,depositional ,environm5t #ae ,,quat]n>y #ae ,,! ,,geologic ,,/ructure ,,( ,,fossil ,,bas9 #ae ,,paleontology #ai ,flora #ai ,inv]tebrates #bj ,v]tebrates #bj ,fi% #bj ,amphibians #bd ,reptiles #bd ,birds #bd ,mammals #be ,,paleoecology ,,& ,,taphonomy #cj ,,gloss>y #cd ,,ref]5ces #ce ,,bibliography #cg ,,ackn[l$gm5ts #cg ,,introduction ,fifty million ye>s ago ! s\?we/]n corn] ( :at is n[ ,wyom+ 0 "p ( a sy/em ( ?ree fre%wat] lakes t cov]$ t area plus adjac5t p>ts ( ,colorado & ,utah4 ,^! lakes began ) ,lake ,flag/aff & lat] became ,lake ,gosiute1 ,lake ,u9ta1 & ,fossil ,lake 7,fig4 #a74 ,^! lakes develop$ 9 int]montane bas9s t 7 creat$ z a result ( ! geologic ev5ts t =m$ ! ,rocky ,m\nta9s4 ,! ?ree lakes1 collectively kn[n z ! ,gre5 ,riv] ,lake ,sy/em1 _h a long1 complex hi/ory ( expansion & contraction4 ,v>y+ climatic & geologic conditions 7 responsible = ! *anges 9 lake size & di/ribution4 ,! %ores surr\nd+ ! lakes 7 blanket$ by a lu%1 gre5 canopy ( palm1 c9namon1 maple1 oak1 & o!r famili> trees4 ,hazel & lilac cov]$ ! =e/ floor4 ,ru%es & o!r aquatic plants l9$ ! lake %ore4 ,! air 0 humid & w>m4 ,/reams fl[+ d[n f ! hills & m\nta9s built up flood pla9s & f$ s$im5t into ! lake1 :]e x 0 deposit$ 9 %all[ wat] ne> ! %ore4 ,deposits =m$ by *emical processes settl$ to ! bottom fur!r f %ore 9 deep1 quiet wat]4 ,f ^! processes 7 =m$ ! rocks f :i* ! pa/ hi/ory ( ,gre5 ,riv] ,lake ,sy/em is read4 ,9 ! =e/ & und]gr[? liv$ ! ance/ors ( mod]n mammal gr\ps4 ,ance/ral rod5ts & t9y insectivores liv$ a furtive exi/5ce 9 ! bru% & mold t c>pet$ ! =e/ floor1 or else !y s\ght a livelihood among ! bran*es ( trees4 ,l>ge1 biz>re animals ) /range names lumb]$ ?r\gh ! re$-cov]$ /reamsides eat+ s(t1 succul5t plants4 ,! e>lie/ memb]s ( ! horse family br[s$ on ! s(t vegetation4 ,! trees ov]head 7 alive ) ! *att]+ & antics ( e>ly primates4 ,c>nivor\s mammals prey$ on _! plant-eat+ neighbors & s ma9ta9$ a balanc$ community4 ,crocodiles & turtles bask$ 9 ! sun on ! bea*4 ,flam+os conc5trat$ 9 l>ge ne/+ gr\nds4 ,snakes & liz>ds crawl$ ab\t 9 ! und]gr[?4 ,insects1 _m exce$+ly simil> to mod]n types1 flew ab\t 9 ! w>m air or crept ab\t on ! plants4 ,! wat]s ( ! lakes teem$ ) _m types ( fi%4 ,relatives ( ! p]*1 h]r+1 & /+ ray swam 9 ! w>m lake wat]4 ,occasionally1 l>ge-scale mortalities ( ! fi% occurr$4 ,z ! fi% di$1 !y sank to ! bottom ( ! lake1 & 7 pres]v$ 9 ! lake s$im5ts4 ,today1 ! lakes are gone & :]e once !re 7 lu% tropical =e/s !re is n[ a semi-des]t cov]$ ) sagebru% & greasewood4 ,! hi/ory ( ^! lakes1 =e/s1 & animal life c be read 9 ! ?ick s$im5ts deposit$ s long ago4 ,?is report conc]ns itself ) "o ( ^! lakes1 ! smalle/ ( ! ?ree1 ,fossil ,lake4 ,fam\s = its fossil fi% b$s1 "p ( ?is anci5t lake is n[ ,fossil ,butte ,national ,monum5t4 ,x is ! purpose ( ?is report to relate ! hi/ory ( ,fossil ,lake & its n[ fossiliz$ inhabitants1 !reby1 hopefully pres5t+ ! ord] ( ev5ts 9 a l&scape obscur$ by #ej million ye>s ( "t4 ,,location ,fossil ,butte ,national ,monum5t is ne> ! geographical c5t] ( ,fossil ,bas94 ,! bas9 itself is locat$ 9 ! extreme s\?we/]n "p ( ,wyom+ 9 ,u9ta & ,l9coln c\nties1 ne> ! ,utah-,idaho bord] 7,fig4 #b74 ,! monum5t is situat$ ab\t #aj miles we/ ( ,kemm]]1 ,l9coln ,c\nty1 ,wyom+ 7,fig4 #c74 ,u4,s4 ,highway #cj,n runs j s\? ( ! monum5t z does ! ,union ,pacific ,railroad l9e to ,oregon4 ,! ab&on$ t[n ( ,fossil is also imm$iately s\? ( ! monum5t4 ,! ,kemm]] & ,sage quadrangles ( ! ,unit$ ,/ates ,geological ,survey cov] ! entire monum5t & ! surr\nd+ area4 ,,hi/orical ,,backgr\nd ,,( ,,rese>* ,! pr9cipal rocks involv$ at ,fossil ,butte are ! ,gre5 ,riv] & ,wasat* =mations4 ,! fir/ publi%$ notice ( ^! two rock units 0 by ,hayd5 7#ahfi74 ,al?\gh %ort1 ,hayd5's descriptions 7 ! basis = lat] ref9em5t ( ! /ratigraphy ( ! ,gre5 ,riv] & ,fossil bas9s4 ,hayd5 also m5tion$ ! quantities ( fossil fi% f ! ,gre5 ,riv] ,=mation4 ,! "w done by ,hayd5 0 conduct$ "u ! auspices ( ! ,u4,s4 ,dep>tm5t ( ! ,int]ior1 ,geological & ,geographical ,survey ( ! ,t]ritories4 ,! survey la/$ f #ahfg to #ahgh1 dur+ :i* "t ,hayd5 & 8 associates publi%$ annual reports ( _! f9d+s4 ,9 ! #ahgj report1 ,hayd5 7#ahga7 m5tion$ ! discov]y ( ! ,petrifi$ ,fi% ,cut4 ,?is cut is locat$ on ! ma9 l9e ( ! ,union ,pacific ,railroad ab\t #b miles we/ ( ,gre5 ,riv]1 ,wyom+4 ,a4 ,w4 ,hilli>d & ,l4 ,e4 ,rickseek]1 employees ( ! ,union ,pacific ,railroad1 discov]$ ! cut & obta9$ _m fossil fi% :i* !y turn$ ov] to ,hayd54 ,previ\s to ,hayd51 rocks n[ kn[n z ! ,gre5 ,riv] & ,wasat* =mations 7 occasionally m5tion$ 9 ! v>i\s di>ies1 j\rnals1 & reports ( e>ly mission>ies l ^? ( ,s4 ,a4 ,p>k] or ^? ( explor]s l ,fremont 7,knight #aiee74 ,illu/ration3 ,fig4 #a4 ,paleoc5e-,eoc5e lake sy/em 7aft] ,s*aeff] & ,mangun #aife74 ,illu/ration3 ,fig4 #b4 ,geographic features ( s\?we/ ,wyom+ & adjac5t areas 7f ,oriel & ,tracey #aigj74 ,illu/ration3 ,fig4 #c4 ,physiography ( ! ,fossil ,butte ,national ,monum5t region 7f ,u4,s4 ,dep>tm5t ( ! ,int]ior #aifd74 ,hayd5's report 7#ahga3dbe-dcg7 includ$ a description ( ! fi% fossils f ,petrifi$ ,fi% ,cut by ,e4 ,d4 ,cope1 a v]tebrate paleontologi/4 ,sev]al ye>s e>li] ,leidy 7#ahef71 ano!r paleontologi/1 describ$ a fi% f an unkn[n locality 9 ! ,gre5 ,riv] ,=mation4 ,hayd5 divid$ ?is survey area into sev]al di/ricts4 ,! ,gre5 ,riv] di/rict 0 put 9 *>ge ( ,a4 ,c4 ,peale4 ,peale's 7#ahgi3ece7 report conta9$ ! fir/ geologic description ( ,fossil ,butte itself1 z well z a %ort discussion ( ! fi% fossils obta9$ !re4 ,! description ( ! butte is quot$ "h3 444 ,9 ! l[] "p ( ! bluff f :i* ^! specim5s are tak51 ! bright col\r$ b$s ( ! ,wasat* are se5 outcropp+1 al?\gh ! entire section _c be se51 z _! s(tness causes !m to wea!r s t ! debris conceals ! /rata4 ,! fossils are f\nd at sev]al horizons 9 ! %ales4 ,ne> ! top ( ! bluff is a b& ( h>d1 bitum9\s1 or oily %ale1 :i* burns r freely ) a /rong bitum9\s odor4444 ,x is br[ni%-black 9 color & on ! wea!r$ surfaces a blui% :ite4444 ,! next major publication deal+ ) ,fossil ,bas9 0 t by ,veat* 7#aijg74 ,he mapp$ ! rocks 9 c]ta9 areas ( ! bas9 9 an attempt to br+ a semblance ( ord] to ,hayd5's 7#ahfi7 broad /ratigraphic descriptions4 ,8 "w result$ 9 ! designation ( mo/ ( ! rock units 9 ,fossil ,bas9 f ,jurassic to ,rec5t4 ,s*ultz 7#aiad71 an associate ( ,veat*1 publi%$ a pap] deal+ ) ! /ructures to ! nor? & ea/ ( ,fossil ,bas94 ,?is help$ to del9eate ! features surr\nd+ & =m+ ! bas94 ,subsequ5t "w on ! geology ( s\?we/ ,wyom+ ma9ly has be5 conc5trat$ on ! ,gre5 ,riv] ,bas9 j ea/ ( ,fossil ,bas94 ,significant "w on ,fossil ,bas9 has be5 done by ,rubey et al4 7#aifh;a1 b7 :o mapp$ ! nor!rn "p ( ! bas91 & by ,oriel & ,tracey 7#aigj7 :o h publi%$ results ( ! late/ /udy on ! /ratigraphy & age ( ! rock units 9 ,fossil ,bas94 ,?is late/ "w is ! culm9ation ( _m ye>s ( /udy & incorporates & ref9es data pres5t$ 9 %ort]1 e>li] pap]s4 ,,/ratigraphy ,! complete geologic hi/ory ( ! ,fossil ,bas9 involves _m /ratigraphic units4 ,mo/ ( ^! are n expos$ )9 ! monum5t itself b are well kn[n f outcrops outside ! b\nd>ies ( ! monum5t & f deep wells 7,fig4 #d74 ,at ! base ( ! /ratigraphic section are rocks ( ,precambrian age4 ,^! h n be5 p5etrat$ by wells )9 ! ,fossil ,bas9 b %\ld occur z mu* z #be1jjj ft b5ea? ! surface4 ,!y probably consi/ ( metamorphic & intrusive rocks4 ,beg9n+ ab\t #fjj million ye>s ago1 at ! beg9n+ ( ,cambrian "t1 s$im5t>y deposits accumulat$4 ,^! are bo? m>9e & cont95tal 9 orig9 & range 9 age f e>ly ,cambrian 7#fjj million ye>s old7 to e>ly ,t]ti>y 7#ej million ye>s old74 ,"s #cd geologic =mations are recogniz$ 9 ?is ?ick section1 a li/ ( :i* foll[s3 ,eoc5e ,f[kes ,=mation ,wasat*-,gre5 ,riv] ,=mations ,paleoc5e ,evan/on ,=mation 7upp] "p7 ,upp] ,cretace\s ,evan/on ,=mation 7l[] "p7 ,adaville ,=mation ,laze>t ,s&/one ,hilli>d ,%ale ,fronti] ,=mation ,l[] ,cretace\s ,asp5 ,%ale ,be> ,riv] ,=mation ,gannett ,gr\p ,jurassic ,/ump ,s&/one ,preuss ,s&/one ,tw9 ,creek ,lime/one ,nugget ,s&/one 7upp] "p7 ,triassic ,nugget ,s&/one 7l[] "p7 ,?aynes ,lime/one ,woodside ,=mation ,d9woody ,=mation ,p]mian ,phosphoria ,=mation ,p5nsylvanian ,wells ,=mation ,mississippian ,braz] ,lime/one ,madison ,lime/one 7upp] "p7 ,devonian ,madison ,lime/one 7l[] "p7 ,d>by ,=mation ,silurian ,n ,pres5t ,ordovician ,leigh ,dolomite ,bighorn ,dolomite ,cambrian ,gallat9 ,lime/one ,gros ,v5tre ,=mation ,precambrian ,complex ( metamorphic & intrusive rocks ,)9 ! monum5t itself ! olde/ rocks expos$ are ^? ( ! ,?aynes ,lime/one ne> ,pr[ ,po9t4 ,z w be se5 9 ! discussion ( ! /ructure ( ! ,fossil ,bas91 all ( ! rocks b5ea? ! ,evan/on ,=mation are fold$ & fault$ & )9 ! monum5t are buri$ by deposits ( ,t]ti>y age4 ,= ?is reason detail$ discussion ( /ratigraphic units w be conf9$ to ^? rocks t c be se5 )9 ! b\nd>ies ( ! monum5t or closely adjac5t to x 7,fig4 #e 74 ,! di/ribution ( ! v>i\s =mations )9 ! monum5t is illu/rat$ 9 ,figs4 #g & #h4 ,illu/ration3 ,fig4 #d4 ,geologic "t scale4 ,era_/,p]iod_/,epo* ,age ,major ,biological ,geologic ,ev5ts 7,millions ( ye>s7 ,,c5ozoic ,quat]n>y ,ice ,age beg9s & evolution ( mod]n mammals2 man rea*es ,n4 ,a42 g5]al uplift ( cont95t4 ,holoc5e 7,rec5t7 4#ja ,plei/oc5e #c ,t]ti>y ,evolution & ,developm5t ( major mammal gr\ps2 ,cascadian ,orog5y 9 nor?we/]n ,unit$ ,/ates2 9 late/ ,c5ozoic1 ,eoc5e lake sy/em4 ,plioc5e #e4e ,mioc5e #be4e ,oligoc5e #cf ,eoc5e #ed ,paleoc5e #fe ,,mesozoic ,cretace\s #acj ,ext9ction ( d9osaurs2 fl[]+ plants fl\ri%2 height ( ,cordill]an ,orog5y4 ,jurassic #ahe ,fir/ birds1 d9osaurs & mammals cont9ue to evolve2 beg9n+ ( ,cordill]an ,orog5y :i* =m$ ! ,rocky ,m\nta9s4 ,triassic #bcj ,conif]s evolv$2 fir/ d9osaurs2 fir/ mammals2 ,appala*ian ,orog5y2 "s orog5y 9 ,cordill]a4 ,,paleozoic ,p]mian #bfe ,ar*aic reptiles & mammal-l reptiles evolve4 ,appala*ian ,orog5y4 ,p5nsylvanian #caj ,fir/ reptiles1 coal swamps =m$2 beg9n+ ( ! ,appala*ian ,orog5y4 ,mississippian #cee ,expansion ( amphibians2 mu* c>bonate deposition2 ,antl] ,orog5y 9 ,cordill]an ,mobile ,belt 7,rocky ,m\nta9 area74 ,devonian #dac ,fir/ l& plants2 fir/ jaw$ fi%es1 %>ks & bony fi%2 amphibians appe>2 ,acadian ,orog5y 9 ! ,appala*ian belt4 ,silurian #dbe ,jawless fi%es evolv$2 mu* reef developm5t2 evaporite m9]al developm5t4 ,ordovician #dge ,fir/ v]tebrate rema9s kn[n f ?is "t2 ,taconic ,orog5y 9 ,appala*ian belt4 ,cambrian #fjj ,fir/ %ell$ inv]tebrates2 major flood+ ( ,nor? ,am]ica4 ,notes3 ,re=matt$ table to comb9e #8,era'1 #8,p]iod'1 & #8,epo*' columns into "o column 9 outl9e =m4 ,b5ea? head+ #8,epo*'3 87,c5ozoic only702 beside o!r p]iods1 8,epo*s = ^! p]iods are n def9itely e/abli%$0 ,z ! la/ l9e1 8,precambrian "t began #e billion ye>s ago40 ,?aynes ,lime/one ,at ! v nor!a/]n corn] ( ,fossil ,butte ,national ,monum5t c be se5 an outcrop ( ! ,?aynes ,lime/one ( ,triassic age1 a m>9e unit deposit$ "s #bjj million ye>s ago4 ,?is =mation is not$ = its ri* & v>i$ assemblage ( m>9e fossils1 mo/ly =ms relat$ to oy/]s & clams4 ,! ,?aynes ,lime/one consi/s pr$om9antly ( s&y1 gray lime/one & gre5-gray limey silt/ones4 ,! =mation wea!rs to a d>k br[n 9 ! l[] "p & a grayi%-yell[ 9 ! upp]4 ,! fact t ! ,?aynes ,lime/one is expos$ 9 ! monum5t at all is because ( ! fault+ t took place j prior to ! deposition ( ! ,evan/on ,=mation ( late/ ,cretace\s & e>lie/ ,t]ti>y age 7ref] to section on /ructure7 & ! erosion ( ! ,t]ti>y rocks t once cov]$ x4 ,evan/on ,=mation ,al?\gh n se5 )9 ! b\nd>ies ( ! ,fossil ,butte ,national ,monum5t1 ! ,evan/on ,=mation is expos$ j s\? ( ,highway #cj,n1 #a4e miles s\!a/ ( ! s\!a/ corn] ( ! monum5t4 ,! ,evan/on 0 n involv$ 9 ! complex fold+ & fault+ b x is some:at di/urb$ & re/s "u ! ,wasat* ,=mation ) angul> uncom=mity4 ,! ,evan/on ,=mation bridges ! "t b\nd>y betwe5 ! ,cretace\s & ,t]ti>y p]iods4 ,9 ! l[] "p ( ! unit are f\nd _m fossil leaves1 poll51 & spores & a jaw ( ! horn$ d9osaur ,tric]atops t prove its ,cretace\s age1 & 9 ! upp] "p are f\nd fossil mammals ( ,paleoc5e age4 ,! ,evan/on ,=mation has be5 /udi$ 9 detail by ,oriel & ,tracey 7#aigj74 ,^! au?ors divide ! =mation into ?ree memb]s4 ,! l[e/1 :i* !y call$ ! ,l[] ,memb]1 is pr$om9antly 8gray to v d>k gray mud/one1 silt/one1 clay/one & gray c>bonace\s s&/one40 ,! ,l[] ,memb] rea*es a ?ickness ( #ejj ft 9 "s places4 ,above & 9 "p int]f+]+ ) ! ,l[] ,memb] is a #ajjj ft ?ick unit t 0 nam$ ! ,hams ,=k ,conglom]ate ,memb]4 ,?is unit consi/s ( b$s ( b\ld] conglom]ate int]/ratifi$ ) ?ick b$s ( co>se1 p>tly conglom]atic br[n s&/one & gray mud/one4 ,:]e ! ,l[] ,memb] ( ! ,evan/on is miss+1 ! ,hams ,=k ,conglom]ate =ms ! base ( ! =mation4 ,! ,upp] ,memb] ( ! ,evan/on ,=mation is t]m$ by ,oriel & ,tracey 7#aigj7 ! ,ma9 ,body4 ,x is m ?an a ?\s& feet ?ick & ! l[] "p int]tongues ) ! ,hams ,=k ,conglom]ate4 ,! ,ma9 ,body is 8light to d>k gray c>bonace\s s&y to clayey silt/one int]b$d$ ) gray1 tan1 yell[ & br[n s&/one & conglom]ate & c>bonace\s to lignitic clay/one40 ,x is ?is ,ma9 ,body t c be se5 along ! highway j s\!a/ ( ! monum5t4 ,! types ( s$im5ts & fossils f\nd 9 ! ,evan/on indicate t ! =mation 0 deposit$ by /reams on flood pla9s & 9 m>%es & ponds4 ,a subtropical climate is indicat$ & ! area 0 heavily wood$4 ,wasat* ,=mation ,! t]m ,wasat* 0 fir/ us$ by ,hayd5 7#ahfi3ia7 z foll[s3 ,imm$iately we/ ( ,=t ,bridg] comm5ces "o ( ! mo/ rem>kable & ext5sive gr\ps ( ,t]ti>y b$s se5 9 ! ,we/4 ,!y are wond]fully v>iegat$1 "s %ade ( r$ pr$om9at+4 ,?is gr\p1 to :i* ,i h giv5 ! "n ( ,wasat* gr\p1 is compos$ ( v>iegat$ s&s & clays4 ,v little calc>e\s matt] is f\nd 9 ^! b$s4 ,9 ,e*o & ,web] ,canyons are wond]ful displays ( conglom]ates1 fifte5 hundr$ to two ?\s& feet 9 ?ickness4 ,al?\gh ?is gr\p occupies a va/ area1 & atta9s a ?ickness ( ?ree to five ?\s& feet1 yet ,i h nev] kn[n any rema9s ( animals to be f\nd 9 x4 ,i reg>d x1 h[ev]1 z ( middle ,t]ti>y age4 ,! ,wasat* is well expos$ 9 ,fossil ,bas94 ,!re ! unit 0 reg>d$ by ,veat* 7#aijg7 z a gr\p & divid$ by him into ?ree =mations3 ! ,almy1 ,f[kes1 & ,knight4 ,he wrote 7#aijg3hh73 ,9 ! ,wasat* gr\p z ?us def9$ by ,hayd5 ! field "w ( ! season #aije %[$ ?ree divisions3 #a7 a basal memb] compos$ ( r$di%-yell[ s&y clays1 9 _m places conta9+ pron\nc$ conglom]ate b$s1 :i* has be5 nam$ ! ,almy ,=mation2 #b7 a great ?ickness ( light-color$ rhyolitic a% b$s conta9+ int]calat$ l5ses ( :ite lime/ones ) fre%-wat] %ells & leaves--! ,f[kes ,=mation2 & #c7 a gr\p ( r$di%-yell[ s&y clays ) irregul> s&/one b$s 7! ,knight ,=mation7 closely resembl+ #a7 li?ologically & sep>at$ f #a7 #b7 by a pron\nc$ p]iod ( fold+ & erosion4 ,veat*1 h[ev]1 err$ 9 8 field "w & did n realize t ! ,f[kes ,=mation _h be5 d[nfault$ into ! position 9 :i* he saw x 7,tracey & ,oriel #aiei2 ,e>dley #aiei74 ,! ,f[kes is actually ! y\nge/ ( ! ?ree =mations ( ,veat* & is consid]ably lat] 9 age ?an ! true ,wasat*4 ,! ,almy & ,knight =mations are n sep>able 7,oriel & ,tracey #aigj3af71 & c be se5 to grade into ea* o!r at ! bas9 edges4 ,illu/ration3 ,fig4 #e4 ,int]tongu+ relation%ip ( late/ ,cretace\s & ,t]ti>y /ratigraphic units ( ,fossil ,bas94 ,rec5t1 ,plei/oc5e ,plei/oc5e & ,rec5t gravel & alluvium ,plioc5e ,gooseb]ry ,memb] ( ,f[kes ,=mation ,oligoc5e to ,plioc5e ,hiatus ,eoc5e ,bridg]ian ,f[kes ,fm4 ,bulldog ,holl[ ,memb] ,sillem ,memb] ,uncon=mity ,wasat*ian3 ,wasat* ,=mation1 ,tunp ,memb] ,bullp5 ,memb] ,gre5 ,riv] ,=mation ,angelo ,memb] ,mud/one ,tongue ,fossil ,butte ,memb] ,s&/one ,tongue ,ma9 ,body ,l[] ,memb] ,basal ,conglom]ate ,memb] ,paleoc5e ,possible hiatus or uncon=mity ,evan/on ,=mation ,ma9 ,body ,hams ,=k ,conglom]ate ,memb] ,late/ ,cretace\s ,l[] ,memb] ,,uncon=mity ,late ,cretace\s ,adaville & old] =mations ,illu/ration3 ,fig4 #f4 ,subdivisions ( ,paleoc5e & ,eoc5e "t4 ,eoc5e ,late ,eoc5e ,u9tan ,mid ,eoc5e ,bridg]ian ,e>ly ,eoc5e ,wasat*ian ,lo/cab9ian ,lysitean ,graybullian ,paleoc5e ,late ,paleoc5e ,tiffanian ,mid ,paleoc5e ,torrejonian ,e>ly ,paleoc5e ,dragonian ,pu]can ,! ,almy & ,knight1 z def9$ by ,veat*1 are probably diff]5t facies ( ,wasat*1 ! ,almy be+ a m p]iph]al facies & ! ,knight a m bas9al facies 7,oriel & ,tracey #aigj74 ,^! au?ors propos$ t ! t]ms ,almy & ,knight be dropp$ & t ! "n ,wasat* be appli$ to all ^! rocks to avoid confusion4 ,! late/ subdivision ( ! ,wasat* ,=mation 9 ! ,fossil ,bas9 is t ( ,oriel & ,tracey4 ,! memb]s ( ! ,wasat* ,=mation !y propose are describ$ 9 ord] f olde/ to y\nge/4 ,,basal ,,conglom]ate ,,memb]4 ,?is memb] has only local developm5t 9 ,fossil ,bas94 ,:]e f\nd1 x is a l5ticul> conglom]ate ) pebbles & cobbles ( buff & tan s&/one f ! ,nugget ,s&/one & lime/one fragm5ts f ! ,?aynes & ,tw9 ,creek =mations4 ,! basal conglom]ate is ess5tially a *annel fill 9 anci5t /ream b$s cut into ,mesozoic rocks4 ,,l[] ,,memb]4 ,?is is an irregul> sequ5ce ( flood-pla9 & /ream-*annel deposits4 ,x is expos$ along ! s\!rn "p ( ! ,tunp ,range & ext5ds into ! f> we/]n section ( ,fossil ,butte ,national ,monum5t j bel[ ,pr[ ,po9t4 ,mud/one is ! ma9 rock type4 ,x c be tan1 br[n1 p9k1 r$1 or gray 9 color4 ,black1 c>bonace\s silt/ones are also pres5t4 ,gray s&/one t wea!rs yell[ or br[n & co>se-gra9$1 cross-b$d$ conglom]ate & s&/one are also prom95t4 ,lime/one occurs z ?9 l5ses & is (t5 br[n1 platy1 & c>bonace\s4 ,x is int]e/+ to note t ! ,l[] ,memb] is int]m$iate n only 9 /ratigraphic position b also 9 color & composition betwe5 ! und]ly+ ,evan/on ,=mation & ov]ly+ ,ma9 ,body ( ! ,wasat* ,=mation4 ,! ,l[] ,memb] ?us appe>s to repres5t a gradual *ange 9 ei!r climatic &_/or s$im5t>y conditions 9 ,fossil ,bas9 7,oriel & ,tracey #aigj74 ,illu/ration3 ,fig4 #g4 ,geologic map ( ,fossil ,butte ,national ,monum5t 7aft] ,rubey et al4 #aifh74 ,,leg5d ,quat]n>y--,qg-,qaf--,gravel /ream deposits ,eoc5e ,gre5 ,riv] ,fm4 ,tga--,angelo ,memb] ,tgf--,fossil ,butte ,memb] ,wasat* ,fm4 ,twb--,bullp5 ,memb] ,twm--,mud/one ,tongue ,tw--,ma9 ,body ,twl--,l[] ,memb] ,triassic ,,tr--,?aynes ,lime/one ,illu/ration3 ,fig4 #h4 ,,nw-,,se section across ,fossil ,butte ,national ,monum5t1 ,sage & ,kemm]] quadrangles 7mapp$ by ,rubey et al4 #aifh74 ,eoc5e ,twb--,bullp5 ,memb] ( ,wasat* ,fm4 ,tga--,angelo ,memb] ( ,gre5 ,riv] ,fm4 ,twm--,mud/one tongue ( ,wasat* ,fm4 ,tgf--,fossil ,butte ,memb] ( ,gre5 ,riv] ,fm4 ,tw--,ma9 body ( ,wasat* ,fm4 ,,ma9 ,,body4 ,?is unit ( ! ,wasat* ,=mation is t "p ( ! =mation :i* produces ! spectacul> r$-color$ badl&s 9 ,fossil ,butte ,national ,monum5t4 ,p>ticul>ly typical exposures c be se5 9 ! s\?-fac+ sc>p ( ,fossil ,butte :]e ! ,ma9 ,body makes up ! l[] portion ( ! butte4 ,! mo/ rem>kable feature ( ! ,ma9 ,body is its color4 ,on ! l[] slopes ( ,fossil ,butte are b&s ( bright to dull r$1 p9k1 purple1 yell[1 & gray color arrang$ 9 v>i\s patt]ns4 ,?is unit is be/ obs]v$ at a di/ance1 especially aft] a ra94 ,! bright hues ( ! ,wasat* contra/ m>k$ly ) ! :ites & tans ( ! ov]ly+ ,gre5 ,riv] ,=mation4 ,individual b&s ( color range f #a to #aj ft ?ick 7,oriel & ,tracey #aigj3gh74 ,! colors are brighte/ 9 ! upp] "p ( ! memb] & drabb] 9 ! co>s]-gra9$ l[] "p4 ,! pr$om9ant rock types 9 ! ,ma9 ,body are b&$1 v>iegat$ mud/one ) int]lay]$ s&/one1 conglom]ate1 m>l/one1 silt/one1 & clay/one4 ,! upp] "p ( ! ,ma9 ,body is ma9ly mud/one compos$ ( f9e silt & v f9e1 b$d$ s& ) a clay b9d]4 ,conglom]ates occur z *annel fills & conta9 calcium c>bonate z cem5t z d a numb] ( s&/one & silt/one lay]s 9 ! upp] ,ma9 ,body4 ,conglom]ates & s&/one are m common 9 ! l[] "p ( ! ,ma9 ,body4 ,"s are "p ( ,veat*'s old ,almy ,=mation4 ,!y are be/ develop$ along ! edge ( ,fossil ,bas94 ,! ,ma9 ,body ov]laps ! ,evan/on ,=mation 9 "s places & may re/ directly on ,mesozoic or ,paleozoic rocks4 ,,s&/one ,,tongue4 ,?is is a tongue ( cross-b$d$ s&/one4 ,x is br[n 9 color & is compos$ mo/ly ( qu>tz ) "s black *]t gra9s4 ,?is unit is limit$ 9 di/ribution to ! s\? ( ,fossil ,butte ,national ,monum5t4 ,! ,s&/one ,tongue ?9s & p9*es out to ! nor? & is n pres5t )9 ! monum5t4 ,! area ( p9*\t repres5ts ! %orel9e at "o /age ( ,fossil ,lake4 ,! ,s&/one ,tongue w$ges into ! ,fossil ,butte ,memb] ( ! ,gre5 ,riv] ,=mation4 ,! s$im5t s\rces 7 probably ! ,u9ta ,m\nta9s at ! s\? edge ( ,fossil ,bas94 ,tectonic ev5ts caus$ an uplift & erosion ( ,mesozoic & ,paleozoic rocks 9 ! ,u9tas & debris 0 deposit$ 9 ,fossil ,lake z an encroa*+ delta ( s&4 ,:5 deposition ( ! s& halt$1 ! lake exp&$ & cov]$ ! s&1 encas+ x )9 ! %ales ( ! ,gre5 ,riv] ,=mation4 ,! ,s&/one ,tongue c be trac$ into ! ,ma9 ,body ( ! ,wasat*1 h5ce its assignm5t to ! ,wasat* ,=mation4 ,,mud/one ,,tongue4 ,?is tongue ( ! ,wasat* ,=mation c be se5 9 ! nor?we/]n "p ( ,fossil ,butte ,national ,monum5t & ov] mo/ ( ! nor!rn "p ( ,fossil ,bas94 ,9 ! area ( its di/ribution1 ! ,mud/one ,tongue sep>ates ! und]ly+ ,fossil ,butte ,memb] ( ! ,gre5 ,riv] ,=mation f ! ov]ly+ ,angelo ,memb] ( ! ,gre5 ,riv] ,=mation4 ,! tongue ?9s & disappe>s to ! s\?1 t is1 bas9w>d4 ,z ) ! ,s&/one ,tongue1 ! edges ( ! ,mud/one ,tongue :]e x p9*es out repres5t an anci5t %orel9e ( ,fossil ,lake4 ,to ! nor? & we/ ! ,mud/one ,tongue m]ges ) ! ,tunp ,memb] ( ! ,wasat* ,=mation4 ,! ,mud/one ,tongue is a composite ( d>k-r$ mud/one :i* becomes light] 9 color bas9w>d1 *ang+ to light r$1 p9k1 or gre5i%-gray clay/one4 ,! unit is a mixture ( silt & clay d]iv$ f ! nor? & we/1 & 0 deposit$ z a l>ge delta 9 ,fossil ,lake4 ,an int]e/+ aspect ( ! ,mud/one ,tongue is ! pres5ce ( algal logs4 ,^! are cyl9d]s ( lime/one t app>5tly =m$ z an encru/ation ( calcium c>bonate ar\nd logs & bran*es t fell into ! edge ( ! lake4 ,! calcium c>bonate result$ f ! action ( algae :i* grew ar\nd ! log4 ,successive gr[?s ( algae result$ 9 successive lay]s ( calcium c>bonate be+ deposit$4 ,,bullp5 ,,memb]4 ,?is upp]mo/ memb] ( ! ,wasat* ,=mation is f\nd mo/ly to ! we/ & s\? ( ! monum5t4 ,a few1 small1 isolat$ caps on ! top ( ! ,gre5 ,riv] ,=mation ea/ ( ,pr[ ,po9t occur )9 ! monum5t4 ,^! l[ hills1 m]e bumps1 are remnants ( a once m ext5sive di/ribution ( ! ,bullp5 ,memb]4 ,veat* 7#aijg3ii7 orig9ally consid]$ :at is n[ call$ ! ,bullp5 ,memb] z be+ ! ,bridg] ,=mation1 ?is 0 bas$ mo/ly on ! ,bullp5's position above ! ,gre5 ,riv] ,=mation r ?an on any li?ologic resemblance to ! ,bridg]4 ,! ,bullp5 is mu* r$d] 9 color ?an ! ,bridg]4 ,9 e>ly "w ,tracey & ,oriel 7#aiei3gbi7 call$ ^! b$s an upp] tongue ( ! ,wasat* & h s9ce nam$ !m ! ,bullp5 ,memb]4 ,! ,bullp5 ,memb] is li?ologically v l ! ,ma9 ,body ( ! ,wasat* & c be trac$ into ! p]iph]al units ( ! ,wasat* ,=mation4 ,! rocks includ$ )9 ! ,bullp5 ,memb] are lay]$ sequ5ces ( r$1 p9k1 gray1 & gre5 clay/one & mud/one4 ,b5tonite is pres5t 9 "s clay/one b$s & causes sl\gh+ because ( its prop]ty ( exp&+ :5 wet4 ,"s s&/ones are pres5t 9 ! nor!rn areas ( ! memb]'s di/ribution4 ,lime/ones are also pres5t4 ,!y are ?9 & slabby & h a br[n1 :ite1 or gray color4 ,"s conta9 v>y+ am\nts ( clay4 ,a conglom]ate is pres5t 9 ! upp] "p ( ! ,bullp5 t[>d ! bas9 p]iph]y & m]ges ) ! ,tunp ,memb] ( ! ,wasat* ,=mation4 ,! ,bullp5 ,memb] is con=mable ) ! und]ly+ ,angelo ,memb] ( ! ,gre5 ,riv] ,=mation4 ,! contact is a transitional "o reflect+ a gradual *ange f ! lake environm5t ( ! ,gre5 ,riv] ,=mation ?r\gh a swamp environm5t to t ( a flood pla94 ,! light-color$1 f9e-gra9$ %ales1 m>l/ones1 & lime/ones ( ! ,gre5 ,riv] ,=mation grade upw>d into drabb]1 co>s] gra9$ clay & mud/ones ( ! ,bullp5 ,memb] z a reflection ( ?is *ange ( environm5ts4 ,,tunp ,,memb]4 ,?is p]iph]al unit ( ! ,wasat* ,=mation 0 fir/ describ$ by ,oriel & ,tracey 9 #aigj4 ,x is n expos$ 9 ! monum5t1 b =ms a belt ( outcrops ar\nd ! edge ( ,fossil ,bas9 & 9 *annels cut at "r angles to ! bas9 edge4 ,! ,tunp ,memb] is se5 to int]tongue ) ne>ly all ( ! ,wasat* & ,gre5 ,riv] =mations4 ,! memb] grades lat]ally bas9w>d f co>se1 angul> conglom]ates to f9e mud/one4 ,two lime/one tongues ( ! ,gre5 ,riv] ,=mation are int]b$d$ ) ! ,tunp1 indicat+ t at lea/ twice !re 0 major expansion ( ! lake4 ,li?ologically1 ! ,tunp ,memb] is a diamictite4 ,?is is a s$im5t>y rock ) a wide range ( p>ticle sizes4 ,! ,tunp is be/ describ$ z a r$1 conglom]atic1 s&y mud/one ) angul>1 poorly r\nd$ to smoo?1 well-r\nd$ cla/s ) a size range f pebble to b\ld]4 ,!re is no b$d+ or ori5tation ( cla/s4 ,! ,tunp ,memb] probably orig9at$ f mudfl[s & gravity slid+ 7,tracey et al4 #aifa74 ,environm5tal /udies indicate t ! area _h a w>m1 humid climate4 ,?is w\ld cause deep wea!r+ ( ! surr\nd+ slopes4 ,?is wea!r$ mat]ial w\ld !n be a prime s\rce to be act$ ^u by ra91 gravity1 & possibly e>?quakes4 ,^! ag5ts ( deposition w\ld !n cause ! mat]ial to fl[ & be deposit$ ) little *ance = sort+ & r\nd+ ( ! rock p>ticles4 ,! result 0 a belt ( co>se1 unsort$ detritus on ! bas9 edges n[ call$ ! ,tunp ,memb]4 ,,age ,,( ,,! ,,wasat* ,,=mation4 ,! exact age ( ! units )9 ! ,wasat* ,=mation c be det]m9$ only if fossils are pres5t4 ,none has be5 f\nd 9 ! basal conglom]ates b x is believ$ to be e>lie/ ,eoc5e4 ,! ,l[] ,memb] is also n dat$ ) fossils b is believ$ to be v e>ly ,eoc5e4 ,a numb] ( fossil mammals are kn[n f ! ,ma9 ,body ( ! ,wasat* ,=mation4 ,! l[] "p is e>ly1 e>ly ,eoc5e z demon/rat$ by ! pres5ce ( a v primitive ungulate1 ,haplomylus speirianus4 ,9 ! upp] "p ( ! ,ma9 ,body ano!r primitive ungulate1 ,hyopsodus br[ni1 is f\nd :i* indicates a mid to e>ly ,eoc5e age4 ,! ,mud/one & ,s&/one tongues are n dat$ by means ( fossils b ! /ratigraphic relation%ips indicate an e>ly ,eoc5e age4 ,fossil mollusks 9 ! ,bullp5 ,memb] are n completely diagno/ic b sugge/ ei!r a late e>ly ,eoc5e 7,lo/cab9ian7 7,fig4 #f7 or mid-,eoc5e age4 ,! ,tunp ,memb] int]f+]+ z x does ) ! entire ,wasat* section repres5ts all ( e>ly ,eoc5e age4 ,,depositional ,,environm5t4 ,! s$im5ts t make up ! ,wasat* ,=mation 9 ! ,fossil ,bas9 7 deposit$ ma9ly by /reams fl[+ into ! bas9 f ! surr\nd+ upl&s4 ,rock types are v>iable & = ! mo/ "p individual types _c be trac$ ov] l>ge areas1 a condition typical ( fluvial environm5ts4 ,! mud/ones & silt/ones probably 7 deposit$ along flood pla9s1 :ile ! l5ticul> s&s & conglom]ates 7 laid d[n 9 /ream *annels4 ,:]e /reams ent]$ ! lake tongues ( deltaic deposits1 s&s or mud/ones w$ge into ! ,gre5 ,riv] ,lake s$im5ts4 ,! reason = ! r$ color ( ! ,wasat* ,=mation is n fully kn[n4 ,accord+ to ,van ,h\t5 7#aidh71 ! r$ is mo/ likely ! result ( tropical1 r$ lat]itic soils =m+ 9 ! upl&s & be+ deposit$ on flood pla9s4 ,! oxidation ( organic mat]ial 9 a humid1 subtropical environm5t causes ! r$ color4 ,! b&s ( purple1 gray1 orange1 & o!r colors are due to v>i\s /ages 9 ! r$uction ( ! iron oxides 9 ! rocks4 ,! pres5ce ( palms 9 ! lake s$im5ts & ( bones ( primates & crocodiles 9 bo? ! lacu/r9e & fluvial s$im5ts indicate a heavily =e/$1 tropical environm5t4 ,gre5 ,riv] ,=mation ,! ,gre5 ,riv] ,=mation is easily recogniz$ by its light color & cont9u\s b$d+1 9 /rong contra/ to ! r$1 discont9u\s1 v>iegat$ ,wasat* ,=mation bel[4 ,! ,gre5 ,riv] ,=mation c be ?\ght ( z a gigantic l5s ( lacu/r9e s$im5ts enclos$ 9 ! fluvial ,wasat* ,=mation4 ,! "n ,gre5 ,riv] ,=mation is appli$ to all ( ! r\ghly contemporane\s deposits laid d[n 9 lakes ( ,utah1 ,colorado1 & ,wyom+4 ,x is probable t at "o "t or ano!r all ( ^! lakes 7 connect$4 ,oriel & ,tracey 7#aigj7 h divid$ ! ,gre5 ,riv] ,=mation ( ! ,fossil ,bas9 into two memb]s3 ! ,fossil ,butte ,memb] & ! ,angelo ,memb]4 ,,fossil ,,butte ,,memb]4 ,! type section = ?is memb] is ne> ! s\!a/]n end ( ,fossil ,butte )9 ! monum5t b\nd>ies4 ,9 ! type area ! ,fossil ,butte ,memb] c be se5 to consi/ ( f\r li?ologic units4 ,! l[]mo/ unit is pr$om9antly mud/one4 ,x occurs 9 a sequ5ce ab\t #de ft ?ick & conta9s light gray1 f9e-gra9$1 calc>e\s mud/one & silt/one4 ,! next ov]ly+ unit is ab\t #ge ft ?ick & is ma9ly a lime/one unit4 ,x consi/s ( tan to gray lime/one1 %aly lime/one1 silt/one1 & pap] %ale :i* wea!rs into ?91 curl$ flakes4 ,a yell[-br[n mud/one tops ?is unit4 ,! ?ird unit 9 ! sequ5ce is #de ft ?ick & ma9ly compos$ ( %ales4 ,^! %ales wea!r a buff color & are calc>e\s4 ,oil %ale1 organic ri* pap] %ale1 & m>l/one comprise ! actual lay]s 9 ! unit4 ,a few1 ?9 a% b$s are also pres5t4 ,?is unit is ! mo/ significant "o = ,fossil ,butte ,national ,monum5t4 ,ab\t #aj ft bel[ ! top ( ?is unit 7ab\t #aee ft above ! ,wasat*7 is a b$ ( v>v$ %ales1 "o foot ?ick1 t conta9s ! fossil fi% = :i* ! monum5t 0 e/abli%$4 ,! upp]mo/ unit conta9s a numb] ( b$s ( oil %ale t are br[n on a fre% surface b wea!r a grayi%-:ite4 ,an orange-yell[-wea!r+ lime/one caps ! #dj-;ft ?ick upp] unit4 ,a% b$s are common & traceable ov] a wide area ( ,fossil ,bas94 ,s\? ( ! monum5t ! ,s&/one ,tongue ( ! ,wasat* ,=mation w$ges 9 betwe5 ! l[]mo/ unit & ! ov]ly+ lime/one unit ( ! ,fossil ,butte ,memb]4 ,9 ! ,fossil ,butte ,memb] an int]e/+ sequ5ce ( facies *anges c be se5 :i* reflect lat]al *anges 9 ! environm5t ( ,fossil ,lake4 ,9 ^? areas :]e ! memb] repres5ts a deep-wat] environm5t1 organically =m$ lime/ones & %ales are pr$om9ant4 ,%orew>d1 ^! rocks grade into o/racodal lime/one1 ga/rapodal lime/one1 &1 close/ to %ore1 algal lime/one4 ,!n a muddy1 s&y bea* facies is enc\nt]$ :]e ! ,gre5 ,riv] & ,wasat* =mations int]grade4 ,! contact ) ! und]ly+ ,wasat* is con=mable & %>p4 ,x is (t5 m>k$ by a b5* or by slump blocks ( ,gre5 ,riv] ,=mation4 ,! ,fossil ,butte ,memb] may 9 "s cases ov]lap ! ,wasat* ,=mation & be deposit$ on ,paleozoic & ,mesozoic rocks4 ,?is is a reflection ( topographic relief dur+ ! ,eoc5e4 ,! ?ickness ( ! ,fossil ,butte ,memb]1 z report$ by ,oriel & ,tracey 7#aigj3cg71 is f #bjh to #bfi ft4 ,,angelo ,,memb]4 ,9 ! nor!rn "p ( ,fossil ,bas91 ! ,mud/one ,tongue ( ! ,wasat* ,=mation sep>ates ! ,angelo ,memb] ( ! ,gre5 ,riv] ,=mation f ! ,fossil ,butte ,memb]4 ,fur!r s\?1 ! two memb]s re/ directly on "o ano!r4 ,! s\!rn ext5t ( ! ,angelo ,memb] has n be5 det]m9$ z yet1 b ,oriel & ,tracey 7#aigj3cb7 believe x ext5ds up to1 & int]tongues )1 ,wasat* conglom]ates ne> ! ,u9ta ,m\nta9s4 ,t[>d o!r edges ( ,fossil ,bas91 ! ,angelo ,memb] ?9s & p9*es out into ! ,wasat* ,=mation4 ,! ,bullp5 ,memb] ( ! ,wasat* re/s on top ( ! ,angelo ,memb]4 ,! ,angelo ,memb] consi/s ( :ite to blue-:ite wea!r+ lime/one1 m>l/one1 & mud/one4 ,"s s&/one l5ses1 clay/one1 oil %ale1 & silice\s lime/one are pres5t z well4 ,9 g5]al1 ,oriel & ,tracey 7#aigj7 h f\nd t buff lime/ones prevail to ! nor? & :ite1 silice\s lime/one1 to ! s\?4 ,l ! ,fossil ,butte ,memb]1 ! ,angelo ,memb] %[s a facies *ange f deep-wat] to %ore4 ,?is memb] =ms ! v upp]mo/1 r\nd$ slopes ( ,fossil ,butte 9 contra/ to ! m v]tical cliffs =m$ by ! ,fossil ,butte ,memb]4 ,,age ,,( ,,! ,,gre5 ,,riv] ,,=mation4 ,! age ( ! ,gre5 ,riv] ,=mation is dat$ on its int]tongu+ relation%ips ) ! ,wasat* ,=mation because ! latt] has datable mammal fossils4 ,! well-pres]v$ fossils ( fi%1 leaves1 & insects f ! ,gre5 ,riv] are1 un=tunately1 ( little value 9 dat+ ! ,gre5 ,riv] ,=mation4 ,al?\gh no ,lo/cab9ian mammals are kn[n f ,fossil ,bas91 ! ,gre5 ,riv] ,=mation is believ$ to be ( t age 7,gaz9 #aiei2 ,s*aeff] & ,mangus #aife74 ,,depositional ,,environm5t4 ,! ,gre5 ,riv] ,=mation1 on ! basis ( its li?ology & fossil cont5t1 is a fre%-wat]1 lacu/r9e deposit4 ,clay & silt 7 dump$ 9 ,fossil ,lake by /reams4 ,mo/ ( ?is f9e debris 0 deposit$ ne> ! %ore4 ,*emical & organic processes =m$ lime/ones & m>l/ones 9 ! deep] c5tral "p ( ! lake4 ,exam9ation ( ! edge ( ! ,gre5 ,riv] ,=mation indicates t ,fossil ,lake exp&$ & contract$ sev]al times4 ,fossil ,lake 0 ev5tually fill$ 9 ) *emical precipitates & deltaic deposits4 ,! end ( ! lake 0 gradual z se5 9 ! transitional & gradational ,gre5 ,riv]-,bullp5 contact4 ,al?\gh oil %ale is n ext5sively develop$ 9 ! ,gre5 ,riv] ,=mation ( ,fossil ,bas91 x does occur 9 small quantities4 ,oil %ale is a f9e-gra9$ s$im5t>y rock conta9+ organic matt] :i* 0 d]iv$ *iefly f aquatic organisms1 waxy spores & poll5 gra9s 444 & ( :i* a l>ge portion is di/illable into a liquid simil> to petroleum4 ,despite ! "n1 mo/ ri* b$s ( oil %ale 9 ! ,gre5 ,riv] ,=mation _c be reg>d$ /rictly z %ale4 ,in/ead1 !y are dolomitic m>l/ones ri* 9 organic matt]4 ,nev]!less1 a few are %aly 7,bradley #aifd;b3#ai74 ,oil %ale has a /ructureless gr\nd mass t is yell[i%-orange to r$di%-orange 9 color4 ,pyrite cry/als are f\nd indicat+ a p>tially ana]obic or r$uc+ environm5t4 ,poll51 waxy spores1 filam5ts ( algae1 & o!r plant p>ts are pres]v$ along ) insects & l>vae4 ,! pres]vation is ak9 to mummification4 ,cry/als ( calcite1 dolomite1 or au?ig5ic feldsp> are also f\nd 9 ! oil %ale 7,bradley #aiff74 ,! exact mode ( orig9 ( oil %ale is n positively kn[n because ( a lack ( a mod]n analogue = comp>ison4 ,oil %ale probably orig9at$ z an organic ooze on ! bottom ( ! ,fossil ,lake4 ,?is ooze 0 compos$ ( ! rema9s ( phytoplankton1 blue-gre5 algae1 zooplankton1 bact]ia1 & "s poll5 & spores4 ,! ooze 0 d5se & uncompact$4 ,little cla/ic debris is f\nd1 ei!r because ! ooze accumulat$ 9 deep wat] or plants ne> ! %ore filt]$ out ! debris4 ,decay 0 r$uc$ effectively 9 ! ooze because ( ei!r an antibiotic 9 ! ooze :i* inhibit$ bact]ia ( decay or ! ooze accumulat$ 9 wat]s :]e ana]obic conditions prev5t$ decay4 ,) "t & ! weight ( ov]ly+ s$im5ts1 ! ooze 0 compact$ & mo/ ( its wat] driv5 (f4 ,cont9u+ pressure f compaction & heat g5]at$ by burial & compaction caus$ a v>iety ( complex *emical reactions :i* conv]t$ ! ooze into a petroleum product call$ k]og54 ,k]og5 is di/illable & is ! important con/itu5t ( oil %ale4 ,an alt]nate hypo!sis 7,eug/] & ,surdam #aigc71 w\ld h "s oil %ale =m+ 9 a des]t-playa environm5t4 ,?is is bas$ on geo*emical evid5ce f\nd 9 ,gosiute ,lake s$im5ts to ! ea/ ( ,fossil ,lake4 ,!re1 c]ta9 m9]als are f\nd 9 association ) "s oil %ale t c\ld only h be5 deposit$ dur+ p]iods ( extreme evaporation & 9 a %all[ lake4 ,mu* /udy is n[ be+ direct$ t[>d a solution to ^! problems4 ,! combu/ible quality ( oil %ale has be5 kn[n = a long "t4 ,_m ( ! pione]s us$ x z a fuel = cook+ & heat4 ,hayd5 7#ahga3adb7 wrote ( h[ workm5 on ! ,union ,pacific accid5tly ignit$ ! oil %ale 9 a cut !y 7 excavat+4 ,! burn+ %ale provid$ en\gh light = night "w4 ,_m ( ! %ales ( ! ,gre5 ,riv] ,=mation appe> to be v>v$4 ,a v>ve consi/s ( two lay]s1 "o ( calcium or magnesium c>bonate & "o ( organic mat]ial4 ,! limnological conditions t l$ to ! =mation ( v>ves w be discuss$ 9 _! prop] place 9 ! section on ,paleoecology4 ,f[kes ,=mation ,?is is ! middle =mation ( ,veat*'s 7#aijg7 trip>tite division ( ! ,wasat* ,gr\p4 ,x is n[ f\nd to be ! y\nge/ =mation 9 ,fossil ,bas94 ,x is n expos$ 9 ,fossil ,butte ,national ,monum5t4 ,oriel & ,tracey 7#aigj7 h =mally divid$ & nam$ ?ree memb]s ( ! ,f[kes ,=mation3 a l[] ,sillem ,memb]1 a middle ,bulldog ,holl[ ,memb]1 & an upp] ,gooseb]ry ,memb]4 ,,sillem ,,memb]4 ,l mo/ ( ! ,f[kes ,=mation1 ?is sequ5ce ( rocks has be5 erod$ ext5sively & is pres]v$ z erosional remnants1 :]e protect$ by fault+1 9 ! we/]n "p ( ,fossil ,bas94 ,! ,sillem ,memb] consi/s ( a l[] conglom]atic sequ5ce ) "s s&/one & mud/one4 ,! conglom]ate conta9s well-r\nd$ cla/s ( gray qu>tzite1 *]t1 & ,paleozoic lime/one4 ,! s&/one is light gray1 calc>e\s to muddy1 & co>se to m$ium-gra9$4 ,! mud/one is p9k1 gray1 or tan 9 color4 ,! upp] "p ( ! ,sillem ,memb] is a mud/one & clay/one unit4 ,x ranges 9 color f p9k & yell[ to gray & gre54 ,"s volcanic debris is f\nd4 ,!re are also int]b$d$ lay]s ( m>l/one & lime/one4 ,"s s&/one is pres5t4 ,! ,sillem ,memb] is betwe5 #ajj & #djj ft ?ick & mo/ probably re/s uncon=mably on ! ,bullp5 ,memb] ( ! ,wasat*4 ,,bulldog ,,holl[ ,,memb]4 ,?is middle memb] ( ! ,f[kes ,=mation has ! ?icke/ & mo/ ext5sive outcrops4 ,! ,bulldog ,holl[ ,memb] is expos$ along ! we/ side ( ! bas94 ,includ$ rocks are gre51 :ite1 & blue-gre5 mud/one ) a% b$s1 gre5 & buff clay/one1 & tufface\s1 limy s&/one4 ,a high p]c5tage ( ! iron m9]al1 magnetite1 occurs 9 ! s&/one4 ,conglom]ate occurs z l5ses4 ,! ,bulldog ,holl[ ,memb] has a gradational contact ) ! und]ly+ ,sillem ,memb]4 ,! am\nt ( volcanic mat]ial increases upw>d f ! ,sillem1 indicat+ an increase 9 volcanic activity dur+ ! deposition ( ! ,bulldog ,holl[ ,memb]4 ,,gooseb]ry ,,memb]4 ,oriel & ,tracey 7#aigj3ee7 place ?is upp]mo/ memb] provisionally )9 ! ,f[kes ,=mation4 ,mo/ ( ! ,gooseb]ry ,memb] is a pudd+/one1 a li?ology ) well-r\nd$1 sph]ical pebbles 9 a m>l/one1 s&/one1 or s&y lime/one matrix4 ,! pebbles are too r\nd$ = ! rock to be a diamictite1 & too sep>at$ f ea* o!r to be call$ a conglom]ate4 ,! nature ( ! ,gooseb]ry-,bulldog ,holl[ contact is n completely kn[n4 ,x appe>s to be gradational 9 "s areas & to be an angul> uncon=mity 9 o!rs4 ,,age ,,( ,,f[kes ,,=mation4 ,fossils date ! ,sillem & ,bulldog ,holl[ memb]s z middle ,eoc5e 9 age4 ,^! fossils consi/ ( o/racodes1 ga/ropods1 leaves1 & v]tebrates f ! ,bulldog ,holl[ ,memb] 7,nelson #aigc74 ,! ,gooseb]ry ,memb] has yield$ a few v]tebrate rema9s & is late ,mioc5e or e>ly ,plioc5e 9 age 7,oriel & ,tracey #aigj74 ,,depositional ,,environm5t4 ,! ,f[kes ,=mation is an alluvial deposit1 mu* l ! ,wasat* ,=mation4 ,! *emical & climatic conditions ( deposition 7 diff]5t f ^? ( ! ,wasat*1 & ! ext5sive r$-b$s are n develop$4 ,small lakes 7 pres5t 9 :i* lime/one & m>l/one accumulat$4 ,! pudd+/one may be a mudfl[4 ,volcanic activity left its record 9 ! a% f\nd 9 ! ,f[kes ,=mation4 ,9 ! pa/1 ! ,f[kes ,=mation _h a great] di/ribution4 ,po/depositional fault+ d[n dropp$ p>ts ( ! ,f[kes protect+ !m f subsequ5t erosion4 ,,quat]n>y ,rubey et al4 7#aifh;a1 b7 h mapp$ sev]al =ms ( ,quat]n>y deposits 9 ,fossil ,bas94 ,^! include /ream alluvium1 rock & l&slide debris1 riv] t]races1 & gravels1 all d]iv$ f local =mations4 ,^! deposits are ! "w ( wat]1 w9d1 & ice act+ 9 relatively ,rec5t "t4 ,,! ,,geologic ,,/ructure ,,( ,,fossil ,,bas9 ,! ,fossil ,bas9 is a small1 l9e> & /ructurally controll$ bas9 9 ! s\!a/]n "p ( ! ,wyom+ ov]?ru/ belt4 ,?is 8ov]?ru/ belt0 is repres5t$ by a numb] ( small m\nta9 ranges & high ridges =m$ by ! 8?ru/+0 ( s$im5t>y rocks ov] o!r s$im5t>y rocks4 ,topographically1 ! ,fossil ,bas9 is b\nd$ by ! ,craw=d ,m\nta9s & ,tunp ,range on ! we/1 by ,oy/] ,ridge on ! ea/1 & by ! ,u9ta ,m\nta9s on ! s\?4 ,! ,craw=d ,m\nta9s1 ,tunp ,range1 & ,oy/] ,ridge 7,fig4 #b7 are areas ( high relief develop$ ^u s\!rly ext5d$ sali5t ridges ( de=m$ ,paleozoic & ,mesozoic /rata4 ,9 ! c5t] ( ! ,fossil ,bas91 ^! e>li] rocks are cov]$ by a v5e] ( e>ly ,t]ti>y s$im5ts4 ,sup]ficially1 ! ,fossil ,bas9 appe>s to be a broad syncl9e ) tilt$ b$s dipp+ %>ply or g5tly bas9w>d f ! bas9 m>g9s4 ,! ,t]ti>y s$im5t>y cov]1 h[ev]1 p>tially obscures :at is a m complex /ructural hi/ory4 ,foll[+ deposition ( ! ,late ,cretace\s ,adaville ,=mation1 ! ,fossil ,bas9 0 includ$ 9 a p]iod ( int5se /ructural de=mation4 ,?is de=mation 0 ! result ( compressional =ces act+ along a m or less ea/-we/ alignm5t4 ,! /ra91 or ! resolution ( ^! =ces1 0 develop$ along a nor?-s\? alignm5t or p]p5dicul> to ! compressional =ces4 ,z ! /ress level became too great1 ! rocks 7 fir/ fold$ & !n fault$4 ,initial fault+ ( ! rocks reliev$ "s ( ! /ress2 h[ev]1 ) cont9u$ application ( compressive =ces _m /ages ( fold+ & fault+ 7 g5]at$4 ,because ! alignm5t ( ! compressive =ces rema9$ ab\t ! same ?r\gh\t de=mation 7i4e41 ea/-we/7 & because ! /ronge/ relative compressive =ces 7 f ! we/1 successively y\ng] folds & faults 7 g5]at$ 9 an ea/w>d direction4 ,! /ructural evolution ( ! ,fossil ,butte area may be int]pret$ z foll[s f ! s*ematic diagrams3 #a4 ,! ,rock ,creek-,ne$les ,anticl9e is develop$ at ! we/]n edge ( ! ,fossil ,bas94 ,! pres5t topographic highs develop$ on ?is /ructure are ! ,craw=d ,m\nta9s & ,tunp ,range 7,fig4 #i-;,b74 #b4 ,) cont9u$ application ( compressional =ces1 ,paleozoic & ,mesozoic rocks to ! ea/ ( ! ,rock ,creek-,ne$les ,anticl9e are fold$ 7,fig4 #i-;,c74 #c4 ,! fold becomes %>ply asymmetrical & :5 ! rocks c no long] accommodate ! compressional =ces by fur!r fold+1 a l[-angle fault is develop$ 7,abs>oka ?ru/ fault74 ,?is fault probably began z a fracture p>allel to b$d+ :i* rose to topographic surface at a l[ angle at ! po9t ( greate/ /ra9 9 ! fold4 ,mo/ likely1 ?is fracture 0 an ea/w>d ext5sion ( ! fault und]ly+ ! ,rock ,creek-,ne$les ,anticl9e1 z depict$ 9 ,fig4 #i-;,d4 #d4 ,! rocks to ! we/ ( ! newly develop$ fault ov]rode ^? to ! ea/4 ,?is 0 accompani$ by fur!r d[nw>p+ 9 ! syncl9e to ! ea/ ( ! fault & ! erosion ( uplift$ s$im5t>y rocks on ! we/ side ( ! fault 7,fig4 #i-;,e74 #e4 ,ano!r cycle ( fold+ & fault+ 0 initiat$ to ! ea/ ( ! ,abs>oka fault4 ,?is po/-,abs>oka de=mation in/igat$ fur!r d[nw>p+ ( ! ,fossil ,bas9 area betwe5 ! ,tunp-,craw=d ,m\nta9s & ,oy/] ,ridge4 ,t]ti>y s$im5ts began to accumulate 9 ! ,fossil ,bas9 7,fig4 #i-;,f74 ,illu/ration3 ,fig4 #i4 ,/ructural developm5t ( ! ,fossil ,butte area4 ,,leg5d ,t--,t]ti>y ,k1 ,k--,cretace\s ,j--,jurassic ,,tr--,triassic ,pz--,paleozoic ,x--,position ( ,fossil ,butte 1 --,relative movem5t along faults ,illu/ration3 ,a4 ,pre-de=mation3 ,paleozoic ,mesozoic ,=mations ,illu/ration3 ,b4 ,pre-,abs>oka ,de=mation ,illu/ration3 ,c4 ,developm5t ( ! ,abs>oka ?ru/ fault3 fold+ ,illu/ration3 ,d4 ,developm5t ( ! ,abs>oka ?ru/ fault3 fault+ ,illu/ration3 ,e4 ,developm5t ( ! ,abs>oka ?ru/ fault3 fault+ ,illu/ration3 ,f4 ,po/-,abs>oka ,?ru/ ,de=mation ,illu/ration3 ,g4 ,simplifi$ /ructure section ?r\gh pres5t-day ,fossil ,bas9 7,oy/] ,ridge is (f ! diagram to ! ,ea/7 ,/ructural int]pretation by ,dr4 ,d4,l4 ,black/one ,9 e>ly ,eoc5e times1 ! effects ( cont9u$ d[nw>p+ all[$ ,fossil ,lake to =m 9 ! ,fossil ,bas94 ,by ! late ,eoc5e1 h[ev]1 bas9al subsid5ce c\ld no long] keep pace ) deposition & ! dom9antly lacu/r9e 7lake7 s$im5tation 0 replac$ by a fluviatile 7riv]9e7 s$im5t>y regime4 ,deposition ( fluviatile s$im5ts probably cont9u$ into ! lat] ,t]ti>y :51 9 ! late ,plioc5e1 regional uplift ( ! ,rocky ,m\nta9 int]ior rev]s$ ! s$im5t>y cycle f depositional to erosional4 ,! la/ #c or #d million ye>s ( geologic hi/ory h witness$ ! excavation ( mu* ( ! ,t]ti>y s$im5t>y fill f ! ,fossil ,bas94 ,fossil ,butte & ! ,ham's ,=k ,plateau to ! nor!a/ ( ! butte are high erosional remnants ( ?is e>ly ,t]ti>y bas9 fill4 ,! traces ( ! ,abs>oka & o!r ?ru/ faults are buri$ b5ea? ^! rema9+ ,t]ti>y deposits 9 ! ,fossil ,bas94 ,:ile mo/ ( ?is complex /ructural hi/ory took place be=e ! ,t]ti>y s$im5ts 7 deposit$1 "s de=mation cont9u$ into ! e>ly ,eoc5e4 ,ne> ,pr[ ,po9t1 = example1 is a fault t develop$ dur+ e>ly ,eoc5e "t4 ,?is c be not$ 9 ! v nor?we/ corn] ( ! monum5t1 j to ! we/ ( ,pr[ ,po9t 7,fig4 #f74 ,"h1 ! ,l[] ,memb] ( ! ,wasat* ,=mation on ! we/ is fault$ aga9/ ! ,ma9 ,body on ! ea/ 7,,usdi #aifd74 ,?is fault also is responsible = elevat+ ! ,?aynes ,lime/one s x is expos$ 7,fig4 #aj74 ,illu/ration3 ,fig4 #aj4 ,/ructural relation ( old] rocks to ,wasat* & ,gre5 ,riv] =mations ne> ,pr[ ,po9t 9 ! nor?we/ corn] ( ! monum5t 7f ,u4,s4 ,dep>tm5t ( ,int]ior #aifd74 ,,paleontology ,fossils ( plants1 inv]tebrates1 & v]tebrates are abundant 9 rocks expos$ 9 ! ,fossil ,bas94 ,= example1 ,oy/] ,ridge receiv$ its "n because ( ! well-pres]v$ & abundant fossil oy/]s f\nd !re4 ,( c\rse1 ,fossil ,butte & ,fossil ,butte ,national ,monum5t 7 s nam$ because ( ! beautifully pres]v$ fossil fi%4 ,a brief review ( ! ma9 gr\ps ( fossils to be f\nd 9 ! bas9 foll[s4 ,flora ,_m ( ! s$im5ts 9 ! ,fossil ,bas9 conta9 an abundance ( fossil plants4 ,^! consi/ ( poll51 spores1 wood1 & leaf impressions4 ,^? ( ! ,gre5 ,riv] ,=mation are be/ pres]v$ & h receiv$ ! mo/ /udy4 ,br[n 7#aibi1 #aicd7 & ,lesqu]eux 7#ahhc7 h pres5t$ ! be/ in=mation on ! flora ( ! ,gre5 ,riv] ,=mation4 ,mu* ( ! pres5t k is bas$ on _! "w4 ,br[n 7#aibi1 #aicd7 conclud$ t ! ,gre5 ,riv] flora is a mix$ =e/ type4 ,x conta9s "s plants common to w>m1 wet l[l&s & o!rs adapt$ to cool]1 dri] upl&s4 ,poll5 /udies support ,br[n's orig9al concept t sev]al plant communities1 includ+ m\nta9 communities1 exi/$ ar\nd ,fossil ,lake4 ,! flora 0 situat$ 9 an inl&1 m\nta9 bas94 ,fossil ,lake 0 9 ! middle ( ! bas94 ,swamps & flood pla9s bord]$ ! lake1 :ile ! flank+ ridges & m\nta9s provid$ altitud9al v>iations 9 ! plant assemblage4 ,spruce1 fir1 & p9e are indicat$ by fossil poll54 ,! pres5ce ( ^! conif]s sugge/ t at lea/ "s ( ! ne>by m\nta9s rose to heights ( #fjjj-hjjj ft4 ,leaf impr9ts indicate t decidu\s trees occurr$ on ! l[] slopes4 ,oak1 elm1 maple1 & bee* 7 common =ms4 ,clos] to ! lake :]e x 0 wett] & w>m] !re 7 will[s1 laurel1 & fig trees4 ,palms grew 9 ! s&i] soils 7,fig4 #aa74 ,cypress grew 9 quiet embaym5ts ( ,fossil ,lake4 ,! %orel9e plant assemblage _h a r subtropical appe>ance4 ,illu/ration3 ,fig4 #aa4 ,impression ( a palm frond f ! fi% b$s ( ,fossil ,bas94 ,wid? ( orig9al1 #afj mm4 ,collection ( ,univ]sity ( ,wyom+4 ,gr\nd cov] 0 provid$ by a mold ( dead leaves1 holly1 liv]worts1 mosses1 & f]ns 7,fig4 #ab74 ,prairie-type grasses are n pres5t & l>ge savanna areas probably 7 n develop$4 ,illu/ration3 ,fig4 #ab4 ,a f]n leaf f ! ,gre5 ,riv] ,%ales ( ! ,gre5 ,riv] ,bas94 ,wid? ( orig9al1 #d cm4 ,collection ( ,univ]sity ( ,wyom+4 ,9 ! lake itself small1 "o-cell$ algae float$ ab\t 9 ! waves & curr5ts4 ,bact]ia grew on ! lake bottom & 9 ! wat] & help$ to contribute to ! organic ooze t built up on ! bottom4 ,fungi1 wond]fully pres]v$ 9 oil %ales1 are fur!r indicators t ,fossil ,lake 0 a fre%-wat] lake & deep en\gh to h dep?s bel[ ! zone ( sunlight p5etration 7,bradley #aifd;a74 ,re$s1 ru%es1 & simil> lake-%ore plants grew 9 %all[1 ne>-%ore wat]s4 ,! l>ge am\nt ( organic mat]ial 9 ! rocks is evid5ce ( ! prolific microscopic plant gr[? 9 ! lake4 ,occasional dry p]iods 9 ! ,fossil ,bas9 are indicat$ by fossils ( a plant call$ ,eph$ra4 ,?is plant _h leaves ) a ?ick1 waxy cuticle to prev5t desiccation dur+ dr\ght4 ,! abs5ce ( sal9e m9]als 9 ! ,gre5 ,riv] ,=mation 9 ,fossil ,bas9 sugge/s t ^! arid p]iods 7 nev] ( ! int5sity t occurr$ 9 ! ,gre5 ,riv] ,bas9 to ! ea/4 ,! flora ( ,fossil ,bas91 especially t f ! ,gre5 ,riv] ,=mation1 is usually comp>$ to t ( ! pres5t-day ,gulf ,coa/4 ,seaw>d f ! ,appala*ians1 ! composition ( ! flora is v simil> to t ( ! ,gre5 ,riv]4 ,spruce1 p9e1 & fir gr[ 9 ! ,appala*ians at elevations ( #fjjj or m feet1 support+ ! idea t simil> elevations exi/$ ne> ,fossil ,lake & t a g5]al ,gulf ,coa/ climate prevail$ 9 ,fossil ,bas94 ,inv]tebrates ,molluscs1 o/racodes1 & insects comprise ! inv]tebrate fauna ( ,fossil ,bas94 ,a l>ge numb] ( m>9e =ms are f\nd 9 ! e>li] m>9e deposits1 :ile fre%-wat] & t]re/rial =ms are common 9 ! ,t]ti>y units4 ,x is ^! lat] =ms :i* are consid]$ "h4 ,! fre%-wat] & t]re/rial molluscs f ! ,wasat* & ,gre5 ,riv] =mations include bivalves 7clams7 & ga/ropods 7snails74 ,aquatic clams f ! ,gre5 ,riv] ,=mation include ,unio & ,plesiellipta4 ,pisidium & ,spha]ium are common 9 ! ,wasat* ,=mation4 ,l& snails f ! ,wasat* include su* g5]a z ,grang]ella1 ,discus1 ,oreoconus1 & ,glypt]pres4 ,oreoconus is also kn[n f ! ,gre5 ,riv] ,=mation4 ,fre%-wat] snails are v abundant f bo? ! ,wasat* & ,gre5 ,riv] =mations4 ,physa1 ,planorbis1 ,elimia1 ,bioniphal>ia1 ,virpa9s1 & ,omalodiscus are f ! ,wasat*4 ,physa1 ,elimia1 ,diomphal>ia1 & ,goniobasis are record$ f ! lacu/r9e ,gre5 ,riv] s$im5ts4 ,9 "s areas ( ! ,gre5 ,riv] ,=mation1 ^! snail fossils are s abundant t !y =m a major con/itu5t ( ! lime/ones4 ,! pres5ce ( l& snails 9 ! ,gre5 ,riv] & fre%-wat] molluscs 9 ! ,wasat* is evid5ce t ! two =mations are n totally repres5tative ( a s+le environm5t1 b repres5t sev]al relat$ ones4 ,mo/ ( ^! fre%-wat] snails 7 h]bivor\s & frequ5t$ ! %all[1 well-light$ areas ( ,fossil ,lake :i* _h a good gr[? ( plants & algae4 ,?is naturally occurr$ close to %ore1 h5ce ! ga/ropodal lime/ones report$ by ,bradley 7#aibf7 & ,oriel & ,tracey 7#aigj7 are int]pret$ z be+ ne>-%ore facies4 ,o/racodes are extremely small ar?ropods t produce a two-piece1 h+$ %ell )9 :i* !y live4 ,pseudocypus is ! mo/ common =m4 ,l ! snails1 ! o/racodes 7 s abundant 9 areas t !y1 too1 =m$ a l>ge "p ( "s ,gre5 ,riv] ,=mation lime/ones4 ,& l ! snails !y liv$ 9 a ne>-%ore environm5t4 ,)9 ! lam9at$ %ales ( ! ,gre5 ,riv] ,=mation is pres]v$ an abundant & div]se assemblage ( fossil insects 7,fig4 #ac74 ,^! insects are important because !y demon/rate t _m mod]n families & ev5 g5]a 7 9 exi/5ce dur+ ! ,eoc5e4 ,9 contra/ to ?is1 k ( insect evolution prior to ! ,eoc5e is r poorly kn[n4 ,scudd] 7#ahij7 & ,cock]ell 7#aibj7 h describ$ mo/ ( ! ,gre5 ,riv] insects4 ,beetles are ! mo/ common =ms1 foll[$ by dragonflies4 ,maggots & l>vae ( flies are commonly pres]v$4 ,except = ^! insects pres]v$ z :ole mummies 9 ! oil %ales1 ! majority ( ! insect fossils are pres]v$ z di/ill$ outl9es4 ,?is di/illation process result$ f ! weight & heat ( ov]ly+ s$im5ts ( driv+ (f ! volatile sub/ances f ! buri$ insects1 leav+ a hydroc>bon outl9e4 ,! process is s precise t ! f9e hairs & w+ ve9s & ev5 body-color m>k+s are pres]v$4 ,illu/ration3 ,fig4 #ac4 ,an impression ( a horse fly f ! ,fossil ,lake deposits4 ,l5g? ( orig9al1 #ab mm4 ,collection ( ,univ]sity ( ,wyom+4 ,v]tebrates ,,fi%4 ,! s+le factor t has made ,fossil ,butte _w fam\s is ! occurr5ce ( lit]ally millions ( beautifully pres]v$ fossil fi%4 ,9 "o lay] approximately #ad in*es ?ick1 ! fi% are ne>ly black & pres]v$ 9 a ne>ly :ite %ale4 ,mo/ ( ! fi% are p]fectly pres]v$1 reta9+ e detail ( ! skeleton & ev5 undi/urb$ scales4 ,fi% f ,fossil ,butte h be5 collect$ & sold s9ce ! #ahgjs & may be f\nd on sales c\nt]s1 9 museums1 & on liv+ room walls ?r\gh\t ! _w4 ,! fossil fi% f ! ,gre5 ,riv] ,=mation h a hi/ory ( discov]y /ret*+ back to #ahef4 ,at t "t ,leidy 7#ahef3bef7 describ$ a fi% giv5 to him by a ,dr4 ,john ,evans4 ,leidy call$ ! fi% ,clupea humilis1 a type ( h]r+4 ,exactly :]e ,dr4 ,evans obta9$ ! specim5 is n kn[n4 ,he pass$ ?r\gh ! area ( ! ,gre5 ,riv] ,=mation sev]al times & c\ld h collect$ x dur+ any "o ( ^? trips 7,knight #aiee3ab74 ,dur+ ! con/ruction ( ! ,union ,pacific ,railroad 9 ! #ahfjs1 workm5 bla/+ a cut ?r\gh ,gre5 ,riv] %ales1 ab\t #b miles we/ ( ,gre5 ,riv]1 ,wyom+1 came ^u rema9s ( well-pres]v$ fi%4 ,hayd5 7#ahga3gdb7 fir/ m5tions ?is cut z ,petrifi$ ,fi% ,cut4 ,_m ( ! fi% f ?is cut 7 giv5 to ,cope :o describ$ !m 9 ,hayd5's 7#ahga7 report4 ,insects1 plants1 & a bird fea!r 7 also obta9$ f ,petrifi$ ,fi% ,cut at ?is "t4 ,sometime 9 ! #ahgjs ! fir/ fi% 7 obta9$ f ,fossil ,butte itself4 ,cope 7#ahgg1 #ahgh7 describ$ fi% f ! ,gre5 ,riv] ,=mation :i* may be f ,fossil ,butte4 ,8 locality is ne>] ! ma9l9e ( ,wasat* ,m\nta9s 7,cope #ahgg3hjg74 ,?is may be ,fossil ,butte4 ,8 #ahgh locality in=mation is j z poor4 ,he does m5tion a specim5 ( ,priscac>a peali giv5 to him by ,a4 ,c4 ,peale4 ,s9ce x 0 ,peale :o fir/ wrote ab\t ,fossil ,butte1 ! specim5 may h come f ! butte4 ,peale 7#ahgi7 fir/ m5tion$ ! qu>ry+ ( fi% at ,fossil ,butte1 b he _h no specific date z to ! discov]y ( ! butte or ! beg9n+ ( qu>ry+ ( fi%4 ,cope 7#ahhd7 publi%$ two l>ge volumes ab\t ! ,t]ti>y v]tebrates ( ! ,we/4 ,"h he m5tion$ ?ree fossil localities = 8 ,gre5 ,riv] ,fi%3 ,petrifi$ ,fi% ,cut1 ,! ,m\? ( ,lab>ge ,creek1 & ,tw9 ,creek4 ,tw9 ,creek is n[ kn[n z ! ,fossil ,butte site4 ,s9ce t "t1 ! qu>ries at ,fossil ,butte h be5 ext5sively work$1 mo/ly by comm]cial collectors4 ,! fi% f ,fossil ,butte =m an unusual array ( g5]a 7,table #a7 unlike any n[ f\nd liv+ toge!r4 ,includ$ 9 ! assemblage are =ms usually f\nd 9 m>9e wat]s & tropical1 fre%-wat] fi% 7,s*aeff] & ,mangus #aife74 ,,table #a4 ,simplifi$ classification ( fi% f ,fossil ,bas94 ,elasmobran*ii ,trygonidae ,xiphotrygon 7/+ ray7 ,*ondro/ei ,polyodontidae ,polyodon 7paddle fi%7 ,holo/ei ,lepiso/eidae ,lepiso/eus 7g>7 ,amiidae ,amia 7b[f97 ,isospondyli ,o/eoglossidae ,ph>eodus ,gonorhyn*idae ,notogoneus 7s& fi%7 ,clupeidae ,diplomy/us 7h]r+s1 %ad7 ,knightia ,o/>iophysi ,siluridae ,ameiurus 7catfi%7 ,x5>*i ,aphr$od]idae 7pirate p]*es7 ,erismatopt]us ,as9eopidae ,as9eops ,acan?opt]gii ,p]cidae ,mioplosus 7p]*es7 ,s]ronidae ,priscac>a ,m ?an #dj species ( fi% h be5 describ$ f ! ,gre5 ,riv] %ales1 b au?orities d n agree on h[ _m ( ^! are valid4 ,because ( ?is1 only sup] specific gr\ps w be consid]$ 9 ! foll[+ discussion4 ,illu/ration3 ,fig4 #ad4 ,xiphotrygon1 a fossil ray4 ,^! =ms are pres5t b r r>e 9 ! fi% deposits ( ,fossil ,butte4 ,l5g? ( orig9al1 #ci cm4 ,collection ( ,univ]sity ( ,wyom+4 ,"o ( ! /range/ =ms to come f ,fossil ,butte is t ( ,xiphotrygon 7,fig4 #ad74 ,?is is n a true fi%1 b is a /+ ray1 relat$ to %>ks4 ,closely relat$ =ms /ill survive1 ) little *ange1 9 coa/al wat]s 9 _m p>ts ( ! _w4 ,l %>ks1 /+ rays h a skeleton compos$ ( c>tilage4 ,normally1 c>tilage is n pres]v$ z a fossil z x dis9tegrates readily4 ,! excell5t skeletons ( ,xiphotrygon are good evid5ce ( h[ well ! %ales ( ! ,gre5 ,riv] ,=mation pres]ve ! fossils4 ,xiphotrygon is *>act]iz$ by be+ %ort5$ f back to front & flatt5$ f top to bottom4 ,x possesses a long1 :ip-l tail & be>s enorm\s1 flat pectoral 7ant]ior7 f9s4 ,! m\? is on ! und]side ( ! body indicat+ t ,xiphotrygon1 l its mod]n relatives1 f$ along ! bottom ( ! lake4 ,! /rong flatt5$ tee? =m some?+ l a pavem5t 9 ! m\?1 sugge/+ t x f$ on clams & o!r h>d-%ell$ inv]tebrates4 ,close relatives ( ,xiphotrygon live mo/ly 9 m>9e wat]s1 b occasionally ent] fre% wat]4 ,! paddlefi%1 ,polyodon1 is r>e b pres5t at ,fossil ,butte4 ,simil> =ms /ill survive 9 ,*9a & ! ,unit$ ,/ates4 ,! prom95t features ( ,polyodon include a virtually scaleless body1 a long1 depress$ sn\t1 & long gill rak]s4 ,! skeleton1 unlike t ( mo/ mod]n fi%1 is compos$ ( c>tilage1 h5ce skeletons ( ,polyodon are r>e4 ,! diff]5ce betwe5 ! mod]n & ,eoc5e paddlefi% are s slight t ! two probably fill$ simil> or ! same ecologic ni*es4 ,?is consi/s ( fe$+ on plankton & o!r small organisms :i* c be obta9$ f ! wat]4 ,! long gill rak]s w\ld provide a l>ge surface area on :i* food c\ld be trapp$ z ! wat] pass$ out ?r\gh ! gill slits4 ,! l>ge m\? w\ld also provide a l>ge surface area = cat*+ & trapp+ food4 ,q common to /reams & riv]s ( ,nor? ,am]ica f ! ,cretace\s to ! ,rec5t is ! g>fi%1 ,lepiso/eus 7,fig4 #ae74 ,! mo/ /rik+ feature ( ! g> is its diamond-%ap$ scales1 :i* are extremely h>d & %9y4 ,! body is long1 ess5tially ( ! same dep? ?r\gh\t1 & end+ 9 a broad-bas$ tail t is slightly asymmetrical4 ,! m\? is arm$ ) _m small1 %>p tee? = cat*+ prey4 ,"o specim5 ov] #e ft long has be5 f\nd 9 ! ,fossil ,butte area4 ,illu/ration3 ,fig4 #ae4 ,! fossil g> ,lepiso/eus4 ,only a few g> h be5 f\nd at ,fossil ,butte itself4 ,l5g? ( orig9al1 #gj cm4 ,across ! highway f ! butte1 "o specim5 ov] #e ft long 0 f\nd by ,c>l ,ulri*4 ,collection ( ,univ]sity ( ,wyom+4 ,fossils ( ! b[f9 ,amia 7,fig4 #af7 are record$ f ! ,gre5 ,riv] %ales at ,fossil ,butte & 9 /ream deposits f ,cretace\s to ,rec5t4 ,?is fi% is /ill ano!r 8liv+ fossil40 ,amia is a nocturnal pr$ator4 ,presumably1 ! ,eoc5e ,amia _h simil> habits4 ,! body 9 ,amia has become elongate1 z has ! dorsal f94 ,! ?ickness ( ! scales has be5 r$uc$1 b !y are /ill r heavy & cov] ! body4 ,specim5s are r l>ge & deep-bodi$4 ,! tail f9 is ne>ly symmetrical above & bel[4 ,amia is r>e 9 ! ,fossil ,butte fi% qu>ries4 ,by f> ! mo/ abundant fi% f ,fossil ,butte is ! g5us ,knightia 7,fig4 #ag1 #ah74 ,?is fi% is a memb] ( ! ,clupeidae1 a family t includes mod]n h]r+s1 %ad1 & s>d9es4 ,! tail f9 is small relative to ! re/ ( ! body4 ,a r[ ( modifi$ scales ext5ds on ! back f ! skull to ! dorsal f94 ,possibly !y aid$ 9 /reaml9+ ! fi%4 ,knightia app>5tly f$ on ! l>ge am\nts ( plankton1 especially algae1 :i* liv$ 9 ! wat]s ( ,fossil ,lake4 ,fossils ( ,knightia are also kn[n f ,eoc5e lake s$im5ts 9 ,s\? ,am]ica4 ,knightia appe>s to h be5 susceptible to mass mortalities4 ,"s lay]s ( %ale at ,fossil ,butte conta9 lit]ally hundr$s ( ?\s&s ( ^! fi% t mu/ h suff]$ cata/rophic mass mortality4 ,possible reasons = ! obvi\s sudd5 dea? ( s _m fi% w be discuss$ 9 ! section on paleo5vironm5t & taphonomy4 ,ano!r ,eoc5e relative ( ! h]r+ f\nd at ,fossil ,butte is ,diplomy/us 7,fig4 #ai1 #bj74 ,l ,knightia1 ,diplomy/us be>s a r[ ( modifi$ scales on its back4 ,diplomy/us is ! second mo/ abundant fi% at ,fossil ,butte4 ,! jaw 9 ,diplomy/us has a r pron\nc$ oblique angle to x4 ,! deepe/ portion ( ! body is directly beh9d ! gill region1 ) a cont9u\s n>r[+ ( ! body t[>d ! tail region4 ,diplomy/us is kn[n f ,cretace\s rocks ( ,brazil & ,syria & f ,t]ti>y s$im5ts 9 ,brazil & ,we/ ,africa 7,s*aeff] & ,mangus #aife74 ,close relatives ( ,diplomy/us n[ inhabit ! wat]s (f ! coa/s ( ,p]u & ea/]n ,au/ralia4 ,illu/ration3 ,fig4 #af4 ,amia1 ! b[f94 ,?is too is r>e b pres5t at ,fossil ,butte4 ,l5g? ( orig9al1 #fg cm4 ,collection ( ,am]ican ,museum ( ,natural ,hi/ory4 ,illu/ration3 ,fig4 #ag4 ,! fossil h]r+1 ,knightia4 ,?is fi% is by f> ! mo/ abundant 9 ! fi% b$s at ,fossil ,butte & at lea/ 9 "o lay] 0 involv$ 9 a cata/rophic mass mortality4 ,l5g? ( ea* fi%1 #ac cm4 ,collection ( ,univ]sity ( ,wyom+4 ,illu/ration3 ,fig4 #ah4 ,! h]r+1 ,knightia4 ,illu/ration3 ,fig4 #ai4 ,diplomy/us1 ano!r type ( h]r+1 is ! second mo/ abundant fi% at ,fossil ,butte4 ,l5g? ( orig9al1 #ab cm4 ,collection ( ,univ]sity ( ,wyom+4 ,illu/ration3 ,fig4 #bj4 ,a l>ge ,diplomy/us ) f\r small bass1 ,priscac>a4 ,l5g? ( ,diplomy/us1 #de cm4 ,collection ( ,univ]sity ( ,wyom+4 ,ph>eodus 7,fig4 #ba7 belongs to a family ( fi%1 ! ,o/eoglossidae1 :i* began z m>9e =ms & has s9ce become a fre%-wat] family4 ,at pres5t1 !y are re/rict$ to tropical riv]s & lakes ( ,s\? ,am]ica1 ,africa1 & ,au/ralia4 ,9 ! pa/ !y _h a mu* great] di/ribution1 z its occurr5ce at ,fossil ,butte indicates1 includ+ ,nor? ,am]ica4 ,x is a deep-bodi$ fi% ) a l>ge head4 ,! anal & dorsal f9s are close to ! tail f9s4 ,! _m %>p tee? 9 ! m\? atte/ to ! c>nivor\s habits ( ,ph>eodus4 ,! family ,gonorhyn*idae1 ! liv+ s&fi% ( ! ,indo-,pacific area1 is repres5t$ at ,fossil ,butte by ,notogoneus 7,fig4 #bb74 ,notogoneus is v long-bodi$ & q sl5d]4 ,! body wid? does n v>y mu* f head to tail1 al?\gh n>r[+ does occur 9 ! tail region4 ,! tail f9 is symmetrical1 =m+ a good rudd]4 ,! anal1 dorsal1 pectoral1 & pelvic f9s are all small4 ,! body is cov]$ ) small1 elongate scales4 ,notogoneus 0 app>5tly a bottom fe$]1 liv+ on small organisms pick$ (f or out ( ! bottom ( ,fossil ,lake4 ,! ,rec5t catfi%1 ,ameuirus1 has also be5 f\nd at ,fossil ,butte 9 ! ,gre5 ,riv] %ales4 ,! =m ( ! ,eoc5e catfi% 0 v mu* l ! ,rec5t "o4 ,! habits ( ! ,eoc5e catfi% 7 probably l ^? ( ! mod]n ,ameuirus1 i4e41 adaptations to a scav5g]-type exi/5ce4 ,r common 9 ! s$im5ts ( ,lake ,gosiute1 b n yet kn[n f ! ,fossil ,bas91 is ,erismatopt]us1 a memb] ( ! family ,aphr$$]idae or pirate p]*es4 ,?is small1 elongate fi% has few di/+ui%+ *>act]s1 ! r\nd$ front edge ( ! skull be+ mo/ di/+ui%able4 ,as9eops is an ,eoc5e relative ( ,erismatopt]us & also "o ( ! pirate p]*es4 ,as9eops is1 h[ev]1 plac$ 9 a diff]5t family1 ! ,as9eopidae4 ,as9eops1 l ,erismatopt]us1 is a r pla9-look+ fi%4 ,! dorsal f9 is long relative to ! re/ ( ! body4 ,! body is slightly deep] beh9d ! gills ?an else:]e1 giv+ ,as9eops a r common appe>ance4 ,! ,p]cidae1 or p]*es1 are repres5t$ at ,fossil ,butte by ,mioplosus 7,fig4 #bc74 ,mioplosus1 z indicat$ by its well-develop$ tee?1 0 a c>nivore t probably prey$ on its pisc9e relatives 9 ,fossil ,lake4 ,! l>ge head bl5ds 9 well ) a /rongly built1 long body4 ,! anal & dorsal f9s are subequal 9 size & position$ opposite ea* o!r4 ,! tail f9 is l>ge & fan-%ap$4 ,x is easily id5tifi$ by ! pres5ce ( two dorsal f9s4 ,illu/ration3 ,fig4 #ba4 ,a l>ge ,ph>eodus1 fairly common 9 ! ,fossil ,butte fi% b$s4 ,l5g? ( orig9al1 #ed cm4 ,collection ( ,univ]sity ( ,wyom+4 ,illu/ration3 ,fig4 #bb4 ,notogoneus1 a long1 sl5d] bottom-fe$]1 occasionally f\nd at ,fossil ,butte4 ,l5g? ( orig9al1 #ef cm4 ,collection ( ,univ]sity ( ,wyom+4 ,illu/ration3 ,fig4 #bc4 ,mioplosus1 a fairly common p]* f ,fossil ,butte4 ,l5g? ( orig9al1 #cj cm4 ,collection ( ,am]ican ,museum ( ,natural ,hi/ory4 ,illu/ration3 ,fig4 #bd4 ,priscac>a1 a small bass t is common 9 ! ,fossil ,butte fi% b$s4 ,l5g? ( orig9al1 #ac cm4 ,collection ( ,univ]sity ( ,wyom+4 ,! "o g5us = :i* no close liv+ relatives c be f\nd is ,priscac>a 7,fig4 #bd74 ,! family ,priscac>idae is ?\ght to be relat$ to ! bass4 ,! family is kn[n only f ! ,eoc5e4 ,! size ( ,priscac>a is extremely v>iable4 ,! body is deep & ne>ly r\nd l t ( ! common sunfi%1 ! head bl5d+ 9 well ) ! body & its cont\rs4 ,! mo/ di/+ui%+ feature ( ,priscac>a is ! s]ies ( /rong1 /\t sp9es support+ ! anal & dorsal f9s4 ,^! sp9es may h act$ z cut-wat]s = bett] swimm+ &_/or !y may h protect$ ,priscac>a f its m voraci\s relatives4 ,,amphibians4 ,to date1 no amphibian fossils are kn[n f ,fossil ,butte4 ,!y mu/ h be5 pres5t1 z ?is class ( animals is record$ f ,devonian rocks m ?an #cej million ye>s old & f rocks y\ng] ?an ^? at ,fossil ,butte4 ,liv+ amphibians are typifi$ by frogs1 toads1 & salam&]s4 ,! lack ( amphibian rema9s at ,fossil ,butte is m likely due to nondiscov]y ?an nonexi/5ce4 ,,reptiles4 ,reptile fossils are v abundant 9 ! ,gre5 ,riv] & ,wasat* =mations4 ,also a jaw ( ! ?ree-horn$ ,tric]atops is kn[n f ! ,cretace\s "p ( ! ,evan/on ,=mation4 ,small liz>ds are normally repres5t$ only by jaw fragm5ts & v]tebrae4 ,_! rema9s are mo/ (t5 f\nd by a process ( wa%+ & scre5+ ( ! s$im5ts conta9+ ! fossils4 ,snakes are also repres5t$ 9 ! ,gre5 ,riv] ,=mation4 ,rema9s ( ^! animals are also (t5 re/rict$ to jaws & v]tebrae4 ,a complete skeleton ( a fossil boa1 ,boavus idelmani1 has be5 recov]$ f ! ,gre5 ,riv] ,=mation & is ! mo/ complete fossil snake f ,nor? ,am]ica 7,s*aeff] & ,mangus #aife74 ,turtles are among ! mo/ abundant reptile fossils4 ,!y are usually f\nd z isolat$ %ell plates1 al?\gh _m complete %ells are kn[n4 ,! turtles ,trionyx 7,fig4 #be71 ,emys1 ,ba5a1 & ,notomorpha are kn[n f ! ,fossil ,bas94 ,! l>ge/ ,eoc5e reptiles 7 ! crocodiles 7,fig4 #bf74 ,! pres5ce ( ^! pr$ace\s animals is fur!r evid5ce = a prevail+ w>m & humid climate dur+ ! ,eoc5e times s9ce _! tol]ance ranges include only comp>able conditions at ! pres5t "t4 ,a few incomplete specim5s h be5 recov]$ f ne> ! monum5t4 ,,birds4 ,birds1 :i* fir/ appe>$ 9 ,jurassic "t1 are r>e z fossils 9 rocks ( any age because _! skeletal rema9s are exce$+ly fragile4 ,_! fossilization requires special conditions because _m ( _! bones are holl[ z a weight-r$uc+ adaptation = flight4 ,^! holl[ bones are especially susceptible to breakage & poor pres]vation4 ,scatt]$ rema9s ( birds1 mo/ly limb bones1 are f\nd 9 ! ,gre5 ,riv] s$im5ts4 ,fea!r impr9ts h also be5 recov]$4 ,a complete skeleton ( ,gall9uloides1 a bird relat$ to ! ,s\? ,am]ican f[l-l *a*alaca1 is "o ( ! mo/ significant f9ds f ! ,gre5 ,riv] ,=mation4 ,rec5tly1 ,brodkorb 7#aigj7 describ$ ! w+s ( puff birds simil> to ^? n[ liv+ 9 ,s\? ,am]ica f ne> ,fossil ,butte4 ,illu/ration3 ,fig4 #be4 ,an aquatic turtle1 ,trionyx1 f ! %ore-l9e deposits ( ,lake ,gosiute4 ,sev]al turtles h be5 f\nd 9 ! fi% b$s ne> ,fossil ,butte4 ,illu/ration3 ,fig4 #bf4 ,! skull ( a l>ge crocodile f ne> ! %orel9e ( ,lake ,gosiute4 ,sev]al crocodile fragm5ts h be5 f\nd at ,fossil ,butte b$s4 ,l5g? ( orig9al1 #ge cm4 ,collection ( ,univ]sity ( ,wyom+4 ,9 ! adjac5t ,gre5 ,riv] ,bas9 to ! ea/1 paleontologi/s f ! ,univ]sity ( ,wyom+ h f\nd ne/+ gr\nds ( ,eoc5e flam+os 9 slightly y\ng] s$im5ts ( ! ,gre5 ,riv] ,=mation4 ,^! 8rook]ies0 h yield$ _m hundr$s ( fossil bones ( ?is curi\s bird4 ,s9ce ^! bird fossils 7 f\nd proximal to ,fossil ,butte1 !y demon/rate ! ne> subtropical nature ( ! environm5t 9 ! ,fossil ,butte area 9 ,gre5 ,riv] times4 ,,mammals4 ,! rocks ( ! ,evan/on1 ,wasat*1 & ,f[kes =mations conta9 v>i\s fossiliz$ rema9s ( mammals :i* once inhabit$ ! ,fossil ,bas94 ,mammal fossils are highly significant s9ce !y are us$ ext5sively = correlation & dat+ ( ! ,t]ti>y rocks ( ! ,we/4 ,fossils :i* are readily recognizable1 limit$ 9 "t1 & widely di/ribut$ geographically are call$ 8index fossils40 ,^! fossils are re/rict$ to a p>ticul> "t horizon 9 ! rock4 ,9 ?is way1 rocks ( unkn[n age :i* are f\nd to conta9 index fossils c be dat$ relatively & h5ce correlat$ ) o!r fossil-be>+ rocks4 ,! small condyl>? ,haplomylus 7,fig4 #bg7 is a v e>ly ,eoc5e index fossil4 ,its pres5ce 9 c]ta9 s$im5ts 9 ! ,fossil ,bas9 %[s conclusively t ^! s$im5ts 7 laid d[n 9 e>lie/ ,eoc5e times4 ,illu/ration3 ,fig4 #bg4 ,a jaw ( ! primitive mammal ,haplomylus4 ,l5g? ( orig9al1 #a4c cm4 ,collection ( ,univ]sity ( ,wyom+4 ,! mammal fossils f\nd 9 ,fossil ,bas9 are also important 9 docum5t+ ! temporal *anges 9 evolution & environm5t ( ! biotic community4 ,! picture ( ,eoc5e ,wyom+ drawn ?r\gh int]pretation ( ^! fossils is va/ly diff]5t ?an t ( ! pres5t day4 ,mammals h a long evolution>y hi/ory t began ov] #bjj million ye>s ago 9 ! ,triassic p]iod4 ,at t "t mammals _h only j evolv$ f _! reptilian ance/ors4 ,^! e>lie/ mammals 7 small1 furtive creatures4 ,h[ev]1 ) ! ext9ction ( ! d9osaurs "s #fe million ye>s ago at ! end ( ! ,cretace\s1 ! mammals 7 able to div]sify rapidly & fill ! empty ecologic ni*es t ! d9osaurs once occupi$4 ,?is fill+ ( ecologic ni*es void$ by ! d9osaurs c\pl$ ) ! spread+ ( mammals into hi!rto unoccupi$ ni*es result$ 9 ! developm5t ( a l>ge v>iety ( mammals4 ,"s became ext9ct1 o!rs 7 ! ance/ors ( mod]n mammals4 ,fossils ( mammals f\nd 9 s$im5ts 9 ! ,fossil ,bas9 are pro( ( ! ext5t ( ?is ,late ,cretace\s-e>ly ,t]ti>y mammal radiation4 ,e>ly mammals bore little resemblance to _! lat] desc5dants4 ,g5]al tr5ds 9 mammalian evolution 7 increase 9 size & ! t5d5cy to become m 8mod]n0-look+ ?r\gh adaptation to *ang+ ,t]ti>y environm5ts4 ,mo/ mammal fossils are extremely fragm5t>y4 ,tee? are mo/ (t5 pres]v$ z !y are ! h>de/ "p ( ! skeleton & !re=e mo/ resi/ant to we> & breakage4 ,?us1 x (t5 happ5s t ! k ( a p>ticul> fossil mammal is d]iv$ entirely f its pres]v$ d5tition4 ,?is has obvi\s limitations = ! complet5ess ( our und]/&+ ab\t mammals 9 "q4 ,! ,paleoc5e portion ( ! ,evan/on ,=mation has yield$ mammals ( ,torrejonian & ,tiffanian age 7,fig4 #f74 ,! ,torrejonian assemblage 7middle ,paleoc5e7 7,gaz9 #aifi7 is small & poorly pres]v$4 ,its ma9 significance is t ! fauna records a def9ite "t int]val = ! ,evan/on ,=mation4 ,gaz9's "w has demon/rat$ ?is fauna to be int]m$iate 9 composition betwe5 simil>ly ag$ faunas recov]$ f sites to ! nor? & s\?4 ,! major faunal elem5ts are insectivores1 primates1 condyl>?s 7primitive ungulates71 & multitub]culates 7a type ( ext9ct rod5t-l mammal1 ) no kn[n desc5dants74 ,! poorly pres]v$ condition ( ^! fossils makes discussion impossible except to note t !y ext5d ! kn[n "t range ( mammalian habitation 9 ! ,fossil ,bas94 ,! y\ng] ,tiffanian fauna 7late ,paleoc5e7 7,gaz9 #aief7 is also kn[n f l>gely fragm5t>y rema9s4 ,! multitub]culate mammal ,ptilodus1 also pres5t 9 ,torrejonian deposits1 is ! mo/ 8primitive0 mammal 9 ! fauna4 ,! multitub]culates fir/ appe>$ 9 ! ,jurassic 7,fig4 #d71 & are !re=e ! olde/ l9eage ( mammals t surviv$ into ,t]ti>y times4 ,! mol> tee? ( ^! animals are *>act]iz$ by multiple cusps arrang$ 9 p>allel r[s4 ,ptilodus1 l mo/ o!r multitub]culates1 0 specializ$ 9 t its f\r? l[] premol>s 7 exp&$ into %e>+ blades1 ! function ( :i* is n kn[n4 ,ptilodus 0 9 _m respects simil> to rod5ts 9 ! developm5t ( procumbant incisors & 9 g5]al build & appe>ance4 ,multitub]culates are1 h[ev]1 n relat$ to rod5ts except t bo? are mammals4 ,! diff]5tiation ( rod5ts 9 ! late ,paleoc5e & _! div]sification dur+ ! ,eoc5e probably pres5t$ /rong competition = ! multitub]culates :o 7 unable to compete successfully & s became ext9ct4 ,! primates 7 repres5t$ by ,plesiadapsis4 ,?is animal 0 ab\t ! size ( a squirrel & _h *isel-l incisors4 ,fle% recon/ructions ( ,plesiadapsis1 bas$ on skeletal rema9s1 %[ ?is primate to look mu* l a rod5t ) a long-sn\t$ skull1 claw$ feet1 long body1 & tail4 ,!re is conceivable relation%ip betwe5 ! rod5ts & ,plesiadapsis-l primates4 ,! dom9ant ,tiffanian h]bivor\s mammals 7 memb]s ( ! ,ord] ,condyl>?ra4 ,^! primitive ungulates 7 div]se 9 bo? size & appe>ance4 ,x is probable t lat] mod]n ungulates 7,artiodactyla1 ,p]issodactyla7 evolv$ f ! ,condyl>?ra2 h[ev]1 !re are no surviv+ memb]s ( ?is gr\p4 ,! ,paleoc5e condyl>?s 7 mo/ly small animals & include su* =ms z ,haplaletes1 ,litomylus1 & ,gidley9a4 ,^! mammals _h some:at insectivore-l tee?1 & may h bridg$ ! gap betwe5 insectivores & ar*aic ho($ mammals4 ,"o ( ! l>g] ,tiffanian condyl>?s 0 ,ph5acodus4 ,?is mammal _h a long1 massive skull & a long1 probably flexible body4 ,! limbs 7 /\t & %ort4 ,! body end$ 9 a long tail4 ,small hooves 7 pres5t on all digits1 :i* numb]$ five p] foot4 ,! l5g? ( ! l>ge/ ,ph5acodus 0 ab\t #f ft4 ,c>nivor\s & omnivor\s condyl>?ra 7 also common4 ,?ryptacodon & ,cla5odon are two types kn[n f ! ,evan/on ,=mation 9 ! ,fossil ,bas94 ,! true c>nivores 7,ord] ,c>nivora7 7 also pres5t4 ,! ,paleoc5e c>nivores 7 small & possibly arboreal 9 habit4 ,! /em c>nivore /ock 0 repres5t$ by ! family ,miacidae4 ,9 ! ,fossil ,bas9 ! miacid ,didymictis 0 common4 ,9 ,didymictis1 ! m\? 0 arm$ ) small1 %>p tee?4 ,mo/ important1 ! typical c>nivoran c>nassial 7%e>+7 tee? _h develop$4 ,among c>nivores1 f ,paleoc5e to ,rec5t1 ! %e>+ blades develop$ on ! la/ upp] premol> & ! fir/ l[] mol>s4 ,v>i\s k9ds ( %e>+ tee? h evolv$ 9 o!r mammal l9eages4 ,mammals f ! ,wasat* ,=mation 9 ,fossil ,bas9 repres5t ! ,greybullian & ,lysitean prov9cial ages 7see ,fig4 #f74 ,^! fossils are ( e>lie/ ,eoc5e & mid to e>ly ,eoc5e age4 ,fossil localities 9 ! ,wasat* ,=mation ( s\?we/]n ,wyom+ are ,knight ,/ation 7p>tly ,lysitean71 at ,elk ,m\nta9 7,greybullian71 & at ,fossil ,butte itself4 ,! age ( ! ,wasat* ,=mation at ,fossil ,butte is ,lysitean4 ,! insectivores are repres5t$ by ,diacodon1 a small mammal kn[n only f fragm5t>y mat]ial4 ,primates also cont9u$ to exp& & div]sify 9 ,wasat*ian "t4 ,microsyops 0 a v unusual type t belongs to ! ext9ct family ,microsyopidae4 ,! tee? 7 %>p & adapt$ = eat+ fruit &_/or insects4 ,microsyops 0 ab\t ! size ( a rat or slightly l>g]4 ,! microsyopid primates 7 limit$ to ! ,paleoc5e & ,eoc5e & left no lat] kn[n desc5dants4 ,ano!r gr\p ( primates is repres5t$ by ,pelycodus4 ,?is 0 a small lemur-l animal t may possibly h be5 an ance/or ( high] primates 7monkeys1 apes1 & m574 ,pelycodus1 l ,microsyops1 0 an arboreal 7tree-dwell+7 animal :i* inhabit$ ! =e/s ( ! ,fossil ,bas9 dur+ ! e>ly ,eoc5e4 ,! ,ord] ,ta5iodonta is a /range & little kn[n gr\p ( mammals4 ,9 ! s$im5ts at ,fossil ,butte ! ta5iodonts are repres5t$ by ,ectoganus4 ,?is 0 a mod]ately l>ge animal4 ,! skeletal adaptations 7 simil> to ^? ( moles1 b !re 0 no actual relation%ip betwe5 ! two gr\ps4 ,! front feet & legs 7 robu/1 & bore l>ge claws4 ,ectoganus probably us$ ^! /ructures to grub = food1 possibly roots4 ,! incisor tee? 7 rootless & p]si/5tly gr[+4 ,! too? enamel 0 re/rict$ to two b&s on ei!r side ( ! tee?4 ,! s+le pair ( upp] & l[] incisors 0 greatly enl>g$4 ,! ta5iodonts became ext9ct 9 ! ,eoc5e & left no desc5dants4 ,equally z /range a gr\p ( animals z ! ta5iodonts are mammals 9 ! ,ord] ,tillodonta4 ,^! 7 h]bivor\s animals1 "s ( :i* became q l>ge4 ,!y h _m rod5t-l *>act]s1 b 7 n relat$ to rod5ts4 ,9 _m respects1 ! morphology ( rod5ts seems to h l5t itself to conv]g5ce4 ,e/honyx 0 ! mo/ common tillodont f ! ,fossil ,bas94 ,prom95t1 rootless incisors 7 a *>act]i/ic ( ! lat] memb]s ( ! gr\p4 ,^! incisors 7 *isel-l1 z 9 rod5ts4 ,! mol>s 7 unusual & bore c]ta9 resemblances to primitive c>nivoran & insectivoran tee?4 ,! tillodonts1 h[ev]1 bore unc]ta9 relation%ips to o!r mammals & left no desc5dants beyond ! middle ,eoc5e4 ,9 comp>ison ) rec5t faunas1 ,paleoc5e rod5ts 7 r>e faunal elem5ts4 ,two e>ly rod5ts 7 f\nd 9 ! ,fossil ,bas9 ,wasat* ,=mation3 ,p>amys 0 relatively unspecializ$ b 0 div]se 9 ! numb] ( species4 ,"o species ( ,p>amys 0 ab\t #b ft long & possess$ a long tail4 ,! body 0 long & sl5d]4 ,! skull 0 small & r squirrel-l4 ,! *eek tee? 7 quadrate & _h l[1 blunt cusps4 ,! typical1 s+le pair ( *isel incisors 0 pres5t bo? on l[] & upp] jaws4 ,p>amys 0 probably an arboreal =m t did n look too unlike a mod]n squirrel & may h _h a simil> mode ( life4 ,ano!r rod5t1 ,rei?rop>amys1 0 some:at simil> to ,p>amys 9 size & appe>ance4 ,! diff]5ces betwe5 ! two animals 7 ma9ly 9 ! tee? & h9d limbs4 ,! latt] %[$ c]ta9 v m9or /ructural modifications t sugge/$ a saltatorial 7jump+7 mode ( locomotion = ,rei?rop>amys4 ,bats 7,ord] ,*iropt]a7 are extremely r>e z fossils because _! volant & cave-dwell+ habitat z well z a fragile skeleton did n l5d _! rema9s to pres]vation4 ,f ! ,gre5 ,riv] ,%ales1 f ne> ,fossil ,butte1 a complete articulat$ skeleton ( a bat has be5 f\nd 7,jeps5 #aiff74 ,?is animal1 nam$ ,c>onyct]is index1 0 small & g5]aliz$ 9 =m4 ,sup]ficially1 x look$ mu* l a typical br[n bat4 ,?is fossil is important because x demon/rates t ! bats _h already become good fli]s by e>ly ,eoc5e "t4 ,! condyl>?s 7 prom95t 9 ! e>ly ,eoc5e b dim9i%$ 9 importance foll[+ ?is "t4 ,ph5acodus 0 /ill extant2 h[ev]1 x 0 replac$ 9 importance by ! small] ,hyopsodus4 ,hyopsodus is p]haps ! mo/ commonly recov]$ ,eoc5e fossil mammal4 ,?is animal 0 small & long-bodi$ & reta9$ a m-or-less g5]aliz$ /ructural patt]n4 ,9 "s respects ,hyopsodus 0 simil> to bo? insectivores & primates & 0 at "o "t or ano!r reg>d$ z belong+ to ei!r ( ^! two ord]s4 ,"s ( ! lat] condyl>?s p>allel$ ! m advanc$ ungulates4 ,inde$1 ! ,p]issodactyla 7horses1 tapirs1 rh9os7 & ,artiodactyla 7bovids1 de]1 pigs1 %eep1 etc47 7 d]iv$ f e>ly ,t]ti>y condyl>?s4 ,m5isco!rium 0 "o su* advanc$ condyl>?4 ,! cusps on its mol>s1 in/ead ( be+ blunt po9ts1 _h develop$ into cresc5tic patt]ns1 some:at l ^? 9 de] or camels4 ,! relation%ip ( ,m5isco!rium to mod]n ungulates is only "o ( p>allel d5tal developm5t4 ,m5isco!rium 0 a m$ium-siz$ animal1 b ab\t ! same build & size z t ( a cock] spaniel4 ,m5isco!rium1 h[ev]1 _h ho(s on its toes & 0 a =e/-liv+ br[s]4 ,! condyl>? ,haplomylus is f\nd at ! ,elk ,m\nta9 ,wasat*ian locality4 ,?is small animal is typical ( ! ,greybullian level ( faunal organization 7e>lie/ ,eoc5e74 ,a suppos$ c>nivor\s condyl>? 0 ,pa*ya5a4 ,pa*ya5a 0 a fairly l>ge animal = its "t4 ,! /rong1 robu/ jaws & tee? & heavy build sugge/ t ,pa*ya5a 0 a pr$atory animal suit$ = prey+ on l>g] animals su* z ! amphibi\s pantodont ,coryphodon4 ,! aff9ities ( ,pa*ya5a to ! condyl>?s are unc]ta9 & are bas$ prim>ily on foot /ructure4 ,! miacid c>nivores 7 abundant & v>i$4 ,didymictis p]si/$ & bo? ,vassacyon & ,vulpavus cont9u$ ! arboreal1 =e/-dwell+ habits ( _! ,paleoc5e precursors4 ,! ma9 c>nivor\s animals ( ! ,eoc5e1 h[ev]1 7 ! creodonts 7,ord] ,creodonta7 :i* 7 ess5tially e>ly exp]im5t]s 9 c>nivor\s habits4 ,z su* !y 7 div]sely specializ$4 ,proviv]ra 7,s9opa7 0 "o ( ! small]1 pr$ace\s creodonts t inhabit$ ,fossil ,bas9 dur+ ,eoc5e times4 ,"o ( ! mo/ *>act]i/ic fossil mammals f ! e>ly ,eoc5e ( ,fossil ,bas9 0 ,coryphodon4 ,a specim5 ( ,coryphodon 0 also ! fir/ mammal fossil to be f\nd 9 ! ,fossil ,bas94 ,! ord] ( mammals to :i* ,coryphodon belongs1 ! ,pantodonta1 0 a gr\p ( l>ge & heavily built1 h]bivor\s mammals4 ,coryphodon 0 ab\t ! size ( a small rh9oc]os4 ,! skull 0 l>ge & heavily built4 ,! bra91 h[ev]1 0 small4 ,! can9e tee? 7 some:at enl>g$ & /rong4 ,/\t limbs support$ ! bulky body4 ,9 habits1 ,coryphodon 0 possibly semi-aquatic4 ,! mod]n ungulates1 ,ord] ,p]issodactyla 7odd-to$ ungulates7 & ,ord] ,artiodactyla 7ev5-to$ ungulates71 fir/ appe>$ 9 ! e>ly ,eoc5e4 ,! e>lie/ memb]s ( bo? ord]s 7 small & relatively unspecializ$4 ,! e>lie/ p]issodactyls 7 ! horses & tapirs4 ,! e>lie/ horses 7 repres5t$ by ,hyraco!rium4 ,?is small1 sl5d]1 & lightly built horse 0 ab\t ! size ( a fox t]ri]4 ,! front feet _h f\r toes1 & ! h9d feet ?ree toes4 ,! tee? sugge/ t ?is animal 0 probably a br[s]1 liv+ 9 ! =e/s4 ,9 ! ,fossil ,bas91 tapirs 7 kn[n f deposits ( ,lysitean 7mid to e>ly ,eoc5e7 age ( :i* ,heptodon 0 repres5tative4 ,! tapirs n[ live 9 ! tropics ( ,malaysia & ,lat9 ,am]ica4 ,_! pres5t habitat sugge/s a simil> environm5t may h be5 favor$ by ! ,eoc5e tapirs ( ! ,fossil ,bas94 ,! fir/ ,artiodactyls 7 pig-l =ms1 al?\gh !y are only di/antly relat$ to true suids4 ,protodi*obune 0 small & may h look$ mu* l "s ( ! e>ly ,p]issodactyls4 ,!re are1 h[ev]1 a complex ( /ructural features :i* s]ve to di/+ui% ^! mammalian ord]s f ea* o!r4 ,! mammal fauna f ! ,f[kes ,=mation places a late ,bridg]ian age on ! ,sillem & ,bulldog ,holl[ memb]s 7,nelson #aigc74 ,small mammals 7 mo/ abundant 9 ! ,f[kes1 especially primates & rod5ts4 ,! m>supials 7 *>act]iz$ by ,p]a!rium :i* 0 a small1 probably arboreal1 opossum-l animal4 ,p]a!rium 0 b "o /age 9 a sl[ & relatively cons]vative evolution ( opossums t began 9 ! ,cretace\s4 ,! condyl>?s decreas$ 9 importance dur+ ,f[kes "t & 7 gradually replac$ by m advanc$ ungulates1 ! artiodactyls & p]issodactyls4 ,only ! small ,hyopsodus surviv$ into ! ,bridg]ian ( ! ,fossil ,bas94 ,! horses cont9u$ to diff]5tiate z evid5c$ by ! appe>ance ( ,orohippus1 an animal simil> to ,hyraco!rium1 b ) m9or d5tal diff]5ces4 ,! primitive tapirs 7 repres5t$ by ,hyra*yus1 a m$ium-siz$ h]bivore :i* 0 ne>ly z closely relat$ to ! rh9oc]oses z x 0 to ! tapirs4 ,! primates 7 also div]se 9 ,f[kes "t2 h[ev]1 ?is gr\p began to decl9e 9 importance foll[+ ,bridg]ian times4 ,z a gr\p1 ! primates 7 re/rict$ ma9ly to w>m & =e/$ environm5ts4 ,! lemur-l ,no?>ctus & ! t>si]-l ,omomys & ,hemiacodon 7 common 9 ! ,f[kes4 ,hemiacodon 0 typical ( ! late ,bridg]ian 7an index fossil74 ,! true c>nivores1 repres5t$ by ,miacis1 rema9$ small 9 size1 p]haps to avoid competition ) ! l>g] surviv+ creodonts4 ,insectivores f ! ,f[kes ,=mation are abundant & v>i$4 ,un=tunately1 !y are kn[n almo/ exclusively f tee?4 ,f[kes insectivores include ! h$ge-hog-l ,nycti!rium1 ,talpavus1 & ,sc5opagus4 ,apatemys is an insectivore ( unc]ta9 aff9ities4 ,! fe$+ habits ( ^! e>ly insectivores 7 probably simil> to ^? ( contempor>y insectivore species 7moles & %rews72 h[ev]1 !re is "s evid5ce to sugge/ _m ( ^! small creatures may h be5 semi-arboreal4 ,"o ( ! mo/ unusual ( middle ,eoc5e creatures is ! giant ,u9ta!rium4 ,?is 0 a l>ge br[s+ animal1 ab\t ! size ( a rh9oc]os4 ,:at 0 mo/ unusual ab\t ,u9ta!rium 0 its skull :i* 0 l>ge & /rongly built4 ,! l>ge upp] can9es 7 app>5tly =midable def5sive weapons4 ,! skulls ( ! males bore six prom95t bony protub]ances :i* grew f ! frontal region ( ! skull4 ,! function ( ^! /ructures is unkn[n4 ,!y may h be5 ( use = def5se4 ,dur+ ,bridg]ian times1 ! rod5ts und]w5t an explosive adaptive radiation :i* ultimately may h l$ to ! ne> ext9ction ( ! less well-adapt$ multitub]culates4 ,! div]sity ( ,bridg]ian rod5ts f ,fossil ,bas9 is impressive4 ,species ( ,leptotomus1 ,p>amys1 ,?isbemys1 ,microp>amys1 ,sciuravus1 ,mysops1 & ,pauromys demon/rate t a wide range ( adaptations ( environm5ts 0 exploit$ by ! rod5ts4 ,?is div]sity 9 life habits has be5 a m>k ( rod5t evolution f ! middle ,eoc5e to ! pres5t day4 ,! above descriptions ( ! kn[n mammal fossils f ! ,fossil ,butte area are int5d$ to demon/rate ! v>i$ life =ms t once exi/$ 9 s\?we/]n ,wyom+4 ,fur!r collect+ w almo/ c]ta9ly exp& ! numb] ( fossil mammal species f ,fossil ,bas9 & increase our k ( ! succession ( anci5t environm5ts :i* prevail$ at diff]5t times 9 ! ,fossil ,bas9 area4 ,,table #b4 ,mammals kn[n f ,fossil ,bas9 ,faunal li/s--,middle ,paleoc5e3 ,torrejonian ,class ,mammalia ,multitub]culata ,ptilodus ,neoplagiaulax ,ectypodus ,insectivora ,leptacodon ,aphronorus ,primates ,torrejonia ,prono?odectes ,condyl>?ra ,*riacus ,tric5tes ,promiocla5us ,litaletes ,haplaletes ,late ,paleoc5e3 ,tiffanian ,multitub]culata ,ptilodus8 ,primates ,plesiadapis ,condyl>?ra ,?ryptacodon ,cla5odon ,litomylus ,haplaletes ,gidley9a ,ph5acodus ,c>nivora ,didymictis ,pantodonta ,g5us indet]m9ant4 ,e>ly ,eoc5e3 ,graybullian ,primates ,pelycodus ,tillodontia ,e/honyx ,rod5tia ,p>amys ,creodonta ,proviv]ra ,c>nivora ,didymictis ,vassacyon ,condyl>?ra ,pa*ya5a ,haplomylus ,hyopsodus ,ph5acodus ,m5isco!rium8 ,pantodonta ,coryphodon ,p]issodactyla ,hyraco!rium ,artiodactyla ,diacodexis ,e>ly ,eoc5e3 ,lysitean ,insectivora ,diacodon ,primates ,pelycodus ,microsyops ,tillodontia ,e/honyx ,rod5tia ,p>amys ,rei?rop>amys ,creodonta ,proviv]ra ,c>nivora ,didymictis ,vulpavus ,condyl>?ra ,pa*ya5a8 ,hyopsodus ,ph5acodus ,m5isco!rium8 ,pantodonta ,coryphodon ,p]issodactyla ,hyraco!rium ,heptodon ,artiodactyla ,protodi*obune ,e>ly ,eoc5e3 ,wasat*ian 7g5]al7 ,*iropt]a ,ic>onyct]is ,late ,middle ,eoc5e3 ,late ,bridg]ian ,m>supialia ,p]a!rium ,insectivora ,apatemys ,nycti!rium ,sc5opagus ,talpavus ,primates ,hemiacodon ,omomys ,no?>ctus ,condyl>?ra ,hyopsodus ,rod5tia ,leptotomus ,microp>amys ,mysops ,p>amys ,pauromys ,sciuravus ,?isbemys ,d9oc]ata ,u9ta!rium ,p]issodactyla ,orohippus ,hyra*yus ,,paleoecology ,,& ,,taphonomy ,paleoecology is ! /udy ( anci5t biotic communities & _! relation%ip to ! abiotic environm5t4 ,! conclusions ( paleoecology are rea*$ by /udy+ 9 detail ! fossils & s$im5ts & :atev] relation%ips exi/ betwe5 !m4 ,its ultimate aim is to build a picture ( ! climate1 flora1 fauna1 & topographic sett+ ( an area4 ,= ?is reason x borr[s heavily f paleontology1 paleobotany1 s$im5tology1 & climatology4 ,f /udy+ mod]n environm5ts1 x is obs]v$ t ea* has its own type ( s$im5t4 ,:5 c]ta9 s$im5ts are f\nd 9 ! rock record1 x is g5]ally assum$ t !y repres5t environm5ts simil> to mod]n ones t produce simil> deposits4 ,= example1 lime/one is =m+ today 9 w>m1 %all[1 well-light$1 well-a]at$ wat]4 ,:5 lime/one is f\nd 9 a rock sequ5ce1 x is usually assum$ t ! same or simil> environm5tal conditions occurr$ 9 t area 9 ! pa/4 ,fossils c fur!r ref9e ! int]pretation4 ,z c be int]pret$ f =ego+ discussions1 ! s$im5ts deposit$ 9 ! ,fossil ,bas9 v>y f /ream & flood-pla9 fluvial to lacu/r9e4 ,at times1 mat]ial erod$ f surr\nd+ upl&s 0 c>ri$ by /reams ?r\gh\t ! bas94 ,^! rocks are exemplifi$ by ! ,evan/on & p>ts ( ! ,wasat* & ,f[kes =mations4 ,:5 ! lake appe>$1 lacu/r9e s$im5ts1 m>l/one1 & %ale 7 deposit$ 9 ! lake1 :ile ar\nd ! p]iph]y ( ! bas91 fluvial s$im5ts cont9u$ to accumulate4 ,plants f\nd 9 ! lake s$im5ts ( ,fossil ,bas9 tell u mu* ab\t ! climatic conditions t prevail$ dur+ ! ,eoc5e4 ,! flora is q simil> to t n[ exi/+ 9 ! s\!a/]n ,unit$ ,/ates1 reflect+ a w>m & humid climate4 ,"o ( ! /rik+ examples is t ( huge palm fronds t occasionally are f\nd 9 ! fi% qu>ries at ,fossil ,butte4 ,^! seem to be fronds t blew f ! trees into ! lake4 ,soon !y became wat]-logg$ & settl$ to ! bottom to be pres]v$4 ,! l& animals indicate t a r wide range ( ecologic ni*es exi/$ ov] ! bas9 be=e ! lake came into be+1 ar\nd ! lake dur+ its pres5ce1 & aga9 all ov] ! bas9 aft] ! lake disappe>$4 ,_m ( ! small] mammals1 "s ( ! rod5ts1 & mo/ ( ! primates 7 almo/ c]ta9ly arboreal4 ,! l>ge mammals su* z u9ta!res1 pantodonts1 & tapiroids may h be5 /ream-side or m>% dwell]s4 ,probably inhabit+ ! =e/ floor & fe$+ on l[ bu%es & und]gr[? 7 su* =ms z ! condyl>?s1 horses1 artiodactyls1 & "s ( ! rod5ts4 ,fe$+ on ! rod5ts & o!r small] mammals 7 ! creodonts & miacids4 ,t9y %rew-l =ms scamp]$ ab\t ! und]gr[? & f$ ^u worms & insects4 ,bradley 7#aifc7 has e/imat$ possible temp]ature & precipitation levels 9 s\?we/]n ,wyom+ dur+ ! ,eoc5e4 ,bradley's mod]n analogues 7 ! ,gulf ,coa/ & ,great ,lakes regions4 ,f a s]ies ( calculations1 an av]age annual temp]ature ( #fe;,f is po/ulat$4 ,?is c\ld h fluctuat$ greatly 9 ! inl& sett+ ( ,fossil ,bas94 ,precipitation am\nts 7 possibly on ! ord] ( #cj-dc in*es annually4 ,! am\nt ( annual evaporation 0 also possibly 9 ! range ( #cj-dc in*es4 ,x is believ$ t ,fossil ,lake 0 !rmally /ratifi$--t is1 ) cold]1 d5s] wat] at dep? 7hypolimnion7 & w>m]1 less d5se wat] 7epilimnion7 ne>] ! surface4 ,! deep] wat]s probably w\ld h be5 devoid ( oxyg51 h5ce ess5tially un9habit$ o!r ?an by ana]obic bact]ia t survive )\t oxyg54 ,if ! bottom _h be5 oxyg5at$1 _m types ( life w\ld h burr[$ into ! s$im5t ?us de/roy+ ! delicate v>ves 7,fig4 #bh74 ,! lake 0 probably deep en\gh t w9d & wave action did n roil ! bottom s$im5ts4 ,illu/ration3 ,fig4 #bh4 ,a section ( %ales f ! fi% b$s %[+ ?9 lam9ae t are int]pret$ z v>ves4 ,enl>g$ six times4 ,!re h be5 _m attempts to int]pret ! taphonomy 7see gloss>y7 ( conc5trations ( fi% at ,fossil ,butte4 ,bradley 7#aidh7 int]pret$ ! cause ( dea? & ! reason = _! pres]vation z foll[s3 ,9 ?is bas9 7,fossil1 ,wyo47 hundr$s ( ?\s&s ( beautifully pres]v$ fi% are entomb$ 9 ! v>v$ s$im5ts4 ,ev5 ! delicate f9 & tail rays & o!r bones orig9ally held 9 place only by tissue are virtually undi/urb$1 & ev5 ! scales are 9 place almo/ completely undi/urb$4 ,x seems to me t ! picture ( ?is lake z a !rmally /ratifi$ wat] body provides ne>ly all ! necess>y in=mation to acc\nt = ! excell5t pres]vation ( ^! fi%4 ,only 9 ! /agnant hypolimnion c\ld !y h escap$ be+ torn to pieces by scav5g]s or di/ort$ by bottom fe$]s4 ,x is significant t all ! well pres]v$ fi% are 9 v>v$ s$im5ts4 ,^? 9 non-v>v$ s$im5ts are a disord]$ mass ( brok5 & *ew$ up bones4 ,! only "p ( ! /ory lack+ n[ is h[ ! fi% di$ & got into ! hypolimnion4 ,limnology (f]s two possible explanations4 ,sometimes :5 ! surface ( a lake gets excessively w>m1 fi% w plunge into deep wat] & might ?us p5etrate ! hypolimnion1 be ov]come by hydrog5 sulphide1 & also h ! gas 9 _! swim bladd]s *ill$ s t !y sank at once to ! bottom4 ,once !re1 only ana]obic bact]ia w\ld attack !m4 ,! o!r hypo!sis is t ! !rmally /ratifi$ lake 0 sudd5ly *ill$ s t x ov]turn$ m rapidly ?an ! hydrog5 sulphide c\ld be oxydiz$ & s kill$ (f l>ge numb]s ( fi%4 ,?is seems a little m probable z ! fossil fi% are ( all ages & sizes4 ,! fi% 9 ^! qu>ries h be5 collect$ s9ce ! #ahgjs b ma9ly by comm]cial collectors4 ,mo/ museum collections 7 pur*as$ f ^! comm]cial collectors1 h5ce !y consi/ almo/ entirely ( p]fectly pres]v$ fi%1 z poorly pres]v$ specim5s w\ld be disc>d$ by ! collectors z ( no monet>y value4 ,! result has be5 t mo/ p1 includ+ ,bradley1 7 misl$ into believ+ all ( ! fi% 9 ! v>v$ s$im5ts ( ! qu>ry 7 p]fectly pres]v$4 ,z ne>ly z c be det]m9$1 ! fir/ attempt to sy/ematically collect & /udy ?is conc5tration ( fi% 0 t by paleontologi/s f ! ,univ]sity ( ,wyom+ 7,mc,grew #aigd74 ,?is "w ?rew mu* new light on ! occurr5ce & made available mu* new data t p]mit new int]pretations4 ,%ales ( ! ,gre5 ,riv] ,=mation 9 g5]al h be5 describ$ by ,bradley 7#aica7 & he specifically m5tion$ ^? ( ! fi% lay] 9 ! ,fossil ,bas9 z foll[s3 8,plate #a %[s a ?9 section ( ! v>v$ m>l/one 9 ! small1 unnam$ ,gre5 ,riv] ,lake we/ ( ,gosiute ,lake1 :]e ! v>ves are bett] develop$4 ,ea* v>ve or annual deposit1 consi/s ( a lay] ( microgranul> c>bonates & a ?9n]1 d>k lay] ( organic matt]0 7,bradley #aidh3fde74 ,! ,x-ray diffraction analyses p]=m$ by ,john ,w>d ,smi? ( ! ,l>amie ,en]gy ,rese>* ,c5t] %[$ t ! %ales ( ! 8fi% lay]0 consi/ pr$om9antly ( calcite 7r\ghly #fj71 aragonite & dolomite 7approximately #bj71 & qu>tz 7up to #aj74 ,al?\gh fi% are num]\s ?r\gh\t ! ?ickness ( ?is 8fi% lay]10 !re are ?ree lam9ae t conta9 s _m fi% t x is almo/ c]ta9 t !y repres5t cata/rophic mass mortalities4 ,two are made up prim>ily ( ,priscac>a & "o consi/s almo/ exclusively ( ,knightia4 ,x-ray photos %[ t a r high p]c5tage ( ! fi% 9 ! %ales are n p]fectly pres]v$ b h und]gone v>y+ am\nts ( dis>ticulation4 ,!re appe>s to be an ord]ly sequ5ce ( /ages ( decomposition--f ess5tially p]fect articulation to total dis>ticulation4 ,dis>ticulation fir/ appe>s 9 ! mo/ ant]ior v]tebrae4 ,f !re x rapidly proce$s ant]iorly into ! head region & appe>s to d s po/]iorly at a sl[] rate4 ,9 _m specim5s ! head & ant]ior half ( ! body are completely dis>ticulat$1 :ile ! po/]ior "p ( ! body %[s no dis>ticulation :atev]4 ,x is assum$ t aft] ! dead fi% settl$ to ! bottom ( ! lake1 ext]nal ana]obic bact]ia f\nd access to ! 8inn>ds0 ( ! fi% via ! op]cul> op5+4 ,?is w\ld acc\nt = ! fir/ sign ( decomposition & dis>ticulation be+ j back ( ! head4 ,9 ! blocks ( %ale cov]$ by ,x-ray !re 7 #che fi%4 ,= conv5i5ce1 ^! 7 classifi$ into six gr\ps1 gr\p ,i %[+ no disc]nable dis>ticulation & gr\p ,,vi 7,fig4 #bi7 %[+ total dis>ticulation4 ,! numb] & p]c5tage ( fi% 9 ea* gr\p are z foll[s3 ,gr\p ,i #bbc fi% #eh ,gr\p ,,ii #ch fi% #aj ,gr\p ,,iii #ad fi% #d ,gr\p ,,iv #bg fi% #g ,gr\p ,v #bd fi% #f ,gr\p ,,vi #ei fi% #ae ,illu/ration3 ,fig4 #bi4 ,a p>tially dis>ticulat$ skeleton ( a l>ge ,priscac>a1 ,gr\p ,,iv4 ,because ( ! pr$om9ance ( completely articulat$ fi% ?r\gh\t ! qu>ry & ! fact t ! fi% involv$ 9 ! mass mortalities %[ no dis>ticulation1 x seems probable t "s connection might exi/ betwe5 ! dea? ( ! fi% & conditions ( ! lake bottom t w\ld cause _! p]fect pres]vation4 ,x w\ld seem t rapid burial might be ! mo/ obvi\s reason = excell5t pres]vation4 ,?us any factor or comb9ation ( factors t w\ld cause rapid precipitation ( c>bonates & also w\ld cause mortality ( fi% w\ld satisfy our requirem5ts4 ,"o obvi\s factor t c\ld1 at lea/ !oretically1 fulfill ^! requirem5ts w\ld be an annual bloom ( blue-gre5 algae t are kn[n to be toxic to fi% 7,prescott #aidh74 ,su* blooms usually occur dur+ ! w>me/ "p ( ! summ] :5 ,ca,c,o is lea/ soluble4 ,by extract+ ,,co f ! wat]1 ^! algae are kn[n to cause precipitation ( ,ca,c,o4 ,?us we h a possible cause = "s annual fi% kill & p]haps an occasional sup]bloom t w\ld br+ ab\t a cata/rophic mass mortality4 ,! highe/ mortality ( fi% !n might h occurr$ dur+ late summ] algal blooms & at ?is "t also w\ld occur ! mo/ rapid precipitation ( ,ca,c,o4 ,x is n kn[n h[ mu* deposition ( ,ca,c,o w\ld be requir$ to protect a fi% f dis>ticulation4 ,x may be t a v ?9 lay]1 especially if mix$ ) organic ooze1 might provide an effective seal to sl[ decomposition & prev5t dis>ticulation4 ,if suffici5t ,ca,c,o 0 precipitat$ & deposit$ to cov] ! fi% t di$ dur+ ?is p]iod1 "o might expect p]fect pres]vation4 ,su* fi% w\ld fit into gr\p ,i4 ,^? fi% t di$ j aft] ?is p]iod might lie expos$ on ! lake bottom = mo/ ( a ye> & be subject to dis>ticulation4 ,if little or no deposition took place dur+ ! re/ ( ! ye>1 fi% t di$ j aft] ! p]iod ( deposition %\ld be ! mo/ completely dis>ticulat$ & fit into gr\p ,,vi4 ,dur+ ! fall1 w9t]1 & spr+1 fi% t di$ ( attritional mortality w\ld be dis>ticulat$ accord+ to ! l5g? ( "t !y lay on ! bottom prior to ! next p]iod ( deposition4 ,if ! =ego+ is true1 "o %\ld be able to det]m9e ! approximate "t ( ye> fi% di$ by ! degree ( dis>ticulation4 ,"o might assume t blooms ( blue-gre5 algae & h5ce precipitation ( ,ca,c,o w\ld take place sometime dur+ ,augu/ &_/or ,septemb]4 ,?us we %\ld expect ! mo/ fi% & ^? mo/ p]fectly pres]v$ to h di$ dur+ ?is "t p]iod 7gr\p ,i74 ,^? fi% t di$ 9 ,octob] &_/or ,novemb] %\ld be ! mo/ completely dis>ticulat$ 7gr\p ,,vi71 & ^? t di$ 9 ,june or ,july %\ld %[ only a slight degree ( dis>ticulation 7gr\p ,,ii74 ,! di/ribution ( ! /ages ( dis>ticulation seems to fit almo/ exactly ! patt]n t "o w\ld expect if ?is int]pretation is correct4 ,gunt] 7#aidg7 has %[n t annual p]iods ( excess sal9ity 9 ,texas lagoons cause an annual increase 9 ! dea? ( fi% & occasionally a cata/rophic mass mortality4 ,because ,lake ,gosiute is kn[n to h be5 sal9e1 x might be assum$ t some:at simil> *emical conditions prevail$ 9 ! ,fossil ,lake4 ,x is n kn[n def9itely t ! two lakes 7 ev] connect$ b if !y 71 x 0 mo/ probably a n>r[ connection ne> ! s\!rn end ( ,fossil ,lake & probably a r tempor>y connection4 ,t a r long p]iod ( aridity occurr$ 9 ! g5]al region is demon/rat$ by v>i\s depositional features1 prim>y /ructures1 & salt deposition 9 ,gosiute ,lake 9 a "p ( ! ,gre5 ,riv] ,=mation4 ,^! deposits appe> to h settl$ d[n dur+ ,lo/cab9ian 7late to e>ly ,eoc5e7 times4 ,because ! ,wasat* ,=mation imm$iately und]ly+ ! ,fossil ,butte ,memb] ( ! ,gre5 ,riv] ,=mation 9 ! ,fossil ,syncl9e ,bas9 is ,lysitean 7mid to e>ly ,eoc5e71 x is probable t ! fi% deposits are ( ,lo/cab9ian age4 ,?us x may well be t ! long p]iod ( aridity occurr$ dur+ ! deposition ( ! fi% b$s4 ,:ile ! ,fossil ,lake probably nev] rea*$ ! high degree ( sal9ity pres5t 9 ,lake ,gosiute1 x 0 probably suffici5tly sal9e t p]iods ( excessive evaporation c\ld increase ! sal9ity en\gh to contribute to ! mortality ( fi% & occasionally cause a cata/rophic mass mortality su* z ^? describ$ by ,gunt]4 ,! pres5ce ( aragonite & dolomite 9 ! %ales sugge/s t at lea/ "s ( ! c>bonate deposition might well h be5 because ( excessive evaporation & high conc5trations ( c>bonates 7,smi? #aigd1 p]s4 comm474 ,at ! ,univ]sity ( ,wyom+1 an attempt is be+ made to int]pret scales ( fi% f ! qu>ries4 ,9 a numb] ( specim5s annuli c be obs]v$ & circuli c\nt$4 ,al?\gh removal ( scales = /udy is extremely difficult1 a numb] has be5 remov$ & photograph$ ) a scann+ electron microscope4 ,9 ,lake ,george1 ,florida1 black crappie develop annuli dur+ ,janu>y1 ,febru>y1 ,m>*1 & ,april 7,hui% #aied74 ,climatic conditions 9 nor? c5tral ,florida may be simil> to ^? t exi/$ 9 we/]n ,wyom+ dur+ ! e>ly ,eoc5e4 ,?us annuli may h develop$ at ! same "t ( ye>4 ,by c\nt+ ! numb] ( circuli betwe5 ! la/ annulus & ! edge ( ! scale1 x %\ld be possible to det]m9e ! approximate "t ( dea? ( a fossil fi%4 ,if ?is %\ld correlate ) ! degree ( dis>ticulation1 a *eck on ?is int]pretation %\ld be possible4 ,suffici5t data are n yet available1 h[ev]1 = ! results to be conclusive4 ,x is n int5d$ to sugge/ t ! conditions outl9$ above c\ld acc\nt = all ( ! fi% conc5trations 9 ! ,gre5 ,riv] ,%ales4 ,9 c]ta9 %ales 9 ! ,gre5 ,riv] ,bas91 = example1 ! conc5trations ( ,knightia 9 nonv>v$ %ales appe> to h be5 deposit$ 9 q %all[ wat]4 ,^! fi% are extremely well pres]v$ b 7 obvi\sly laid d[n "u conditions q diff]5t f ^? at ,fossil ,butte4 ,mu* /udy ( ^! occurr5ces w be necess>y be=e int]pretations are possible4 ,! /ory1 z told "h1 %\ld make x cle> t ! e>? is ev]-*ang+4 ,:at 0 once a beautiful1 deep lake 9 an area ( lu% tropical =e/s is n[ a dry1 sagebru% des]t4 ,:at 0 once an area 9 :i* s$im5ts 7 accumulat+ is n[ an area ( erosion1 occasion$ by a broad uplift ( ! region ne> ! end ( ,t]ti>y "t4 ,x is hop$ t ?is brief /ory ( ! geologic hi/ory ( ,fossil ,butte ,national ,monum5t w give ! read] "s appreciation ( ! geologic complexity n only ( ! monum5t itself b ( ! surr\nd+ area z well4 ,c]ta9ly su* k w add to ! enjoym5t ( a visit to ! monum5t4 ,x may seem t geologi/s h all ( ! answ]s4 ,?is1 h[ev]1 is n s4 ,int]pretations are made on ! basis ( available evid5ce4 ,ea* "t a geologi/ /udies an area m geologic data & m evid5ce become available & our int]pretations become a little m accurate4 ,x w be _m ye>s be=e all details ( ?is fasc9at+ hi/ory w be kn[n4 ,,gloss>y ,,ana]obic4 ,usually 9 ref]5ce to organisms t c live )\t oxyg54 ,,angul> ,,uncon=mity4 ,two rock lay]s :i* are n p>allel2 ! und]ly+ old] lay] dips at a diff]5t angle 7usually /eep]7 ?an ! y\ng] top /rata4 ,,annuli4 ,m>ks on fi% scales produc$ by p]iods 7usually w9t]7 ( nongr[?4 ,,anticl9e4 ,a fold 9 /ratifi$ rock ) ! /rata slop+ d[nw>d 9 opposite directions f ! fold cre/4 ,,aragonite4 ,a c>bonate m9]al ) specific *>act]i/ics4 ,,au?ig5ic4 ,a m9]al 7su* z qu>tz or feldsp>7 :i* is =m$ aft] ! deposition ( a s$im5t>y lay] 9 :i* x occurs4 ,,b5tonite4 ,a light-color$1 s(t1 por\s rock =m$ f ! m9ute clay cry/als ( erod$ volcanic a%4 ,x has ! *>act]i/ic ( swell+ :5 wet 7wat] absorption7 & contract+ :5 dry4 ,,bracki%4 ,a condition 9 a body ( wat] 9 :i* ! sal9ity 7salt level7 is bel[ t ( sea wat]1 b high] ?an t ( fre% wat]4 ,,c>bonace\s4 ,rock or s$im5t :i* conta9s c>bon or alt]$ organic mat]ial su* z coal4 ,,*]ty4 ,conta9+ *]t3 a dull-color$1 fl9t-l qu>tz (t5 f\nd 9 lime/one4 ,,circuli4 ,ridges on fi% scales produc$ dur+ gr[? ( ! scales4 ,,cla/4 ,rock fragm5ts :i* are ! result ( wea!r+ ( a l>g] rock mass4 ,,cla/ic4 ,rocks t consi/ ( p>ticles d]iv$ f pre-exi/+ rocks or m9]als4 ,,clay/one4 ,an indurat$ clay )\t ! lam9ation or fissility ( %ale4 ,,conglom]ate4 ,a co>se-gra9$ s$im5t>y rock compos$ ( fragm5ts l>g] ?an #b mm 9 diamet] 9 a f9e-gra9$ matrix4 ,,cross-,,b$d+4 ,an int]nal /ructure 9 s$im5t>y rock 9 :i* ! upp] s$im5t>y lay] runs across ! gra9 ( ! ma9 b$2 x is caus$ by *ang+ curr5ts deposit+ s$im5t across ! gra9 ( ! orig9al deposits4 ,,diamictite4 ,a s$im5t>y rock conta9+ a wide range ( p>ticle sizes4 ,,dip4 ,! d[nw>d incl9ation ( a rock lay]2 ! v]tical angle is det]m9$ by its relation%ip to a horizontal plane4 ,,dolomitic4 ,conta9+ a measurable am\nt ( ! m9]al dolomite2 a m9]al consi/+ ma9ly ( magnesium c>bonate & calcium c>bonate4 ,,facies4 ,lat]al v>iations 9 ! appe>ance or composition ( a rock lay]4 ,! v>iations c be li?ologic or paleontologic4 ,,fault4 ,a fracture 9 ! e>?'s cru/ along :i* displacem5t 7movem5t7 has occurr$4 ,,fluvial4 ,p]ta9+ to a riv] or riv]s4 ,fluvial s$im5ts are ^? transport$ & deposit$ by /ream action4 ,,=mation4 ,a rock lay] t is mappable2 has a di/9ctive li?ology or s]ies ( li?ologies4 ,a mappable sequ5ce ( uni=m or uni=mly v>y+ rocks4 ,,ga/ropodal4 ,a rock conta9+ an abundance ( ga/ropods4 ,,hogback4 ,a long1 n>r[1 %>p-cre/$ ridge =m$ by ! outcropp+ edges ( /eeply incl9$ resi/ant rocks4 ,,igne\s ,,rocks4 ,a rock or m9]al t has solidifi$ f molt5 or p>tly molt5 mat]ial4 ,,intrusive4 ,igne\s rock =m$ by ! =c+ ( molt5 mat]ial into a pre-exi/+ rock4 ,,iron/one4 ,a rock compos$ ( v>i\s iron m9]als t accumulat$ dur+ or %ortly aft] deposition ( ! enclos+ s$im5ts4 ,,lacu/r9e4 ,p]ta9+ to1 produc$ by1 or =m$ 9 a lake or lakes4 ,,lat]itic4 ,conta9+ lat]ite3 a r$1 por\s mat]ial usually develop$ 9 a tropical to temp]ate climate4 ,x is a residual or end-product ( wea!r+4 ,,lignite4 ,a br[ni%-black coal t is int]m$iate 9 coalification betwe5 peat & subbitum9\s coal4 ,,li?ology4 ,! sci5tific /udy ( rocks3 composition1 texture1 color1 orig91 etc4 ,,magnetite4 ,a black1 opaque m9]al t is /rongly magnetic4 ,,m>l/one4 ,an impure lime/one4 ,,metamorphic4 ,rocks ^: /ructure has be5 *ang$ by pressure1 heat1 *emical reaction1 etc41 su* z lime/one into m>ble4 ,,mud/one4 ,an indurat$ mud )\t ! lam9ation or fissility ( %ale4 ,,op]cul> ,,op5+4 ,! gill op5+ ( fi%4 ,,o/racodal4 ,a rock1 usually a lime/one1 t conta9s an abundance ( ! small cru/acean1 o/racods4 ,,ov]?ru/4 ,a l[-angle ?ru/ fault ( l>ge scale1 usually measur$ 9 miles4 ,,paleolimnology4 ,! /udy ( anci5t lakes4 ,,pap] ,,%ale4 ,a =m ( f9ely lam9at$ %ale t wea!rs into extremely ?91 curl$ flakes4 ,,phosphatic4 ,conta9+ phosphates4 ,,phytoplankton4 ,float+ microscopic plant life t occurs abundantly 9 lakes & oceans4 ,,platy4 ,rocks 7s&/one or lime/one7 :i* sep>ate into small slabs4 ,,porcellanite4 ,a d5se *]ty rock resembl+ porcela94 ,,pudd+/one4 ,a conglom]ate consi/+ ( well-r\nd$ pebbles & cobbles sp>sely pack$ 9 a f9e-gra9$ matrix4 ,,silt/one4 ,an indurat$ silt )\t ! lam9ation or fissility ( %ale4 ,,/rata4 ,rock lay]s ( di/9ct composition & orig94 ,,syncl9e4 ,a fold 9 /ratifi$ rock 9 :i* ! /rata slope up f ! axis ( ! fold =m+ a v oppos$ to anticl9e4 ,,taphonomy4 ,! bran* ( paleoecology :i* deals ) ! *ange f liv+ animals to fossils4 ,,tectonic4 ,! =ces :i* result 9 /ructural *anges 9 ! e>?'s cru/4 ,,?ru/ ,,fault4 ,a fault 9 :i* an upp] segm5t ( rock 7hang+ wall7 moves upw>d at a l[ angle 7less ?an #de7 relative to a l[] segm5t 7footwall74 ,,tongue4 ,a rock unit t w$ges into1 b disappe>s )91 ano!r rock unit4 ,,tufface\s4 ,s$im5t t conta9s up to #ej volcanic a% or du/4 ,,uncon=mity4 ,a sub/antial break or gap 9 ! geologic or /ratigraphic record4 ,,ungulates4 ,hoov$ mammals4 ,,v>ve4 ,a set ( rock lam9ae 9 :i* diff]5t types ( s$im5t 7 deposit$ 9 ! w9t] & 9 ! summ]4 ,?us a c\plet ( ea* s$im5t type w\ld repres5t ! deposition ( "o ye>4 ,,well ,,sort$4 ,a rock 9 :i* ne>ly all ( ! s$im5t p>ticles are ( "o gra9 size4 ,,zooplankton4 ,float+ microscopic animal life t occurs abundantly 9 lakes & oceans4 ,,ref]5ces ,,black/one1 ,d4 ,l41 ,jr4 #aiga4 ,travel]'s guide to ! geology ( ,wyom+4 ,wyo4 ,geol4 ,surv4 ,bull4 #ee3a-ij4 ,,bradley1 ,w4 ,h4 #aibf4 ,%ore phases ( ! ,gre5 ,riv] ,=mation 9 nor!rn ,sweetwat] ,c\nty1 ,wyom+4 ,pages #aba-aca 9 ,u4,s4 ,geol4 ,surv4 ,pr(4 ,pap4 #adj-;,d4 ----4 #aibi4 ,! v>ves & climate ( ! ,gre5 ,riv] ,epo*4 ,pages #hg-aaj 9 ,u4,s4 ,geol4 ,surv4 ,pr(4 ,pap4 #aeh-;,e4 ----4 #aica4 ,orig9 & micr(ossils ( ! oil %ale ( ! ,gre5 ,riv] ,=mation ( ,colorado & ,utah4 ,pages #a-eh 9 ,u4,s4 ,geol4 ,surv4 ,pr(4 pap4 #afh4 ----4 #aidh4 ,limnology & ! ,eoc5e lakes ( ! ,rocky ,m\nta9 region4 ,geol4 ,soc4 ,am4 ,bull4 #ei3fce-fdh4 ----4 #aifc4 ,paleolimnology4 ,pages #fba-feb 9 ,d4 ,g4 ,frey1 ed4 ,limnology 9 ,nor? ,am]ica4 ,univ4 ( ,wiscons9 ,press4 ----4 #aifd;a4 ,geology ( ! ,gre5 ,riv] ,=mation & associat$ ,eoc5e rocks 9 s\?we/]n ,wyom+ & adjac5t p>ts ( ,colorado & ,utah4 ,u4,s4 ,geol4 ,surv4 ,pr(4 ,pap4 #dfi-;,a4 ----4 #aifd;b4 ,aquatic fungi f ! ,gre5 ,riv] ,=mation ( ,wyom+4 ,am4 ,j4 ,sci4 #bfb3dac-daf4 ----4 #aiff4 ,tropical lakes1 copropel1 & oil %ale4 ,geol4 ,soc4 ,am4 ,bull4 #gg3accc-acch4 ,,brodkorb1 ,p4 #aigj4 ,an ,eoc5e puffbird f ,wyom+4 ,contr4 ,geol4 7,univ4 ( ,wyo47 #i7a73ac-ae4 ,,br[n1 ,r4 ,w4 #aibi4 ,additions to ! flora ( ! ,gre5 ,riv] ,=mation4 ,pages #de-gg 9 ,u4,s4 ,geol4 ,surv4 ,pr(4 ,pap4 #ahe-;,c4 ----4 #aicd4 ,! recognizable species ( ! ,gre5 ,riv] ,flora4 ,pages #de-gg 9 ,u4,s4 ,geol4 ,surv4 ,pr(4 ,pap4 #ahe-;,c4 ,,cockrell1 ,t4 ,d4 ,a4 #aibj4 ,eoc5e insects f ! ,rocky ,m\nta9s4 ,u4,s4 ,natl4 ,mus4 ,proc4 #eg3bcc-bfj4 ,,cope1 ,e4 ,d4 #ahgg4 ,a contribution to ! k ( ! ic?yological fauna ( ! ,gre5 ,riv] ,%ales4 ,u4,s4 ,geol4 ,geog4 ,surv4 ,t]ritories ,bull4 #c7d73hjg-hai4 ----4 #ahgh4 ,descriptions ( fi%es f ! ,cretace\s & ,t]ti>y deposits we/ ( ! ,mississippi ,riv]4 ,u4,s4 ,geol4 ,geog4 ,surv4 ,t]ritories ,bull4 #d7a73fg-gg4 ,,cope4 #ahhd4 ,! v]tebrata ( ! ,t]ti>y ,=mations ( ! ,we/4 ,book #a1 ,rep4 ,geol4 ,surv4 ( ! ,t]ritories #c3a-ajji4 ,,e>dley1 ,a4 ,j4 #aiei4 ,review ( ! geology ( nor!a/ ,utah & s\?we/ ,wyom+4 ,pages #aff-aga 9 ,int]m\nta9 ,assoc4 ( ,pet4 ,geol4 ,guidebook1 #aj? ,ann4 ,field ,conf41 ,wasat* & ,u9ta ,m\nta9s ,transition ,area4 ,,eug/]1 ,h4 ,p41 & ,r4 ,c4 ,,surdam4 #aigc4 ,depositional environm5t ( ! ,gre5 ,riv] ,=mation ( ,wyom+1 a prelim9>y report4 ,geol4 ,soc4 ,am4 ,bull4 #hd3aaae-aabj4 ,,gaz91 ,c4 ,l4 #aief4 ,! occurr5ce ( ,paleoc5e mammalian rema9s 9 ! ,fossil ,bas9 ( s\?we/]n ,wyom+4 ,j4 ,paleontol4 #ci7c73gjg-gag4 ----4 #aiei4 ,paleontological exploration & dat+ ( ! ,e>ly ,t]ti>y deposits 9 bas9s adjac5t to ! ,u9ta ,m\nta9s4 ,pages #aca-ach 9 ,int]m\nta9 ,assoc4 ( ,petrol4 ,geol4 ,guidebook1 #aj? ,ann4 ,field ,conf41 ,wasat* & ,u9ta ,m\nta9s transitional area4 ----4 #aifi4 ,a new occurr5ce ( ,paleoc5e mammals 9 ! ,evan/on ,=mation ( s\?we/]n ,wyom+4 ,smi?son4 ,contr4 ,paleobiol4 no4 #b1 #ag p4 ,,gunt]1 ,g4 #aidg4 ,cata/rophism 9 ! sea & its paleontological significance1 ) special ref]5ce to ! ,gulf ( ,mexico4 ,am4 ,j4 ,sci4 #bde7aa73ffi-fgf4 ,,hayd51 ,f4 ,v4 #ahfi4 ,prelim9>y field report ( ! ,u4,s4 ,geological ,survey ( ,colorado & ,new ,mexico 7#crd ,ann474 #add p4 ----4 #ahga4 ,prelim9>y report ( ! ,u4,s4 ,geological ,survey ( ,wyom+ & portions ( contigu\s t]ritories4 #eaa p4 ,,hui%1 ,t4 #aied4 ,life hi/ory ( ! ,black ,crappie ( ,lake ,george1 ,florida4 ,trans4 ,am4 ,fi%4 ,soc4 #hc3agf-aic4 ,,jeps51 ,g4 ,l4 #aiff4 ,e>ly ,eoc5e bat f ,wyom+4 ,sci5ce #aed7cged73 #accc-acci4 ,,knight1 ,s4 ,h4 #aiee4 ,review ( ! e>ly geological explorations ( ! ,gre5 ,riv] ,bas9 area1 #ahab-ahgi4 ,pages #aj-ag 9 ,wyo4 ,geol4 ,assn4 #aj? ,ann4 ,field ,conf4 ,guidebook 7,gre5 ,riv] ,bas974 ,,leidy1 ,j4 #ahef4 ,notice ( "s rema9s ( fi%es discov]$ by ,dr4 ,john ,e4 ,evans4 ,acad4 ,nat4 ,sci41 ,phila4 ,proc4 #h3bef-beg4 ,,lesqu]eux1 ,l4 #ahhc4 ,contributions ( ! fossil flora ( ! we/]n t]ritories4 ,"p #c 9 ,f4 ,v4 ,hayd51 ,! ,cretace\s & ,t]ti>y floras4 ,u4,s4 ,geol4 ,survey ( ! ,t]ritories1 ,rept4 #h1 #bhc p4 ,mc,g,r,e,w1 ,p4 ,o4 #aigd4 ,taphonomy ( ,eoc5e fi% f ,fossil ,bas91 ,wyom+4 ,fieldiana #cc 79 press74 ,,nelson1 ,m4 ,e4 #aigc4 ,age & /ratigraphic relations ( ! ,f[kes ,=mation1 ,eoc5e1 ( s\?we/]n ,wyom+ & nor!a/]n ,utah4 ,contr4 ,geol4 7,univ4 ( ,wyom+7 #ab7a73bg-ca4 ,,oriel1 ,s4 ,s41 & ,j4 ,i4 ,,tracey4 #aigj ,upp]mo/ ,cretace\s & ,t]ti>y /ratigraphy ( ,fossil ,bas91 s\?we/ ,wyom+4 ,u4,s4 ,geol4 ,surv4 ,pr(4 ,pap4 #fce4 #ec p4 ,,peale1 ,a4 ,c4 #ahgi4 ,report on ! geology ( ! ,gre5 ,riv] di/rict4 ,pages #eji-fdf 9 ,f4 ,v4 ,hayd54 #aa? ,ann4 ,rept41 ,u4,s4 ,geol4 ,surv4 ( ! ,t]ritories4 ,,prescott1 ,g4 ,w4 #aidh4 ,objectionable algae ) ref]5ce to ! kill+ ( fi% & o!r animals4 ,hydrobiologia #a3a-ac4 ,,rubey1 ,w4 ,w41 ,j4 ,i4 ,,tracey1 & ,s4 ,s4 ,,oriel4 #aifh;a4 ,prelim9>y geologic map ( ! ,kemm]] quadrangle1 ,l9coln ,c\nty1 ,wyom+4 ,u4,s4 ,geol4 ,surv41 op5 file map4 ----4 #aifh;b4 ,prelim9>y map ( ! ,sage quadrangle1 ,l9coln ,c\nty1 ,wyom+4 ,u4,s4 ,geol4 ,surv41 op5 file map4 ,,s*aeff]1 ,b41 & ,m4 ,,mangus4 #aife4 ,fossil lakes f ! ,eoc5e4 ,am4 ,mus4 ,nat4 ,hi/4 #gd7d73aa-ba4 ,,s*ultz1 ,a4 ,r4 #aiad4 ,geology & geography ( a portion ( ,l9coln ,c\nty1 ,wyom+4 ,pages #a-ada 9,u4,s4 ,geol4 ,surv4 ,bull4 #edc4 ,,scudd]1 ,s4 ,h4 #ahij4 ,! ,t]ti>y insects ( ,nor? ,am]ica4 ,rept4 #ac 9 ,f4 ,v4 ,hayd54 ,u4,s4 ,geol4 ,geog4 ,surv4 ( ! ,t]ritories4 #gcd p4 ,,tracey1 ,j4 ,i41 & ,s4 ,s4 ,,oriel4 #aiei4 ,upp]mo/ ,cretace\s & ,l[] ,t]ti>y rocks ( ! ,fossil ,bas94 ,pages #abf-acj 9 ,int]m\nta9 ,assoc4 ,petrol4 ,geol4 ,guidebook4 #aj? ,annual ,field ,conf41 ,wasat* & ,u9ta ,m\nta9s transitional area4 ----1 & ,w4 ,w4 ,,rubey4 #aifa4 ,diamicitite facies 9 ! ,wasat* ,=mation 9 ! ,fossil ,bas91 s\?we/]n ,wyom+4 ,pages #adi-aej 9 ,%ort ,pap4 9 ! ,geol4 & ,hydrol4 ,sci41 ,u4,s4 ,geol4 ,surv4 ,pr(4 ,pap4 #dbd;b4 ,,van ,,h\t51 ,f4 ,b4 #aidh4 ,orig9 ( r$-b&$ e>ly ,c5ozoic deposits 9 ! ,rocky ,m\nta9 region4 ,pages #bjhc-babf 9 ,am4 ,assoc4 ,petrol4 ,geol4 ,bull4 #cb7aa74 ,u4,s4 ,,dep>tm5t ,,( ,,! ,,int]ior4 #aifd4 ,propos$ ,fossil ,butte ,national ,monum5t4 ,national ,p>k ,s]vice ,midwe/ ,region1 ,omaha1 ,neb4 ,,veat*1 ,a4 ,c4 #aigj4 ,geography & geology ( a portion ( s\?we/]n ,wyom+ ) special ref]5ce to coal & oil4 ,u4,s4 ,geol4 ,surv4 ,pr(4 ,pap4 #ef4 #agh p4 ,,bibliography ,,b]ry1 ,e4 ,w4 #aibe4 ,flora & ecology ( ! s-call$ ,bridg] ,b$s ( ! ,w9d ,riv] ,bas91 ,wyom+4 ,pan-,am4 ,geol4 #dd3ceg-cfh4 ,,bradley1 ,w4 ,h4 #aiei4 ,revision ( /ratigraphic nom5clature ( ! ,gre5 ,riv] ,=mation ( ,wyom+4 ,am4 ,assoc4 ,petrol4 ,geol4 ,bull4 #dc3ajgb-ajge4 ----4 #aigc4 ,oil %ale =m$ 9 des]t environm5t1 ,gre5 ,riv] ,=mation1 ,wyom+4 ,geol4 ,soc4 ,am4 ,bull4 #hd3aaba-aabd4 ,,bradley1 ,w4 ,h41 & ,h4 ,p4 ,,eug/]4 #aifi4 ,geo*emi/ry & paleolimnology ( ! ,trona deposits & associat$ au?ig5ic m9]als ( ! ,gre5 ,riv] ,=mation ( ,wyom+4 ,u4,s4 ,geol4 ,surv4 ,pr(4 ,pap4 #dif-;,b1 #gj p4 ,,brong]sma-,,s&]s1 ,m4 #aieg4 ,mass mortality 9 ! sea4 ,pages #ida-ajaj 9 ,treatise on m>9e ecology & paleoecology4 ,g4,s4,a4 ,memoir #fg4 ,,gaz91 ,c4 ,l4 #aieb4 ,! l[] ,eoc5e ,knight ,=mation ( ,wyom+ & its mammalian faunas4 ,smi?son4 ,misc4 ,coll4 #aag7ah73 #a-hb4 ----4 #aief;a4 ,! upp] ,paleoc5e mammalia f ! ,almy ,=mation 9 we/]n ,wyom+4 ,smi?son4 ,misc4 ,coll4 #aca7g73 #a-ah4 ----4 #aifb4 ,a fur!r /udy ( ! l[] ,eoc5e mammalian faunas ( s\?we/]n ,wyom+4 ,smi?son4 ,misc4 ,coll4 #add7a73a-ih4 ,,g>y1 ,m41 ,r4 ,mc,a,f,e,e1 ,jr41 & ,c4 ,l4 ,,wolf 7eds474 #aigb4 ,gloss>y ( ,geology4 ,am]4 ,geol4 ,in/41 ,wa%+ton1 ,d4,c4 #heg p4 ,,hesse1 ,c4 ,j4 #aici4 ,fossil fi% localities 9 ! ,gre5 ,riv] ,eoc5e ( ,wyom+4 ,sci4 ,mon?ly #dh3adg-aea4 ,,hut*9son1 ,g4 ,e4 #aieg4 ,a ,treatise on ,limnology1 vol4 #a 7,geography1 ,physics1 ,*emi/ry74 ,john ,wiley & ,sons1 ,new ,york4 #ajae p4 ,,oriel1 ,s4 ,s4 #aifa4 ,tongues ( ! ,wasat* & ,gre5 ,riv] ,=mation1 ,=t ,hill area1 ,wyom+4 ,pages #aea-aeb 9 ,%ort ,pap4 9 ! ,geol4 ,hydrol4 ,sci41 ,u4,s4 ,geol4 ,surv4 ,pr(4 ,pap4 #dbd;b4 ----1 ,c4 ,l4 ,,gaz91 & ,j4 ,i4 ,,tracey4 #aifb4 ,eoc5e age ( ! ,almy ,=mation1 ,wyom+1 9 its type area4 ,am4 ,assoc4 ,petrol4 ,geol4 ,bull4 #df7aj73 #aicf-aicg4 ,,rom]1 ,a4 ,s4 #aiff4 ,v]tebrate paleontology1 #crd ed4 ,univ4 ,*icago ,press4 #dfh p4 ,,rubey1 ,w4 ,w41 ,s4 ,s4 ,,oriel1 & ,j4 ,i4 ,,tracey4 #aifa4 ,age ( ! ,evan/on ,=mation1 we/]n ,wyom+4 ,pages #aec-aed 9 ,%ort ,pap4 9 ! ,geol4 & ,hydrol4 ,sci41 ,u4,s4 ,geol4 ,surv4 ,pr(4 ,pap4 #dbd;b4 ,,se>s1 ,j4 ,d41 & ,w4 ,h4 ,,bradley4 #aibd4 ,relations ( ! ,wasat* & ,gre5 ,riv] =mations 9 nor?we/ ,colorado & s\!rn ,wyom+ ) notes on oil %ale 9 ! ,gre5 ,riv] ,=mation4 ,pages #ic-ajg 9 ,u4,s4 ,geol4 ,surv4 ,pr(4 ,pap4 #acb;f4 ,,?orpe1 ,m4 ,r4 #aich4 ,wyom+ ,eoc5e fi%es 9 ! ,m>% collection4 ,am4 ,j4 ,sci4 #cf3bgi-bie4 ,,ackn[l$gm5ts ,?is report1 :i* 0 prep>$ "u ,national ,p>k ,s]vice ,contract ,,cx #fjjj-c-jjgf1 leans heavily on ! publications ( ^? _m p :o h /udi$ v>i\s geologic aspects ( ! ,fossil ,bas94 ,we w\ld l to cite p>ticul>ly ,doctors ,/ev5 ,oriel & ,jo%ua ,tracy ( ! ,unit$ ,/ates ,geological ,survey1 ^: /udies h cl>ifi$ ! /ratigraphic relation%ips ( ! s$im5ts involv$4 ,dr4 ,d4 ,l4 ,black/one1 ,jr41 ( ! ,univ]sity ( ,wyom+ suppli$ in=mation f 8 yet unpubli%$ int]pretations ( ! complicat$ /ructure ( ! ,idaho-,wyom+ ?ru/ belt4 ,mr4 ,tom ,b[n help$ ) ! /ructural "p ( ! report & critically review$ o!r p>ts4 ,! draft+1 except = ,figs4 #c & #i1 0 done by ,mr4 ,evan ,gr\tage4 ,mrs4 ,ela9e ,h]tzfeldt1 secret>y = ! ,dep>tm5t ( ,geology1 aid$ greatly 9 prep>+ ?is manuscript4 ,paul ,o4 ,mc,grew ,mi*ael ,casilliano ,illu/ration3 ,,dep>tm5t ,,( ,,! ,,int]ior ,,m>* #c #ahdi2 ,,national ,,p>k ,,s]vice ,transcrib]'s ,notes --,sil5tly correct$ a few typos1 includ+ inconsi/5t spell+ ( 8,lo/cab9ian04 --,reta9$ publication in=mation f ! pr9t$ edition3 ?is e,book is public-doma9 9 ! c\ntry ( publication4 --,9 ! text v]sions only1 text 9 italics is delimit$ by und]scores4