,,bureau ,,( ,,economic ,,geology ,! ,univ]sity ( ,texas at ,au/9 ,pet] ,t4 ,flawn1 ,director ,guidebook #h ,! ,geologic ,/ory ( ,palo ,duro ,canyon ,by ,william ,h4 ,mat!ws ,,iii ,illu/ration3 ,,! ,,univ]sity ,,( ,,texas ,,at ,,au/9 ,augu/ #aifi ,second ,pr9t+ ,augu/ #aihc ,cont5ts ,introduction #a ,ackn[l$gm5ts #b ,p>k hi/ory #c ,anci5t man 9 ,palo ,duro ,canyon #c ,indians ( ! ,pla9s #c ,adv5t ( ! ,:ite ,man #c ,regional sett+ #h ,! geologic /ory #aj ,! canyon's rocks & m9]als #aj ,unravel+ e>? hi/ory #aj ,! geologic column & geologic "t scale #ab ,geologic =mations expos$ 9 ,palo ,duro ,canyon #af ,qu>t]ma/] ,=mation #ag ,tecovas ,=mation #ai ,trujillo ,=mation #bb ,ogallala ,=mation #bc ,rocks ( ! ,plei/oc5e #bh ,h[ ! canyon 0 c>v$ #bi ,! geologic "w ( runn+ wat] #bi ,wea!r+ & gravity add ! f9al t\* #cj ,wea!r+ #cj ,mass-wa/+ #ca ,diff]5tial erosion #ca ,:at to d & see at ,palo ,duro ,canyon ,/ate ,p>k #cc ,p>k ,entrance #cc ,coronado ,lodge & ,obs]vation ,po9t #cc ,! ,sc5ic ,drive #cc ,pione] ,amphi!atre #cc ,sad ,monkey ,tra9 ,ride #ce ,triassic ,peak #ce ,spani% ,skirts #cg ,cat>9a ,cave #cg ,santana's ,face #cg ,! ,sky ,ride #cg ,! ,fir/ ,wat] ,cross+ #ci ,colonel ,*>les ,goodnight's ,dug\t #ci ,! ,ligh?\se #ci ,capitol ,peak #dj ,=tress ,cliff #dj ,! ,rock ,g>d5 #dj ,! ,devil's ,slide #dj ,! ,turn>\nd #da ,hik+ #dc ,horseback rid+ #dc ,camp+ & picnick+ #dc ,photography #dc ,panh&le-,pla9s ,hi/orical ,museum #de ,select$ ref]5ces #dg ,gloss>y #dh ,index #ej ,illu/rations ,figures-- ,page #a4 ,a]ial ,view ( ,palo ,duro ,canyon ,frontispiece #b4 ,place map ( ,palo ,duro ,canyon #d-e #c4 ,indian c>v+ on s&/one b\ld] #f #d4 ,w> dress ( ,coman*e ,*ief ,quanah ,p>k] #g #e4 ,g5]aliz$ geologic map ( ! ,texas ,panh&le #i #f4 ,geologic "t scale #aa #g4 ,g5]aliz$ geologic map ( ,palo ,duro ,canyon ,/ate ,p>k #ad-ae #h4 ,jo9ts & gypsum ve9s 9 ,qu>t]ma/] ,=mation #ag #i4 ,syncl9e 9 ,qu>t]ma/] r$ b$s #ah #aj4 ,r$uction halos 9 ,qu>t]ma/] %ale #bj #aa4 ,cross-b$d$ b\ld] ( ,trujillo s&/one #bj #ab4 ,panoramic view ( canyon %[+ major rock units expos$ 9 canyon #ba #ac4 ,phytosaur skull #bb #ad4 ,skeleton ( ,buettn]ia #bd #ae4 ,mort> hole made by ,indians #be #af4 ,rock p$e/al ne> ! ,ligh?\se #be #ag4 ,outcrop ( ,ogallala cali*e #bf #ah4 ,life-siz$ model ( %ovel-jaw$ ma/odon #bg #ai4 ,fossiliz$ c>apaces ( ,plioc5e tortoises #bg #bj4 ,talus slopes & 8hoodoo0 on ,capitol ,peak #ca #ba4 ,entrance to ,palo ,duro ,canyon ,/ate ,p>k #cd #bb4 ,coronado ,lodge #cd #bc4 ,pione] ,amphi!atre #ce #bd4 ,tra9 on ,sad ,monkey ,railroad track #cf #be4 ,s\? face ( ,triassic ,peak #cf #bf4 ,spani% ,skirts #cg #bg4 ,cat>9a ,cave #ch #bh4 ,santana's ,face #ch #bi4 ,picnic area at fir/ wat] cross+ #ci #cj4 ,colonel ,*>les ,goodnight's ,dug\t #dj #ca4 ,! ,ligh?\se #da #cb4 ,capitol ,peak #db #cc4 ,=tress ,cliff #db #cd4 ,! ,rock ,g>d5 #dc #ce4 ,! ,devil's ,slide #dd #cf4 ,campsite 9 s\? end ( p>k #dd #cg4 ,entrance to ,panh&le-,pla9s ,hi/orical ,museum #de ,illu/ration3 ,fig4 #a4 ,a]ial view ( ,palo ,duro ,canyon %[+ location ( major po9ts ( int]e/3 7#a7 ,coronado ,lodge2 7#b7 ,triassic ,peak2 7#c7 ,timb] ,mesa2 7#d7 ,capitol ,peak2 7#e7 ,=tress ,cliff2 7#f7 ,prairie ,dog ,t[n ,=k ( ,r$ ,riv]2 7#g7 ,! ,turn>\nd 7t]m9ation ( ,p>k ,road #e74 7,c\rtesy ( ,*>les ,a4 ,wolf92 photograph by ,w4 ,a4 ,he/]47 ,! ,geologic ,/ory ( ,palo ,duro ,canyon ,william ,h4 ,ma!ws ,,iii#a ,,introduction ,l ! e>ly ,spani% explor]s :o fir/ saw ,palo ,duro ,canyon1 today's visitor is likely to view ! impressive canyon ) surprise & awe4 ,?is great depression--x is m ?an #b miles wide & z mu* z #hjj feet deep )9 p>k b\nd>ies--conta9s a fasc9at+ assortm5t ( multicolor$ geologic =mations & erosion-produc$ rock sculptures ( _m %apes1 colors1 & size4 ,! geographic sett+ ( ! canyon fur!r height5s its impact on ! visitor1 = x is surr\nd$ by ! level1 virtually treeless pla9s ( ! ,texas ,panh&le4 7,see upp] backgr\nd area 9 fig4 #a1 frontispiece74 ,x is n surpris+ t ?is sc5ic area has be5 set aside z a ,/ate p>k1 = ,palo ,duro ,canyon has long be5 ( int]e/ to man4 ,fir/1 z ! hunt+ gr\nds ( prehi/oric ,indians :o /alk$ ! n[-ext9ct ,ice ,age mammo?s & bison t roam$ ! valley floor4 ,lat]1 ! canyon 0 frequ5t$ by ! ,coman*es1 ,apa*es1 ,ki[as1 & o!r ,indians ( hi/oric "t4 ,^! tribes1 l ^? be=e !m1 f\nd bo? food & refuge )9 ! canyon4 ,h[ev]1 x 0 n until #ahgf t ,palo ,duro ,canyon 0 inhabit$ by ! :ite man4 ,x 0 dur+ ?is ye> t pione] cattleman ,*>les ,goodnight h]d$ "s #a1fjj head ( cattle into ! canyon & e/abli%$ a camp !re 7p4 #f74 ,today's visitor to ,palo ,duro ,canyon c re-live "s ( ! fasc9at+ hi/ory ( ?is int]e/+ area4 ,"o c /ill see a replica ( ,colonel ,goodnight's primitive dug\t1 foll[ ! fa9t trace ( ! ,coman*e ,trail1 or p]haps f9d ! fossil bones ( prehi/oric creatures t liv$ hundr$s ( ?\s&s--ev5 millions--( ye>s ago4 ,b mo/ visitors to ,texas' mo/ colorful canyon are n attract$ by its int]e/+ hi/ory4 ,!y come in/ead to enjoy ! sc5]y & recreational opportunities t are pres5t4 ,^! are readily accessible1 = a c>efully eng9e]$1 h>d-surface road leads f ! rim ( ! canyon to ! canyon floor4 ,!re are campgr\nds1 picnic areas1 concessions1 & ev5 an outdoor !atre 7fig4 #bc74 ,! location ( ^! facilities & "s ( ! canyon's m int]e/+ geologic features are %[n on ! g5]aliz$ place map ( ! canyon 7fig4 #b74 ,?is publication does n attempt to describe ! sc5ic beauty ( ,palo ,duro ,canyon1 = ?is mu/ be se5 to be appreciat$4 ,r1 x discusses ! geologic sett+ & orig9 ( ! canyon1 ! me?ods by :i* "s ( ! m int]e/+ geologic features 7 =m$1 & briefly reviews ! hi/ory ( ! area4 ,hopefully1 x w enable ! visitor to und]/& bett] ! mean+ beh9d ! canyon sc5]y1 !reby enhanc+ 8 visit4 ,,ackn[l$gm5ts ,_m p h assi/$ 9 ! prep>ation ( ,! ,geologic ,/ory ( ,palo ,duro ,canyon1 & _! help is gratefully ackn[l$g$3 ,pr(essor ,jack ,t4 ,hughes1 ,dr4 ,frank ,w4 ,daugh]ty1 ,dr4 ,rob]t ,c4 ,burton1 ,meade ,humphries1 & ,jim ,hughes ( ! ,we/ ,texas ,/ate ,univ]sity ,geology ,dep>tm5t provid$ mu* in=mation ab\t ! area & assi/$ 9 ! field2 help 0 also provid$ by ,mr4 ,pete ,c[>t1 ,mr4 ,e>l ,burtz1 ,mr4 ,j]ry ,ts*aun]1 ,mr4 ,bob ,watson1 ,mr4 ,k+1 & o!r p>k p]sonnel2 ,mr4 ,c4 ,boone ,mc,clure1 ( ! ,panh&le-,pla9s ,hi/orical ,museum1 furni%$ "s ( ! photographs2 ,mr4 ,j4 ,dan ,scurlock1 ,mr4 ,bill ,coll9s1 & ,mr4 ,h>old ,allums1 ( ! ,texas ,p>ks & ,wildlife ,dep>tm5t1 made available c]ta9 maps & /ati/ical data2 ,mrs4 ,ples ,h>p] ( ,canyon assi/$ 9 assembl+ in=mation & photographs = ! ,pione] ,amphi!atre2 & ! a]ial photograph ( ,palo ,duro ,canyon 0 tak5 by ,mr4 ,w4 ,a4 ,he/] & made available ?r\gh ! c\rtesy ( ,mr4 ,*>les ,a4 ,wolfl9 ( ,am>illo4 ,drs4 ,pet] ,t4 ,flawn1 ,pet] ,u4 ,rodda1 & ,ross ,a4 ,maxwell ( ! ,bureau ( ,economic ,geology read mu* ( ! manuscript & (f]$ _m helpful sugge/ions1 & ,mr4 ,a4 ,ri*>d ,smi? provid$ special in=mation on caves 9 ! ,palo ,duro area4 ,special ?anks are due to ,miss ,joseph9e ,casey :o edit$ ! manuscript & to ,mr4 ,j4 ,w4 ,macon1 c>tograph]1 :o assum$ responsibility = prep>+ ! maps4 ,?anks are due also to my wife1 ,j5nie1 :o critically read ! manuscript & took a numb] ( ! photographs4 ,f9ally1 ,i w\ld l to ?ank ,dr4 ,j4 ,daniel ,p[ell ( ,! ,univ]sity ( ,texas at ,arl+ton = invaluable assi/ance 9 ! field & 8 en?usia/ic co-op]ation ?r\gh\t ! project4 ,,p>k ,,hi/ory ,palo ,duro ,canyon's long & colorful pa/ has creat$ consid]able int]e/ among hi/orians1 ar*eologi/s1 & geologi/s4 ,hi/orians h trac$ ! writt5 hi/ory ( man & 8 effect on ! ,palo ,duro area1 b ar*eologi/s h delv$ mu* fur!r into ! pa/4 ,!y h s\ght out & /udi$ ! m endur+ records ( ! canyon's e>ly inhabitants--_! tools1 ut5sils1 & weapons4 ,! geologi/1 h[ev]1 is int]e/$ 9 hi/ory t f> ant$ates ev5 ! mo/ primitive human inhabitant ( ! canyon4 ,! e>? sci5ti/ has prob$ ! geologic record ( ! ,palo ,duro area1 us+ rocks1 m9]als1 & fossils z clues to ! geologic hi/ory & developm5t ( ! canyon4 ,palo ,duro ,canyon is unique among ,texas' ,/ate p>ks because ( its _m contributions to hi/ory1 ar*eology1 & geology4 ,"h ! writt5 record1 ! artifacts ( prehi/oric man1 & ! geologic =mations ov]lap & complem5t ea* o!r 9 _m respects4 ,al?\gh ?is guidebook is prim>ily conc]n$ ) ! geologic hi/ory ( ! canyon1 a brief review ( its human hi/ory is also includ$4 ,,anci5t ,,man ,,9 ,,palo ,,duro ,,canyon ,ar*eological /udies indicate t ! e>lie/ kn[n inhabitants ( ,palo ,duro ,canyon liv$ 9 ! canyon f ab\t #aj1jjj to #e1jjj ,b4,c4 ,^! e>ly m5 app>5tly hunt$ ! bison & n[-ext9ct elephant-l mammo?s t roam$ ! ,palo ,duro area dur+ ! ,ice ,age ( ,plei/oc5e "t 7see geologic "t scale1 fig4 #f74 ,_! /one weapons & o!r artifacts h be5 f\nd 9 & ar\nd ! canyon4 ,x is assum$ t ^! primitive p--l ^? :o came lat]--7 attract$ by ! /reams & spr+s t are f\nd 9 ! canyon & by game t came !re to fe$4 ,!re is also evid5ce t ! ,indians took advantage ( c]ta9 ( ! canyon's geologic features4 ,!y fa%ion$ tools1 weapons1 & ut5sils f ! rocks expos$ 9 ! canyon & us$ c]ta9 ( ! %all[ caves & rock %elt]s z _! homes4 ,,indians ,,( ,,! ,,pla9s ,v>i\s tribes ( ,pla9s ,indians ( hi/oric times also us$ ,palo ,duro ,canyon z a camp+ gr\nd4 ,! pres5ce ( ^! ,indians is kn[n f _m campsites & burials4 ,9 addition1 fl9t *ips & /one artifacts1 pot%]ds1 ornam5ts ( %ell & bone1 gr9d+ slabs1 /one mort>s 7fig4 #ae71 & a few pictographs 7fig4 #c7 h provid$ consid]able in=mation ab\t ! culture ( ^! p4 ,among ! tribes believ$ to h frequ5t$ ! canyon at v>i\s times are ! ,apa*es1 ,*ey5nes1 ,arapahos1 ,ki[as1 & ,coman*es4 ,h[ev]1 x is ! ,coman*es :o are mo/ closely associat$ ) ! ,palo ,duro area1 = ! canyon is locat$ ne> ! c5t] ( _! la/ homel&4 ,inde$ x 0 "h t ! ,coman*es 7 f9ally defeat$ & driv5 f ?is "p ( ! ,pla9s4 ,! battlefield :]e ,colonel ,ranald ,mack5zie's troops f\ght ! ,coman*es is locat$ ne> ! s\!a/ corn] ( ! p>k 7see fig4 #g74 ,?is skirmi%1 :i* took place 9 #ahgd1 is believ$ to h be5 ! la/ major ,indian battle 9 ,texas4 ,al?\gh mo/ ( ! canyon's ar*eological sites h be5 pick$ ov] & _m ( ! artifacts remov$1 important f9ds are /ill occasionally report$4 ,p>k visitors :o make discov]ies ( ?is type are urg$ to report !m to a p>k rang] 9 ord] t !y might be call$ to ! att5tion ( ! prop] au?orities4 ,,adv5t ,,( ,,! ,,:ite ,,man ,al?\gh ! hi/ory ( ,palo ,duro ,canyon is ri* 9 ,indian lore1 x 0 ! com+ ( ! :ite man t h]ald$ ! developm5t ( ! area4 ,today x is g5]ally believ$ t ,francisco ,vasquez de ,coronado 0 ! fir/ :ite man to view ! canyon4 ,coronado & 8 m5 are ?\ght to h camp$ "h dur+ ! w9t] ( #aeda1 z !y cross$ ! ,high ,pla9s 9 se>* ( ! fabl$ ,sev5 ,cities ( ,cibola4 ,illu/ration3 ,fig4 #b4 ,place map ( ,palo ,duro ,canyon4 ,lat]1 dur+ ! #ag? & #ah? c5turies1 ! canyon 0 a favorite re/+ place ( ! buffalo hunt]s & ,indian trad]s :o frequ5t$ ! ,pla9s4 ,! canyon 0 also popul> dur+ ! fir/ half ( ! #ai? c5tury1 = x 0 !n t x 0 occupi$ by ! ,coman*es & s]v$ z a trade c5t] = ! ,spani>ds & ,indians :o came f ,new ,mexico4 ,^! trad]s1 call$ coman*]os1 b>t]$ = loot tak5 by ! ,coman*es on _! raids ( e>ly settlem5ts & wagon tra9s t pass$ ?r\gh ! ,panh&le-,pla9s region4 ,?is same era m>k$ ! beg9n+ ( ,am]ican int]e/ 9 ! ,palo ,duro c\ntry4 ,dur+ ?is p]iod ! area 0 visit$ by sev]al exp$itions includ+ ^? ( ,long & ,pike & ! ,texas-,santa ,fe ,exp$ition ( #ahda4 ,h[ev]1 ! canyon 0 n fully explor$ or mapp$ until #aheb4 ,?is important survey 0 c>ri$ out by a p>ty :i* 0 "u ! sup]vision ( ,capta9 ,r4 ,b4 ,m>cy4 ,b x 0 n until #ahgf t ! fir/ :ite man e/abli%$ p]man5t resid5ce 9 ,palo ,duro ,canyon4 ,9 #ahgf--;j two ye>s aft] ,mc,kenzie's r\t ( ! ,coman*es--,colonel ,*>les ,goodnight h]d$ m ?an #a1fjj head ( cattle into ! canyon4 ,"h he laid out 8 fir/ p]man5t ran* & liv$ 9 a primitive e>!n dug\t4 ,n only 0 ,goodnight's ,palo ,duro ,ran* ! fir/ 9 ! canyon1 x is also ?\ght to h be5 ! fir/ comm]cial cattle ran* 9 ! ,texas ,panh&le4 ,9 lat] ye>s ,colonel ,goodnight =m$ a p>tn]%ip ) ,john ,adair ( ,irel&1 & toge!r !y develop$ ! fam\s ,,ja ,ran*--a va/ spread ( "s #fjj1jjj acres4 ,today's visitor to ,palo ,duro ,canyon c visit a p>tially re/or$ dug\t simil> to t occupi$ by ! canyon's e>ly settl]s 7fig4 #cj74 ,illu/ration3 ,fig4 #c4 ,! face c>v$ on ?is b\ld] c be se5 along ! track ( ! ,sad ,monkey ,railroad 7p4 #ce74 ,x is believ$ to h be5 c>v$ by ,indians4 ,illu/ration3 ,fig4 #d4 ,! w> bonnet1 w> lance1 & head fea!rs ( ,coman*e ,*ief ,quanah ,p>k] c be se5 at ! ,panh&le-,pla9s ,hi/orical ,museum 9 ,canyon4 7,photograph c\rtesy ,panh&le-,pla9s ,hi/orical ,museum47 ,f ! late #ahjjs until ab\t #aicj1 ! ,palo ,duro c\ntry rema9$ ! doma9 ( ! ,panh&le-,pla9s cattleman4 ,x 01 none!less1 a favorite picnic & camp+ spot ( ! resid5ts ( ne>by t[ns & cities4 ,9 #aicc ! recreational pot5tial ( ! canyon 0 f9ally recogniz$ & l& = ! ,palo ,duro ,canyon ,/ate ,p>k 0 pur*as$ by ! ,/ate ( ,texas ) money obta9$ ?r\gh a public rev5ue bond issue4 ,today1 mo/ ( ! p>k rev5ue receiv$ ?r\gh gate admissions1 concession receipts1 & m9]al leases goes into a fund t pays (f ! rema9+ balance ( ! rev5ue bonds4 ,dur+ ! initial phase ( ! p>k's developm5t1 mo/ ( ! improvem5ts 9 ! area 7 made by memb]s ( ! ,civilian ,cons]vation ,corps :o work$ "u ! sup]vision ( ! ,national ,p>k ,s]vice4 ,curr5tly1 ,palo ,duro ,canyon ,/ate ,p>k is visit$ by approximately #cjj1jjj visitors ea* ye> & is "o ( ! ,/ate's m popul> recreational & sc5ic areas4 ,,regional ,,sett+ ,palo ,duro ,canyon ,/ate ,p>k is locat$ 9 ! ,panh&le ( ,texas 7fig4 #e7 approximately #ac miles ea/ ( ,canyon on ,/ate ,highway #bag 7see fig4 #g74 ,x is ab\t #ab miles s\? & #h miles ea/ ( ,am>illo via ,ran* ,road #aeda :i* int]sects ,/ate ,highway #bag4 ,! p>k includes m ?an #ae1jjj acres ( ,palo ,duro ,canyon1 a complexly dissect$ area :i* spreads into ,r&all1 ,arm/rong1 & ,briscoe c\nties4 ,m specifically1 ! ,palo ,duro area is situat$ on ! ,llano ,e/acado or ,high ,pla9s area :i* comprises approximately #bj1jjj squ>e miles ( ,texas & ,new ,mexico 7see fig4 #e74 ,g5]ally speak+1 ! ,llano ,e/acado is a high isolat$ plateau or broad mesa1 ris+ above ! surr\nd+ roll+ pla9s 9 a ne>ly flat1 isl&-l mass4 ,on ! we/1 s\?we/1 & s\?1 ! ,llano ,e/acado is b\nd$ by ! valley ( ! ,pecos ,riv]1 :ile its ea/]n esc>pm5t is dra9$ by ! headwat]s ( ! ,r$1 ,brazos1 & ,colorado ,riv]s4 ,! rim ( ,palo ,duro ,canyon is =m$ by ! ,ea/]n ,caprock ,esc>pm5t4 ,caprock is ! t]m us$ to describe a massive lay] ( calc>e\s rock :i* supports ! ,high ,pla9s surface 7see p4 #bf74 ,because x is m resi/ant to =ces ( erosion ?an ! s(t]1 und]ly+ m or less horizontal /rata1 ! caprock =ms an abrupt1 precipit\s esc>pm5t at ! edge ( ! ,high ,pla9s4 ,) ! exception ( ! resi/ant caprock1 h[ev]1 ! surficial deposits on ! ,high ,pla9s are = ! mo/ "p unconsolidat$ s$im5ts4 ,! ,llano ,e/acado is ess5tially devoid ( native trees & is *>act]iz$ by a sp>se1 b uni=m1 cov]+ ( grasses4 ,! surface rocks are ( ,t]ti>y & ,quat]n>y age 7see geologic "t scale1 fig4 #f7 & h a g5]al ea/]ly to s\!a/]ly slope ( ab\t #i feet p] mile4 ,9 ! vic9ity ( ,palo ,duro ,canyon1 rocks ( ,late ,c5ozoic age are directly und]la9 by ,p]mian & ,triassic =mations4 ,^! ,p]mian & ,triassic rocks1 :i* are discuss$ else:]e 9 ?is publication1 are n normally expos$ except 9 deeply erod$ areas su* z ! canyon4 ,illu/ration3 ,fig4 #e4 ,g5]aliz$ geologic map ( ! ,texas ,panh&le %[+ location ( ,palo ,duro ,canyon4 ,%[+3 ,q ,t ,plei/oc5e & ,plioc5e undiff]5tiat$ ,trdo ,dockum ,gr\p 7,triassic7 ,p ,p]mian undiff]5tiat$ ,,! ,,geologic ,,/ory ,,! ,,canyon',s ,,rocks ,,& ,,m9]als ,palo ,duro visitors--reg>dless ( age--seem to h an innate curiosity ab\t ! canyon's rocks4 ,?is is n surpris+1 = mo/ ( ! features ( ! p>k l&scape are compos$ ( or h be5 sculptur$ f solid rock4 ,9 %ort1 mu* ( ! natural beauty ( ,palo ,duro ,canyon has be5 d]iv$ f ! "* ( its expos$ rock =mations & ! effect ( geologic ag5ts ^u !m4 ,because rocks are ! raw mat]ials ( geology & ! /uff f :i* l&scapes are =m$1 x w be helpful = ! visitor to "k some?+ ab\t ! g5]al *>act]i/ics ( rocks & _! role 9 ! developm5t ( ! l&scape4 ,rock is ev]y:]e ar\nd u & is "o ( ! mo/ common objects 9 ! _w1 yet few p c actually def9e a rock4 ,s1 at ! outset x %\ld be /at$ t a rock is a naturally =m$ aggregate ( m9]als1 & a m9]al is a naturally occurr+ sub/ance :i* has a fairly def9ite *emical composition1 di/9ctive physical prop]ties1 *>act]i/ic int]nal /ructure1 & :i* commonly occurs 9 def9ite %apes call$ cry/als4 ,al?\gh n an exact sci5tific or legal def9ition ( a m9]al1 ! above explanation is satisfactory = ! purposes ( ?is publication4 ,al?\gh mo/ visitors %[ consid]able int]e/ 9 ! canyon's rocks & m9]als1 few ( !m "k ! /ory beh9d ! rocks4 ,!y d n "k h[ ! rocks 7 =m$1 ( :at !y are compos$1 h[ !y *ange1 & h[ !y diff]4 ,m important1 !y fail to realize ! hi/orical significance ( ! rocks & h[ !y c be us$ to int]pret ev5ts t occurr$ 9 ! canyon _m millions ( ye>s ago4 ,?us1 be=e "o /udies ! geologic /ory ( ,palo ,duro ,canyon1 x is helpful to "k some?+ ab\t ! v>i\s k9ds ( rocks4 ,!re are ?ree major classes ( rocks 9 ! e>?'s cru/3 igne\s1 s$im5t>y1 & metamorphic rocks4 ,igne\s rocks solidifi$ f an orig9al molt5 /ate4 ,common examples ( igne\s rocks include granite1 basalt1 & volcanic a%4 ,al?\gh no igne\s rocks are f\nd 9 ,palo ,duro ,canyon1 !y are widely expos$ 9 p>ts ( ,we/ & ,c5tral ,texas4 ,metamorphic rocks 7 orig9ally igne\s or s$im5t>y 9 orig94 ,h[ev]1 ^! rocks h und]gone su* great physical & *emical *ange t !y h be5 trans=m$ into a diff]5t k9d ( rock4 ,?us1 metamorphic *anges alt] lime/one to m>ble or s&/one to qu>tzite4 ,no metamorphic rocks crop out 9 ! canyon1 b1 l ! igne\s rocks1 !y are common 9 "s p>ts ( ! ,/ate4 ,all ( ! geologic =mations expos$ 9 ,palo ,duro ,canyon are compos$ ( s$im5t>y rocks4 ,^! are rocks t h be5 =m$ by ! compaction & cem5tation ( rock & m9]al fragm5ts call$ s$im5ts1 or by ! precipitation ( mat]ial f solution4 ,s&/one1 conglom]ate1 %ale1 & cali*e 7see p4 #bf7 are examples ( s$im5t>y rocks t are expos$ 9 ! canyon4 ,s$im5t>y rocks are typically /ratifi$1 t is1 !y occur 9 lay]s or b$s call$ /rata4 ,9 addition1 s$im5t>y rocks--especially ^? ( m>9e orig9--commonly conta9 fossils4 ,^! fossils are traces or evid5ce ( prehi/oric plants & animals t h be5 pres]v$ 9 ! rocks1 & !y may provide clues z to ! age ( rocks & ! mann] 9 :i* !y 7 =m$4 ,fossil rema9s h be5 f\nd at a numb] ( places 9 ! p>k & ^! are discuss$ lat]4 ,,unravel+ ,,e>? ,,hi/ory ,9 ord] to und]/& bett] ! geologic hi/ory & developm5t ( ! canyon1 "o %\ld also h "s k ( ! basic pr9ciples ( e>? hi/ory & %\ld be famili> ) ! geologic "t scale 7fig4 #f74 ,illu/ration3 ,fig4 #f4 ,geologic "t scale4 ,reproduc$ f ,,fossils3 ,an ,introduction to ,prehi/oric ,life1 ,william ,h4 ,mat!ws ,,iii1 ,b>nes & ,noble1 ,inc41 #aifb4 ,,geologic ,,"t ,,scale ,,era ,,p]iod ,,epo* ,,succession ,,( ,,life ,,c5ozoic 8,,rec5t ,,life0 ,,quat]n>y #j-a ,,million ,,ye>s ,rec5t ,plei/oc5e ,,t]ti>y #fb ,,million ,,ye>s ,plioc5e ,mioc5e ,oligoc5e ,eoc5e ,paleoc5e ,,mesozoic 8,,middle ,,life0 ,,cretace\s #gb ,,million ,,ye>s ,,jurassic #df ,,million ,,ye>s ,,triassic #di ,,million ,,ye>s ,,paleozoic 8,,anci5t ,,life0 ,,p]mian #ej ,,million ,,ye>s ,,c>bonif]\s ,,p5nsylvanian #cj ,,million ,,ye>s ,,mississippian #ce ,,million ,,ye>s ,,devonian #fj ,,million ,,ye>s ,,silurian #bj ,,million ,,ye>s ,,ordovician #ge ,,million ,,ye>s ,,cambrian #ajj ,,million ,,ye>s ,,precambrian ,,eras ,,prot]ozoic ,,era ,,ar*eozoic ,,era ,,approximate ,,age ,,( ,,! ,,e>? ,,m ,,?an #d ,,billion #eej ,,million ,,ye>s ,! geologi/ has le>n$ t ! e>?'s physical features h n always be5 z !y are today4 ,x is kn[n1 = example1 t m\nta9s n[ occupy ! sites ( anci5t seas4 ,coal is n[ be+ m9$ :]e swamps exi/$ _m millions ( ye>s ago4 ,fur!rmore1 ! e>?'s plants & animals h also be5 subject to great *ange4 ,! tr5d ( ?is organic *ange is1 9 g5]al1 t[>d m complex & advanc$ =ms ( life4 ,h[ev]1 "s =ms h rema9$ virtually unalt]$ :ile o!rs h become ext9ct at diff]5t po9ts 9 geologic "t4 ,9 ord] to int]pret e>? hi/ory1 ! e>? sci5ti/ ga!rs evid5ce ( ! great *anges 9 climate1 geography1 & life t took place 9 ! geologic pa/4 ,he does ?is by /udy+ ! rock =mations1 ! /ructural relation%ips ( ^! =mations1 & ! l&=ms ( ! area4 ,! record ( anci5t ev5ts is piec$ toge!r by /udy+ ! /ony lay]s ( ! e>? z "o might /udy a giant hi/ory book4 ,inde$1 ! s$im5t>y rocks are ! rocky 8pages0 ( e>? hi/ory1 = 9 !m we f9d ! tracks & trails1 & bones & /ones1 :i* reveal ! intrigu+ /ory ( life long ago4 ,mu* ( ! basic in=mation :i* ! geologi/ uses to recon/ruct ! geologic hi/ory ( a region comes f 8 exam9ation & int]pretation ( b$rock outcrops4 ,b$rock is ! solid unwea!r$ rock :i* und]lies loose e>? mat]ial su* z soil1 s&1 & gravel4 ,an outcrop1 or exposure1 is a place :]e b$rock is expos$ at ! surface4 ,! fir/ *apt] ( e>? hi/ory beg9s ) ! mo/ anci5t rocks kn[n4 ,because !y 7 =m$ e>ly 9 geologic "t1 ^! rocks are normally f\nd deeply buri$ b5ea? y\ng] rocks :i* h be5 deposit$ on top ( !m4 ,x is = ?is reason t e>? hi/ory is read f ! bottom up1 = ! e>lie/ =m$ rock lay]s correspond to ! op5+ *apt] 9 our e>!n hi/ory book4 ,! lat] *apt]s are f\nd 9 ! upp] y\ng] rocks :i* are locat$ ne>] ! surface4 ,?us1 9 8read+0 ! geologic hi/ory ( ,palo ,duro ,canyon we />t ) ! olde/ 8*apt]0 :i* is record$ 9 ! ,qu>t]ma/] ,=mation 7p4 #ag7 ( ,p]mian age1 = ^! are ! olde/ rocks expos$ 9 ! canyon4 ,b deciph]+ e>? hi/ory is n z simple z x might appe>4 ,9 _m areas ! rock lay]s are n always f\nd 9 ! sequ5ce 9 :i* !y 7 orig9ally deposit$4 ,9 places1 great /ructural di/urbances h caus$ "s ( ! rocky 8pages0 to become %uffl$ & out ( place2 o!rs may be miss+ completely4 ,_m rocks h be5 de/roy$ by wea!r+ & erosion or greatly alt]$ by metamorphism4 ,z a result1 ! /ory record$ 9 ^! p>ticul> rocks is lo/ =ev]4 ,^! miss+ 8pages0 make ! anci5t /ory ev5 m difficult to int]pret s ! geologi/ mu/ !n dep5d on o!r evid5ce t w p]mit him to 8fill 9 ! blanks40 ,! record reveal$ 9 ! rocks indicates t our planet is at lea/ #d billion ye>s old & t life has be5 pres5t = m ?an #c billion ye>s4 ,dur+ ?is va/ span ( "t ! e>? & its inhabitants h und]gone _m *anges4 ,,! ,,geologic ,,column ,,& ,,geologic ,,"t ,,scale ,! geologic column ref]s to ! total succession ( rocks1 f ! olde/ to ! mo/ rec5t1 t are f\nd 9 ! entire e>? or 9 a giv5 area4 ,= example1 ! geologic column ( ,texas includes all rock divisions kn[n to be pres5t 9 ! ,/ate4 ,by ! same tok51 ! geologic column ( ,palo ,duro ,canyon consi/s ( ! geologic =mations expos$ !re4 ,?us1 by ref]r+ to ! geologic column previ\sly det]m9$ = a specific area1 ! geologi/ c det]m9e :at type ( rock he might expect to f9d 9 t p>ticul> region4 ,! geologic "t scale 7fig4 #f7 is compos$ ( nam$ int]vals ( geologic "t dur+ :i* 7 deposit$ ! rocks ( ! geologic column4 ,^! "t int]vals be> ! same names t are us$ to di/+ui% ! v>i\s units ( ! geologic column4 ,= example1 "o c speak ( ,p]mian "t 7ref]r+ to ! geologic "t scale7 or ( ,p]mian rocks 7ref]r+ to rock units ( ,p]mian age 9 ! geologic column74 ,bo? ! geologic column & ! geologic "t scale are bas$ ^u ! pr9ciple ( sup]position4 ,?is basic geologic concept /ates t unless a s]ies ( s$im5t>y rock has be5 ov]turn$1 a giv5 rock lay] is old] ?an ! /rata above x1 & y\ng] ?an all ( ! lay]s bel[ x4 ,?us1 ! field relation%ip ( ! rocks plus ! type ( fossils 7if pres5t7 give ! geologi/ "s indication ( ! relative age ( ! rocks4 ,relative age does n imply age 9 ye>s2 r1 x fixes age 9 relation to o!r ev5ts t are record$ 9 ! rocks4 ,)9 rec5t ye>s1 h[ev]1 x has become possible to assign ages 9 ye>s to c]ta9 rock units4 ,?is is accompli%$ by a sy/em ( rock dat+ bas$ on v precise measurem5ts ( am\nts ( radioactive elem5ts 7su* z uranium74 ,:5 pres5t 9 ! rocks1 radioactive m9]als *ange or decay at a kn[n rate s t !y are natural 8clocks40 ,?is me?od ( dat+ has made x possible to devise a "t scale 9 ye>s :i* gives "s idea ( ! trem5d\s am\nt ( "t t has pass$ s9ce ! olde/ kn[n rocks 7 =m$4 ,x has also be5 us$ to v]ify ! previ\sly det]m9$ relative ages ( ! v>i\s rock units4 ,! l>ge/ unit ( geologic "t is an era1 & ea* era is divid$ into small] "t units call$ p]iods4 ,a p]iod ( geologic "t is divid$ into epo*s1 :i*1 9 turn1 may be subdivid$ into /ill small] units4 ,! geologic "t scale might be r\ghly comp>$ to ! cal5d> 9 :i* ! ye> is divid$ into mon?s1 mon?s into weeks1 & weeks into days4 ,unlike ye>s1 h[ev]1 geologic "t units are arbitr>y & ( unequal duration1 & ! geologi/ _c be positive ab\t ! exact l5g? ( "t involv$ 9 ea* unit4 ,! "t scale does1 h[ev]1 provide a /&>d by :i* he c discuss ! age ( fossils & _! surr\nd+ rocks4 ,by ref]r+ to ! "t scale x may be possible1 = in/ance1 to /ate t a c]ta9 ev5t occurr$ dur+ ! ,paleozoic ,era 9 ! same s5se t "o might say t some?+ happ5$ dur+ ! ,am]ican ,revolution4 ,!re are five eras ( geologic "t1 & ea* has be5 giv5 a "n t is descriptive ( ! degree ( life developm5t t *>act]izes t era4 ,h5ce1 ,paleozoic means 8anci5t-life0 & ! era 0 s nam$ because ( ! relatively simple & anci5t /age ( life developm5t4 ,! eras1 a guide to _! pronunciation1 & ! lit]al translation ( ea* "n is %[n bel[4 ,c5ozoic 7,,see-no-zo-ic7--8rec5t-life0 ,mesozoic 7,,mes-o-zo-ic7--8middle-life0 ,paleozoic 7,,pay-lee-o-zo-ic7--8anci5t-life0 ,prot]ozoic 7,,pro-t]-o-zo-ic7--8e>li]-life0 ,ar*eozoic 7,,ar-kee-o-zo-ic7--8beg9n+-life0 ,ar*eozoic & ,prot]ozoic rocks are commonly gr\p$ toge!r & ref]r$ to z ,precambrian 9 age4 ,9 mo/ places ,precambrian rocks h be5 greatly contort$ & metamorphos$1 & ! record ( ?is portion ( e>? hi/ory is mo/ difficult to int]pret4 ,precambrian "t repres5ts t portion ( geologic "t f ! beg9n+ ( e>? hi/ory until ! deposition ( ! e>lie/ fossilif]\s ,cambrian /rata4 ,precambrian "t probably repres5ts z mu* z #he p]c5t ( all geologic "t4 ,! olde/ era is at ! bottom ( ! "t scale because ?is "p ( geologic "t transpir$ fir/ & 0 !n foll[$ by ! successively y\ng] eras :i* are plac$ above x4 ,?is is1 ( c\rse1 ! ord] 9 :i* ! v>i\s portions ( geologic "t occurr$ & dur+ :i* ! correspond+ rocks 7 =m$4 ,z m5tion$ above1 ea* ( ! eras has be5 divid$ into p]iods1 & mo/ ( ^! p]iods d]ive _! names f ! regions 9 :i* ! rocks ( ea* 7 fir/ /udi$4 ,= example1 ! ,p5nsylvanian rocks ( ,nor? ,am]ica 7 fir/ /udi$ 9 ! ,/ate ( ,p5nsylvania4 ,illu/ration3 ,fig4 #g4 ,g5]aliz$ geologic map ( ,palo ,duro ,canyon ,/ate ,p>k4 ,,explanation ,q ,t ,plei/oc5e & ,plioc5e undiff]5tiat$ ,rdo ,dockum ,gr\p ,p ,p]mian undiff]5tiat$ ,! ,paleozoic ,era has be5 divid$ into sev5 p]iods ( geologic "t4 ,) ! olde/ at ! bottom ( ! li/1 ^! p]iods & ! s\rce ( _! names are3 ,p]mian 7,,pur-me-un7--f ! ,prov9ce ( ,p]m 9 ,russia ,p5nsylvanian 7p5-sil-,,va9-yun7--f ! ,/ate ( ,p5nsylvania ,mississippian 7miss-i-,,sip-i-un7--f ! ,upp] ,mississippi ,valley ,devonian 7de-,,vo-ni-un7--f ,devon%ire1 ,engl& ,silurian 7si-,,loo-ri-un7--= ! ,silures1 an anci5t tribe ( ,brita9 ,ordovician 7or-doe-,,vi%-un7--= ! ,ordovices1 an anci5t tribe ( ,brita9 ,cambrian 7,,kam-bri-un7--f ! ,lat9 ^w ,cambria1 mean+ ,wales ,! ,c>bonif]\s ,p]iod 9 ,europe includes ! ,mississippian & ,p5nsylvanian ,p]iods ( ,nor? ,am]ica4 ,al?\gh ?is classification is no long] us$ 9 ! ,unit$ ,/ates1 ! t]m ,c>bonif]\s is f\nd 9 _m ( ! e>li] geological publications & on _m ( ! e>li] geologic maps4 ,! p]iods ( ! ,mesozoic ,era & ! s\rce ( _! names are3 ,cretace\s 7cre-,,tay-%us7--f ! ,lat9 ^w creta1 mean+ *alky ,jurassic 7joo-,,ras-ik7--f ! ,jura ,m\nta9s ( ,europe ,triassic 7try-,,ass-ik7--f ! ,lat9 ^w triad1 mean+ ?ree ,! ,c5ozoic p]iods d]iv$ _! names f an old outdat$ sy/em ( classification :i* divid$ all ( ! e>?'s rocks into f\r gr\ps4 ,! two divisions li/$ bel[ are ! only names ( ?is sy/em :i* are /ill 9 use3 ,quat]n>y 7kwah-,,tur-nuh-ri7 ,t]ti>y 7,,tur-%i-ri7 ,al?\gh ! units nam$ above are ! major divisions ( geologic "t & ( ! geologic column1 ! geologi/ g5]ally works ) small] units ( ! column call$ geologic =mations4 ,a geologic =mation is a unit ( rock t is recogniz$ by c]ta9 physical & *emical *>act]i/ics4 ,a =mation is g5]ally giv5 a d\ble "n :i* indicates bo? :]e x is expos$ & ! type ( rock t makes up ! bulk ( ! =mation4 ,= example1 ! ,beaumont ,clay is a =mation consi/+ ( clay deposits t are f\nd 9 & ar\nd ,beaumont1 ,texas4 ,= conv5i5ce 9 /udy1 two or m successive & adjo9+ =mations may be plac$ toge!r 9 a gr\p4 ,?us1 ! ,tecovas & ,trujillo ,=mations h be5 plac$ 9 ! ,dockum ,gr\p4 ,likewise1 a =mation may be subdivid$ into small] units su* z memb]s1 :i* may also be giv5 geographic or li?ologic 7rock type7 names4 ,,geologic ,,=mations ,,expos$ ,,9 ,,palo ,,duro ,,canyon ,z not$ above1 all ( ! rocks :i* crop out 9 ,palo ,duro ,canyon are s$im5t>y 9 orig94 ,!y repres5t f\r diff]5t geological p]iods3 ! ,p]mian1 ,triassic1 ,t]ti>y1 & ,quat]n>y 7fig4 #ab74 ,al?\gh ^! rock =mations diff] consid]ably 9 composition & age1 !y d n tell ! :ole geologic /ory ( ! area4 ,long spans ( geologic "t are n repres5t$ by rock units because ! region 0 und]go+ erosion or no s$im5ts 7 be+ deposit$ dur+ c]ta9 portions ( geologic "t4 ,rocks t _h =m$ dur+ "o geologic p]iod 7 remov$ by erosion dur+ a lat] p]iod4 ,?us1 segm5ts ( ! geologic record 7 de/roy$ or nev] record$4 ,= ?is reason1 mu* ( ! geologic hi/ory ( ! ,palo ,duro area is unrecord$ & mu/ be inf]r$ f fragm5t>y evid5ce borr[$ & piec$ toge!r f adjac5t areas4 ,ev5 s1 an int]e/+ /ory c be assembl$ f ! rocks t rema9 9 ! canyon today4 ,9 g5]al1 ! foll[+ descriptions ( ! =mations expos$ 9 ,palo ,duro ,canyon ,/ate ,p>k foll[ ! proc$ure t mo/ geologi/s use 9 pres5t+ ! results ( _! geologic inve/igations4 ,! m di/9ctive *>act]i/ics ( ! rock units are describ$ 9 ord] t !y may be m easily recogniz$1 & ! ways 9 :i* ! rocks 7 =m$ are also consid]$4 ,) ?is backgr\nd x is !n possible to review ! geologic hi/ory record$ 9 ! b$rock ( ! canyon4 ,a simplifi$ geologic map is pres5t$ 9 figure #g2 ?is %[s ! di/ribution ( ! major rock types 9 ! canyon4 ,! read] w f9d x helpful to ref] to ?is map :5 read+ ! descriptions ( ! v>i\s =mations4 ,qu>t]ma/] ,=mation4-- ,! olde/ =mation expos$ 9 ! canyon is ! ,qu>t]ma/] ,=mation ( ,p]mian age 7see fig4 #f7 :i* is nam$ f exposures along ! banks ( ,qu>t]ma/] ,creek 9 ,rog] ,mills ,c\nty1 ,oklahoma4 ,"o ( ! m colorful =mations 9 ! p>k1 ! ,qu>t]ma/] is compos$ prim>ily ( brick-r$ to v]milion %ales :i* are int]b$d$ ) l5ses ( gray %ales1 clays1 mud/ones1 & s&/ones4 ,av]ag+ ab\t #fj feet ?ick :]e expos$ 9 ! p>k1 ! ,qu>t]ma/] =ms ! floor & l[] walls ( ! canyon4 ,! rocks ( ?is =mation are easily exam9$ at _m places ?r\gh\t ! canyon & 9 !m c be se5 a numb] ( int]e/+ geologic ph5om5a4 ,probably ! mo/ noticeable ( ^! features are ! %9+ :ite ve9s ( gypsum t lace ! face ( ! r$ %ale outcrops 7fig4 #h74 ,a s(t1 transp>5t to transluc5t m9]al t c be scrat*$ by a f+]nail1 gypsum is hydr\s calcium sulfate 7,ca,s,o#b;,h,o74 ,?ree v>ieties ( gypsum are f\nd 9 ! canyon3 7#a7 sat9 sp>1 a fibr\s v>iety ) a silky %e52 7#b7 sel5ite1 a colorless1 transp>5t v>iety :i* commonly occurs 9 %eet-l masses2 & 7#c7 a f9e-gra9$ massive v>iety call$ alaba/]4 ,sat9 sp> is ! mo/ common v>iety ( gypsum pres5t & x commonly occurs 9 ?9 b&s int]b$d$ ) ! mud/ones & s&/ones4 ,x is mu* m noticeable 9 ! %ales1 h[ev]1 = x is typically se5 9 n>r[ ve9s :i* criss-cross ! surface ( ! outcrop & int]sect ! b$d+ planes at v>i\s angles4 ,al?\gh normally :ite1 "s ( ! sat9 sp> has a s(t p9k or blui% hue due to ! pres5ce ( impurities 9 ! m9]al4 ,illu/ration3 ,fig4 #h4 ,ve9s ( sel5ite gypsum 7top arr[7 9 ,qu>t]ma/] ,=mation4 ,notice diagonal jo9t to left ( geologi/'s h& 7l[] arr[74 ,! pres5ce ( gypsum 9 ! ,qu>t]ma/] r$ b$s is ( special significance to ! geologi/1 = x provides valuable in=mation ab\t ! geologic hi/ory ( ! ,palo ,duro area4 ,x is kn[n1 = example1 t :5 a l&lock$ body ( sea wat] 9 an arid climate becomes sep>at$ f ! ocean1 "o ( ! mo/ common salts to precipitate is hydr\s calcium sulfate1 or gypsum4 ,gypsum may also be precipitat$ :5 a lake )\t an outlet evaporates 9 an arid climate4 ,geologic evid5ce sugge/s t ! s$im5ts :i* gave rise to ! rocks ( ! ,qu>t]ma/] ,=mation 7 deposit$ 9 a l&lock$ arm ( ! sea dur+ ! latt] "p ( ! ,p]mian ,p]iod4 ,z evaporation cont9u$ & ! sea wat] 0 r$uc$ to approximately "o-?ird ( its orig9al volume1 gypsum 0 precipitat$4 ,!re mu/ h be5 p]iodic influxes ( silt- & mud-be>+ wat]s ent]+ ! anci5t ,p]mian sea1 = lay]s ( %ale & mud/one are int]b$d$ ) ! gypsum4 ,x is believ$ t mu* ( ! sat9 sp> & sel5ite gypsum 0 orig9ally anhydrite 7,ca,s,o74 ,unlike gypsum1 anhydrite does n conta9 wat]1 b x c be *ang$ to gypsum 9 ! pres5ce ( moi/ure4 ,!re are two l9es ( evid5ce t indicate an anhydrite orig9 = ! ,qu>t]ma/] gypsum4 ,fir/1 microscopic exam9ation ( gypsum samples reveals ! pres5ce ( residual anhydrite cry/als emb$d$ 9 ! gypsum4 ,second1 _m ( ! gypsum b$s h be5 squeez$ into r g5tle folds4 ,^! consi/ ( small anticl9es1 upfolds or ar*es1 & syncl9es1 d[nfolds or tr\ghs 7fig4 #i74 ,x has be5 sugge/$ t ?is fold+ took place z ! anhydrite und]w5t hydration1 or took on wat]4 ,z hydration occurr$ & ! anhydrite 0 conv]t$ to gypsum1 ! gypsum exp&$1 !reby ex]t+ bo? lat]al & v]tical pressure on ! b$s ar\nd x4 ,?is produc$ ! crumpl$1 wave-l fold+ s *>act]i/ic ( c]ta9 ( ! gypsum b$s4 ,h[ev]1 !re is n complete agreem5t t ! fold+ 9 ! gypsum is due to ! hydration ( anhydrite4 ,c]ta9 geologi/s attribute ?is de=mation to slump+ caus$ by solution cavities1 = gypsum is relatively easily dissolv$ 9 wat]4 ,z ! gypsum 0 dissolv$ & c>ri$ away 9 solution1 ! removal ( ! support+ lay]s ( gypsum p]mitt$ slump+ & consequ5t de=mation 9 ! ov]ly+ %ales & mud/ones4 ,al?\gh "s geologi/s believe t ! folds 7 caus$ by expansion due to ! hydration ( anhydrite & o!rs support de=mation relat$ to ! removal ( soluble gypsum1 !re is g5]al agreem5t t ! fold+ is local & n relat$ to regional or widespread de=mation4 ,illu/ration3 ,fig4 #i4 ,sagg+ b$s ( ,qu>t]ma/] ,=mation h produc$ ?is g5tle syncl9e1 or d[nfold+1 9 ! rocks4 ,! 8dome0 on ,capitol ,peak c be se5 9 ! backgr\nd4 ,n all ( ! r$ ,qu>t]ma/] %ales are uni=mly color$4 ,"s ( !m conta9 gray-gre51 circul> spots call$ r$uction halos 7fig4 #aj74 ,^! spots1 :i* 9 places give ! r$ %ales a di/9ctive polka-dot appe>ance1 h be5 produc$ z ! result ( *emical *ange ( c]ta9 m9]als )9 ! %ale4 ,z not$ e>li]1 s$im5ts are usually laid d[n 9 horizontal lay]s4 ,h[ev]1 9 c]ta9 environm5ts1 s$im5ts may be deposit$ 9 su* a way t ! lay]s are incl9$ at angle to horizontal 7fig4 #aa74 ,?is /ructure1 call$ cross-b$d+ or cross-/ratification1 is f\nd 9 c]ta9 s&/ones & o!r co>se-gra9$ or fragm5tal s$im5t>y rocks4 ,cross-b$d+ typically consi/s ( r di/9ct incl9$ lay]s sep>at$ by b$d+ planes 7! surface ( dem>cation betwe5 two individual rock lay]s74 ,b$d+ ( ?is type commonly occurs 9 s$im5t>y rocks =m$ 9 riv]s1 deltas1 & along ! m>g9s ( lakes or oceans4 ,! cross-b$d+ 9 ! ,qu>t]ma/] & c]ta9 ( ! ,triassic =mations is believ$ to h be5 develop$ "u simil> conditions4 ,al?\gh cross-b$d+ is also common 9 c]ta9 rocks ( eolian orig9 7deposit$ by w9d7 none ( ! cross-b$d+ 9 ! canyon's rocks is due to ! action ( w9d4 ,9 addition1 "s ( ! ,qu>t]ma/] /rata h ripple m>ks on _! surfaces4 ,^! features are common 9 c]ta9 s$im5t>y rocks & 7 =m$ :5 ! surface ( a b$ ( s$im5t 0 agitat$ by waves or curr5ts4 ,! size1 %ape1 & cross section ( ! ripple m>ks c be us$ to tell :e!r ! m>ks 7 produc$ by waves or curr5ts4 ,! ripple m>ks 9 ! ,qu>t]ma/] appe> to h be5 =m$ by ! action ( waves on a %all[ sea floor4 ,a numb] ( int]e/+ geologic features 9 ! canyon h be5 =m$ 9 "p 9 ! ,qu>t]ma/] ,=mation4 ,^! include ! multi-hu$ ,spani% ,skirts 7fig4 #bf71 ! ,devil's ,slide 7fig4 #ce71 ,capitol ,peak 7fig4 #cb71 & ,cat>9a ,cave 7fig4 #bg74 ,! latt] is a r unusual cave 9 t x has develop$ 9 a l>ge mass ( l&slide debris divid$ by project+ b$rock ( ! ,spani% ,skirts4 ,! cave has be5 =m$ by suffosian1 a process :]eby wat] ent]s ! l&slide debris on ! upp] slopes & foll[s buri$ *annels 9 ! l&slide remov+ rock debris z x passes ?r\gh4 ,! flood wat] exits at ! base ( ! l&slide by means ( ,cat>9a ,cave4 ,! plan ( ! cave closely resembles ! dra9age patt]ns ( surface gullies4 ,tecovas ,=mation4-- ,rocks ( ! ,triassic ,sy/em 7fig4 #f7 are well repres5t$ 9 ,palo ,duro ,canyon & consi/ ( ! ,tecovas & ,trujillo ,=mations4 ,^! =mations are "p ( ! ,dockum ,gr\p ( ,late ,triassic age4 ,hav+ a total ?ickness ( ab\t #bjj feet1 ! ,tecovas 7:i* is nam$ f exposures f\nd on ,tecovas ,creek 9 ,pott] ,c\nty1 ,texas7 consi/s l>gely ( multicolor$ %ales4 ,also pres5t are ?9 lay]s ( s(t s&/one1 :i* are dissem9at$ ?r\gh\t ! %ales1 & a m prom95t b$ ( :ite s&/one1 :i* m>ks ! middle ( ! =mation4 ,! ,tecovas %ales ov]lie ! ,qu>t]ma/] ,=mation1 & ! l[] zone ( lav5d]1 gray1 & :ite %ales =ms a relatively smoo? slope t is easily di/+ui%$ f ! /eep] slopes ( gulli$ r$-&-:ite-b&$ %ales b5ea? !m 7fig4 #ab74 ,illu/ration3 ,fig4 #aj4 ,*emical reactions 9 c]ta9 ( ! r$ ,qu>t]ma/] %ales h produc$ r$uction halos 7p4 #ai7 :i* give ! rocks a polka-dot appe>ance4 ,illu/ration3 ,fig4 #aa4 ,?is b\ld]1 locat$ ne> ! foot ( ,triassic ,peak along ! ,sad ,monkey ,railroad track1 exhibits ! cross-b$d+ typical ( ! ,trujillo s&/ones4 ,b ! contact zone betwe5 ! ,tecovas & ,qu>t]ma/] %ales involves m ?an a m]e *ange 9 color4 ,"h is "o ( ! miss+ 8*apt]s0 9 ! geologic hi/ory ( ! canyon1 = "p ( ! ,late ,p]mian record & all ( ! record ( ,e>ly & ,middle ,triassic "t are miss+ f ! geologic column4 ,su* gaps 9 ! column are repres5t$ by uncon=mities 9 ! rocks4 ,"h ! uncon=mity is an anci5t erosional surface betwe5 ! ,tecovas ,=mation ( ,late ,triassic age & ! ,late ,p]mian ,qu>t]ma/] ,=mation1 & !re are _m millions ( ye>s ( e>? hi/ory repres5t$ 9 ?is miss+ 8*apt]0 9 ! geologic /ory ( ,palo ,duro ,canyon4 ,dur+ ?is va/ span ( "t1 ?\s&s ( feet ( s$im5ts 7 probably deposit$1 conv]t$ into rock1 & !n lat] remov$ by erosion4 ,ne> ! middle ( ! ,tecovas ,=mation !re is a b$ ( :ite1 crumbly 7friable7 s&/one4 ,av]ag+ ab\t #ae feet 9 ?ickness1 ?is s&/one conta9s _m jo9ts 7small crack-l fractures7 along :i* no appreciable movem5t has tak5 place 7fig4 #h74 ,!re are two di/9ct sets ( ^! jo9ts :i* int]sect ea* o!r at "r angles4 ,! di/9ctive jo9t patt]ns1 ! color1 & ! friability ( ?is s&/one cle>ly diff]5tiate x f ! h>d]1 d>k]1 & m co>se-gra9$ s&/ones ( ! ov]ly+ ,trujillo ,=mation 7p4 #bb74 ,! upp] "p ( ! ,tecovas consi/s ( a lay] ( orange %ale :i* ov]lies ! middle s&/one unit & is 9 contact ) ! l[] "p ( ! ,trujillo ,=mation4 ,illu/ration3 ,fig4 #ab4 ,tak5 f ! nor?we/ rim ne> ,coronado ,lodge1 ?is photograph %[s ! f\r major rock units expos$ 9 ! p>k3 7#a7 ,! ,qu>t]ma/] ,=mation :i* =ms ! l[] wall & canyon floor2 7#b7 ,tecovas ,=mation2 7#c7 ,trujillo ,=mation :i* caps ! mesas2 & 7#d7 ,ogallala ,=mation4 ,! fossils :i* h be5 f\nd 9 ! ,tecovas ,=mation sugge/ t ^! rocks 7 d]iv$ f s$im5ts deposit$ 9 swamps & /reams4 ,unlike ! m>9e deposits ( ! ,qu>t]ma/]1 ! rocks ( ! ,tecovas 7 =m$ f cont95tal deposits laid d[n on ! l&4 ,fossils f\nd 9 ! canyon include ! bones & tee? ( ! ext9ct semi-aquatic reptiles kn[n z phytosaurs 7fig4 #ac7 & bone & skull fragm5ts ( a primitive amphibian call$ ,buettn]ia 7fig4 #ad74 ,coprolites 7! fossiliz$ excrem5t ( animals71 pieces ( petrifi$ wood1 & ! tee? & bones ( lungfi% h also be5 report$ f ! ,tecovas4 ,illu/ration3 ,fig4 #ac4 ,! skull ( ?is crocodile-l creature call$ a phytosaur is typical ( ! reptiles t inhabit$ ! ,palo ,duro area dur+ ! ,triassic ,p]iod4 7,photograph c\rtesy ,panh&le-,pla9s ,hi/orical ,museum47 ,a numb] ( m9]als includ+ hematite1 an iron m9]al1 & psilomelane1 a b>ium-magnesium oxide1 occur 9 ! ,tecovas4 ,hematite is an ore ( iron & psilomelane a manganese ore1 ?\gh nei!r ( ^! is pres5t 9 comm]cial quantities 9 ! canyon4 ,! ,tecovas also conta9s a numb] ( concretions :i* range f a fraction ( an in* to z mu* z #f in*es 9 diamet]4 ,^! sph]ical masses are g5]ally h>d] ?an ! f9e-gra9$ %aly s&s 9 :i* !y are f\nd & 7 ?us left beh9d :5 ! surr\nd+ rock 0 erod$ away4 ,"s ( ^! concretions are m>k$ by cracks or ve9s fill$ ) ! m9]al calcite4 ,concretions be>+ ?is type ( /ructure are call$ sept>ia1 or sept>ian concretions4 ,geodes are also f\nd 9 ! ,tecovas ,=mation4 ,^! are r\nd$ concretion>y rocks ) a holl[ int]ior t is frequ5tly l9$ ) m9]al cry/als4 ,well-=m$ cry/als ( cle> calcite h be5 f\nd 9 _m ( ! geodes f ! ,tecovas4 ,among p>k l&m>ks t are *>act]iz$ by ! multi-hu$ ,tecovas /rata are ! middle portion ( ,triassic ,peak 7fig4 #be71 ! upp] "p ( ! ,spani% ,skirts 7fig4 #bf71 ,capitol ,peak 7fig4 #cb71 & ! ,devil's ,slide 7fig4 #ce74 ,trujillo ,=mation4-- ,nam$ f rock exposures on ,trujillo ,creek 9 ,oldham ,c\nty1 ,texas1 ! ,trujillo is easy to di/+ui% f ! und]ly+ ,tecovas ,=mation4 ,! contact is q di/9ct & lies betwe5 ! top ( ! orange ,tecovas %ale & ! base ( ! massive-b$d$1 cliff-=m+ ,trujillo s&/one 7fig4 #be74 ,al?\gh g5]ally f9e gra9$ & ?ickly b$d$1 !re are local conc5trations ( pebble-siz$ rock fragm5ts 9 ! ,trujillo4 ,! wea!r$ surface ( ! l[] s&/one is /a9$ r$ or d>k br[n by iron oxides4 ,h[ev]1 a fre%1 unwea!r$ surface is typically gray or gre5i% gray 9 color1 & c>eful exam9ation ( ! unwea!r$ rock reveals ! pres5ce ( t9y flakes ( mica4 ,! basal ,trujillo s&/one is "o ( ! mo/ conspicu\s rock units 9 ! canyon & =ms _m ( ! prom95t b5*es & mesas s typical ( ! ,palo ,duro l&scape4 ,9 places ! s&/one is cross-b$d$ 7p4 #bj7 & conta9s *annel deposits ( co>se s& :i* sugge/ t ! s$im5ts f :i* x 0 d]iv$ 7 deposit$ 9 anci5t /ream b$s4 ,r$1 m>oon1 & gray %ales ov]lie ! basal s&/one memb] ( ! ,trujillo1 & ^! %ales are ov]la9 by cross-b$d$1 co>se-gra9$ s&/one4 ,ano!r int]val ( v>icolor$ %ales sep>ates ! middle s&/one b$ f ! upp] s&/one memb]4 ,! middle s&/one unit is a conspicu\s l$ge- or cliff-=m+ rock & is m$ium to co>se gra9$ & commonly cross-b$d$4 ,9 mo/ localities1 ! upp] s&/one is ov]la9 by a section ( r$ & gre5 %ales :i* m>k ! upp]mo/ limits ( ! ,trujillo ,=mation4 ,9 places1 h[ev]1 ?is %ale section has be5 remov$ by erosion & rocks ( ,t]ti>y age directly ov]lie ! s&/one4 ,al?\gh fossils are n common1 ! rema9s ( ,buettn]ia 7fig4 #ad71 leaf impr9ts1 pieces ( m9]aliz$ wood1 & ! scatt]$ tee? & bone fragm5ts ( reptiles & amphibians h be5 f\nd4 ,phytosaur rema9s1 especially tee?1 h also be5 collect$ f ! ,trujillo s&/ones4 ,! ,indians :o =m]ly inhabit$ ! ,palo ,duro area 7p4 #c7 put ! rocks ( ! canyon to a numb] ( uses4 ,?is appe>s to be especially true ( ! r co>se-gra9$ ,trujillo s&/ones1 :i* 7 commonly us$ = con/ruct+ primitive rock %elt]s4 ,! abrasive surface ( ! s&/one 0 especially well suit$ = gr9d+ gra91 & mort> holes h be5 f\nd 9 a numb] ( places4 ,"o ( ^! 7fig4 #ae7 c be se5 along ! tracks ( ! ,sad ,monkey ,railroad 7p4 #ce7 ne> ! foot ( ,triassic ,peak4 ,! ,indians also us$ ! clays ( ! ,qu>t]ma/]1 ,tecovas1 & ,trujillo ,=mations to make pott]y1 & iron & copp] m9]als su* z hematite & mala*ite 7 us$ to make r$ & gre5 pigm5ts = decoration & w> pa9t4 ,! ,trujillo %ales & s&/ones c be se5 9 a numb] ( ,palo ,duro's m spectacul> geological oddities4 ,^! erosional remnants are be/ develop$ :]e blocks ( erosion-resi/ant s&/one protect und]ly+ p$e/als ( s(t] %ale 7fig4 #ae74 ,?is type ( diff]5tial wea!r+ 7p4 #ca7 has produc$ a numb] ( int]e/+ & unusually %ap$ p$e/al rocks or 8hoodoos0 7figs4 #af & #bj74 ,! mo/ spectacul> erosional remnant--& "o t has come to be ! 8tradem>k0 ( ,palo ,duro ,canyon--is ! ,ligh?\se 7fig4 #ca74 ,! great jumble ( b\ld]s call$ ! ,rock ,g>d5 7fig4 #cd7 is also compos$ l>gely ( massive blocks ( dislodg$ ,trujillo s&/one4 ,^! b\ld]s accumulat$ on ! canyon floor z a result ( l&slides4 ,9 addition1 ! rock pr(ile kn[n z ,santana's ,face 7fig4 #bh7 is a naturally sculptur$ pr(ile 9 ! ,trujillo s&/one t =ms ! cap ( ,timb] ,mesa4 ,ogallala ,=mation4-- ,! ,ogallala ,=mation is nam$ f exposures ar\nd ,ogallala 9 ,kei? ,c\nty1 ,nebraska4 ,!re is a major uncon=mity betwe5 ! ,trujillo ,=mation ( ! ,triassic & ! ov]ly+ ,ogallala ,=mation ( ,plioc5e 7,late ,t]ti>y7 age4 ,miss+ "h is ! geologic evid5ce = :at may h be5 "s ( ! m excit+ *apt]s 9 ! canyon's hi/ory4 ,!re is no record1 = example1 ( ! ,jurassic & ,cretace\s ,p]iods :i* toge!r encompass almo/ #abj million ye>s ( e>? hi/ory4 ,also miss+ is any evid5ce ( :at transpir$ dur+ m ?an #ij p]c5t ( ! ,t]ti>y ,p]iod1 = no rocks ( ,paleoc5e1 ,eoc5e1 ,oligoc5e1 or ,mioc5e age are expos$ 9 ! canyon4 ,toge!r ^! f\r epo*s comprise approximately #dg million ye>s ( e>? hi/ory4 ,x is impossible1 ( c\rse1 to det]m9e h[ _m geologic =mations may h be5 =m$ & lat] erod$ dur+ ! #afg million ye>s repres5t$ by ?is uncon=mity4 ,h[ev]1 our k ( pres5t-day deposition & erosion sugge/s t ! miss+ geologic record und\bt$ly repres5ts _m ?\s&s ( feet ( rock4 ,illu/ration3 ,fig4 #ad4 ,! skeleton ( ,buettn]ia1 a l>ge amphibian1 f\nd 9 ,upp] ,triassic /rata 9 ! canyon4 7,photograph c\rtesy ,panh&le-,pla9s ,hi/orical ,museum47 ,! l[] portion ( ! ,ogallala ,=mation is compos$ ( a r$di%-br[n1 f9e- to m$ium-gra9$ s&/one t contra/s %>ply ) ! und]ly+ r$ & gre5 %ales t are expos$ 9 ! top ( ! ,trujillo ,=mation4 ,mu* ( ?is s&y rock is *>act]iz$ by pebbles consi/+ ( a v>iety ( igne\s1 s$im5t>y1 & metamorphic rocks4 ,because x consi/s ( rock & m9]al fragm5ts ( v>i$ composition & size1 ?is k9d ( s$im5t>y rock is call$ a conglom]ate4 ,! type ( rock fragm5ts f\nd 9 basal ,ogallala conglom]ates sugge/s t !y 7 transport$ to ! ,panh&le-,pla9s area by /reams fl[+ s\!a/w>d f ! ,rocky ,m\nta9s4 ,z ^! /reams deposit$ _! loads1 !y left beh9d a wide spread blanket ( s&1 gravel1 & mud :i* =m$ an ext5sive alluvial pla9 t ext5d$ f we/]n ,nebraska to nor?we/ ,texas4 ,al?\gh x is less ?an #ajj feet ?ick 9 ,palo ,duro ,canyon1 9 places ?is great mantle ( fluvial 7/ream-deposit$7 s$im5ts is z mu* z #ijj feet ?ick4 ,illu/ration3 ,fig4 #ae4 ,! depression 9 ?is b\ld] is a mort> hole believ$ to h be5 us$ by ! ,indians = gr9d+ corn4 ,illu/ration3 ,fig4 #af4 ,?is p$e/al rock1 locat$ ne> ! ,ligh?\se1 is capp$ by a slab ( wea!r-resi/ant ,trujillo s&/one4 ,mo/ ( ! ,ogallala ,=mation consi/s ( a mixture ( div]se rock types su* z conglom]ate1 s&/one1 silt/one1 clay & m>l4 ,b ! upp] "p ( ! =mation is *>act]iz$ by ?ick cali*e deposits4 ,a dull1 e>?y calcite deposit1 cali*e typically =ms 9 areas ( scant ra9fall4 ,x is believ$ to orig9ate :5 gr\nd moi/ure1 conta9+ dissolv$ calcium bic>bonate1 moves to ! surface :]e ! moi/ure /eadily evaporates leav+ a calcium c>bonate cru/ on or ne> ! surface 7fig4 #ag74 ,cali*e1 :i* d]ives its "n f ! ,lat9 calix1 mean+ 8lime10 may be firm & compact or loose & p[d]y4 ,x is also commonly f\nd mix$ ) o!r mat]ials su* z clay1 s&1 or gravel4 ,cali*e commonly occurs 9 ! ,trans-,pecos1 s\?we/]n ,gulf ,coa/al ,pla91 & ! ,high ,pla9s area ( ,texas 7see fig4 #e1 p4 #h74 ,9 ! latt] area x typically makes up ! 8caprock40 ,cali*e is commonly qu>ri$ 9 ^! p>ts ( ,texas :]e x is us$ z road mat]ial & z an aggregate4 ,good exposures ( ,ogallala cali*e c be se5 on ! surface ar\nd ! ov]look at ,coronado ,lodge on ! nor?we/ rim ( ! canyon 7fig4 #ag74 ,ogallala /rata also crop out along ! upp] rea*es ( ,p>k ,road #e z x />ts to desc5d into ! canyon4 ,b probably ! mo/ spectacul> exposures ( ! ,ogallala are expos$ 9 ! precipit\s face ( ! ,=tress ,cliff 7fig4 #cc7 :i* =ms "p ( ! ea/]n rim ( ! canyon4 ,also locat$ )9 ! ,ogallala ,=mation is a v important aquif]--a por\s1 wat]-be>+ rock =mation4 ,?is f9e-to co>se-gra9$ s&/one is v por\s & p]meable & is ! mo/ important s+le wat]-produc+ =mation 9 ! ,panh&le-,pla9s area4 ,illu/ration3 ,fig4 #ag4 ,! :ite surface 9 ! "r =egr\nd consi/s ( cali*e 7p4 #bf7 9 ! ,ogallala ,=mation4 ,coronado ,lodge c be se5 9 ! "r backgr\nd4 ,opal & *]t are locally abundant 9 ! ,ogallala conglom]ates4 ,! opal1 :i* is f\nd 9 small cavities 9 ! conglom]ate is n ( ! gem v>iety b x does fluoresce4 ,m9]als t exhibit fluoresc5ce emit visible colors :5 expos$ to ultraviolet light4 ,= ?is reason1 ! ,ogallala opal is s\ght aft] by rock & m9]al collectors4 ,! *]t1 a fl9t-l v>iety ( qu>tz1 occurs z nodules 9 ! conglom]ate & 9 a well-develop$ lay] ne> ! base ( ! =mation4 ,bo? ( ^! silice\s 7silica-be>+7 rocks 7 app>5tly priz$ by ! ,indians1 :o us$ !m to fa%ion knives1 scrap]s1 projectile po9ts1 & o!r artifacts4 ,! ,indians also le>n$ t flat slabs ( cali*e 7 ideal = l9+ fireplaces & to con/ruct primitive rock %elt]s4 ,a numb] ( ,plioc5e v]tebrates h be5 f\nd 9 ! ,palo ,duro area4 ,kn[n z ! 8,age ( ,mammals10 ! ,t]ti>y ,p]iod 0 *>act]iz$ by mammals z div]se z 7 ! reptiles ( ! ,mesozoic ,era4 ,among ^! unusual creatures 7 su* n[-ext9ct species z ! sab]-too? cat & ! elephant-l %ovel-jaw$ ma/odon 7fig4 #ah74 ,! rema9s ( ^! z well z bones ( giraffe-l camels1 pony-siz$ horses1 & slo?s h be5 f\nd 9 ! vic9ity ( ! canyon4 ,! grassy pla9s ( ,plioc5e "t 7 also inhabit$ by l>ge tortoises :i* rea*$ l5g?s ( up to #c feet 7fig4 #ai74 ,dioramas %[+ h[ ^! animals might h look$1 z well z _! actual rema9s1 are on display 9 ! ,hall ( ,pre-,hi/ory 9 ! l[] floor ( ! ,panh&le-,pla9s ,hi/orical ,museum 9 ,canyon1 #ac miles we/ ( ! p>k 7p4 #ce74 ,illu/ration3 ,fig4 #ah4 ,?is life-size model ( a %ovel-jaw$ ma/odon is typical ( ! n[-ext9ct1 elephant-l creatures t liv$ 9 ?is area dur+ ! ,plioc5e ,epo*4 7,photograph c\rtesy ,panh&le-,pla9s ,hi/orical ,museum47 ,illu/ration3 ,fig4 #ai4 ,! c>apaces ( giant tortoises z mu* z #c feet long h be5 collect$ f ,plioc5e rocks 9 ! ,palo ,duro area4 7,photograph c\rtesy ,panh&le-,pla9s ,hi/orical ,museum47 ,rocks ( ! ,plei/oc5e4-- ,! y\nge/ rocks 9 ,palo ,duro ,canyon ,/ate ,p>k 7 =m$ dur+ ! ,plei/oc5e ,epo* ( ! ,quat]n>y ,p]iod ( ! ,c5ozoic ,era 7see geologic "t scale1 p4 #aa74 ,plei/oc5e rocks are r widespread 9 mu* ( ! ,panh&le-,pla9s area & !y are mo/ly compos$ ( s$im5ts :i* 7 deposit$ 9 /ream valleys1 9 lakes or ponds1 or by ! w9d4 ,mo/ ( ! ,plei/oc5e /rata 9 ! p>k area consi/ ( loose deposits ( silt & s& :i* 7 deposit$ by w9d action4 ,kn[n locally z 8bl[ s&10 ?is r$di%-br[n1 silty s& ov]lies ! ,ogallala cali*e at mo/ po9ts along ! canyon's rim4 ,,h[ ,,! ,,canyon ,,0 ,,c>v$ ,! visitor see+ ,palo ,duro ,canyon = ! fir/ "t may f9d x difficult to believe t ?is yawn+ *asm began z a simple gully4 ,b to ! geomorphologi/--! geologi/ :o /udies ! orig9 & developm5t ( l&scapes--,palo ,duro ,canyon is b a gully magnifi$ _m times ov]4 ,?is is evid5t because ! %ape ( ! canyon1 ! nature ( its tribut>ies1 & ! "* ( its walls indicate t x has be5 deep5$ & l5g!n$ by ! d[ncutt+ ( a /ream & wid5$ by o!r geologic processes4 ,,! ,,geologic ,,"w ,,( ,,runn+ ,,wat] ,palo ,duro ,canyon is a classic example ( a l&-=m t has be5 creat$ by ! geologic "w ( runn+ wat]4 ,und\bt$ly ! mo/ important s+le ag5t ( erosion1 runn+ wat] probably does m to we> away ! l& ?an all ! o!r geologic ag5ts comb9$4 ,?is is n surpris+ consid]+ ! fact t ! e>?'s annual precipitation 7su* z ra9 & sn[7 equals ab\t f\r billion tons ( wat]4 ,al?\gh ! am\nt ( precipitation v>ies greatly f place to place1 ! av]age annual precipitation on l& is ab\t #dj in*es ( wat]4 ,( ?is1 r\ghly #be p]c5t runs (f f ! l& to =m /reams4 ,:5 "o drives ?r\gh ! p>k & =ds ! normally g5tly fl[+ wat]s ( ! ,prairie ,dog ,t[n ,=k ( ! ,r$ ,riv] he may well wond] if ?is unimpos+ /ream actually is ! geologic ag5t t is responsible = ?is deep gorge4 ,b ! visitor :o happ5s to be pres5t dur+ a sev]e ra9/orm w soon be conv9c$1 = dur+ heavy ra9s ?is g5tle /ream becomes a rag+ torr5t4 ,z ! riv] increases 9 size x also becomes a m effective l&-%ap+ tool1 = ! l>g] & swift] ! /ream1 ! m rock mat]ial x c c>ry4 ,?us1 :5 fl[+ at peak capacity1 ?is bran* ( ! ,r$ ,riv] becomes a mov+ ribbon ( s&pap] ^: load ( s&1 silt1 & gravel has cut & sc\r$ ! canyon walls & floor = hundr$s ( ?\s&s ( ye>s4 ,h[ long has x tak5 ! riv] to c>ve ?is rem>kable *asm8 ,al?\gh !re is no way ( kn[+ = sure1 geologic evid5ce indicates t ! canyon has =m$ dur+ ! la/ "o million ye>s--a relatively %ort "t1 geologically speak+4 ,! "w ( ! riv] is made /ill m effective by wat] & s$im5t :i* x receives f its tribut>ies2 ?is add$ wat] sub/antially increases ! volume & velocity ( ! riv]4 ,al?\gh _m ( ! tribut>y /reams are dry ?r\gh\t mu* ( ! ye>1 !y c>ry l>ge quantities ( wat] dur+ heavy ra9s4 ,moreov]1 because mo/ ( ^! /reams fl[ ov] rock surfaces :i* are n protect$ by ?ick soil or vegetation1 _! wat]s are quickly transport$ to ! ma/] /ream4 ,?us1 ! volume & velocity ( ! ,prairie ,dog ,t[n ,=k ( ! ,r$ ,riv] make x possible--especially dur+ flood p]iods--= ! riv] to c>ry a l>ge load ( rock p>ticles :i* effectively erodes ! /ream *annel4 ,:]e does ?is rock debris come f8 ,mo/ ( x is erod$ f ! sides & bottom ( ! riv]'s *annel4 ,! riv] c>ries its load 9 a numb] ( ways4 ,mat]ial su* z salt & o!r soluble matt] is transport$ 9 a dissolv$ /ate or 9 solution4 ,/ill m1 = example1 silt & f9e s&1 is c>ri$ 9 susp5sion4 ,^! s$im5ts are susp5d$ betwe5 ! surface ( ! wat] & ! bottom ( ! /ream *annel4 ,^? p>ticles t w n dissolve 9 wat] & are too heavy to be c>ri$ 9 susp5sion1 con/itute ! bottom load ( ! /ream4 ,^! l>g] s$im5ts1 su* z gravel1 cobbles1 & b\ld]s1 roll1 b\nce1 or slide along ! /ream b$4 ,z fla% floods c\rse ?r\gh ,palo ,duro ,canyon1 ! riv] uses its load to erode fur!r ! rocks ov] :i* x passes4 ,ea* mov+ rock fragm5t lit]ally becomes a cutt+ tool = abrasion z ! loose rock p>ticles sl[ly we> away ! banks & b$ ( ! /ream4 ,ev5tually ! abrad$ rock fragm5ts become smoo? & r\nd$ & ! /ream *annel is gradually worn d[n to a l[] level2 x is also wid5$4 ,! riv] also erodes by hydraulic action z loose rock fragm5ts are lift$ & mov$ by ! =ce ( ! /ream's curr5t4 ,?is process is simil> to ! effect produc$ :5 soil is *urn$ up & wa%$ away :5 wat] f a g>d5 hose is spray$ on loose e>?4 ,! effects ( hydraulic action h play$ an important role 9 wid5+ ! canyon1 = recession ( ! cliffs away f ! middle ( ! canyons has be5 caus$ 9 "p by und]cutt+4 ,?us1 z ! s(t %ale & gypsum b$s 7 remov$ by ! /ream1 ! ov]ly+ s&/one =mations gradually broke (f & fell into ! canyon4 ,once on ! canyon floor1 mo/ ( ! slabs & blocks ( s&/one 7 ev5tually brok5 up & c>ri$ away by ! /reams z s& & mud4 ,n all ( ! b\ld]s h be5 de/roy$ 9 ?is mann]2 9 places 7= example1 ! ,rock ,g>d57 simil> b\ld]s are se5 today 7fig4 #cd74 ,,wea!r+ ,,& ,,gravity ,,add ,,! ,,f9al ,,t\* ,mo/ ( ! en]gy ( ! riv] has be5 exp5d$ 9 d[ncutt+1 = ! canyon has app>5tly be5 deep5$ m rapidly ?an x has be5 wid5$4 ,b z ! /ream g\g$ its *annel deep] into ! b$rock1 an ev]-increas+ expanse ( canyon wall 0 expos$ to o!r ag5ts ( erosion4 ,sl[ly--almo/ imp]ceptibly--! walls ( ! canyon h be5 erod$ by ! processes ( wea!r+ & mass-wa/+4 ,wea!r+4-- ,:]ev] rocks are expos$ on ! e>?'s surface1 !y are attack$ by ! ag5ts ( wea!r+4 ,!y are dissolv$ by ra9wat]1 pri$ ap>t by fro/ & ice1 & bla/$ by w9dbl[n s&4 ,"s ( ! *anges produc$ by wea!r+ are purely me*anical1 t is1 ! rock is simply r$uc$ to small] fragm5ts )\t be+ brok5 d[n *emically or und]go+ any *ange 9 its m9]al composition4 ,?is me*anical wea!r+1 or dis9tegration1 takes place 9 a numb] ( ways4 ,*anges are especially noticeable 9 rocks t are subject$ to l>ge daily temp]ature v>iations4 ,if a crack 9 ^! rocks becomes fill$ ) wat] & ! temp]ature drops bel[ freez+1 ice =ms4 ,:5 wat] freezes x exp&s by ab\t #aj p]c5t ( its volume--?is is ! reason :y wat] pipes (t5 split op5 dur+ ! w9t]4 ,j z 9 a wat] pipe1 ! pressure ( ! exp&+ ice is commonly great en\gh to wid5 & deep5 ! crack 9 ! rock4 ,?is process1 call$ fro/ w$g+1 may ultimately cause ! rock to split & fall ap>t4 ,! cumulative effects ( fro/ w$g+ h probably play$ a significant role 9 pry+ (f l>ge blocks ( rocks f ! walls & rim ( ! canyon4 ,animals & plants may also ha/5 rock dis9tegration4 ,plant roots commonly gr[ 9 rock crevices & z ! roots become l>g] !y w$ge ! rock ap>t4 ,burr[+ animals su* z rabbits1 goph]s1 & gr\nd squirrels also promote rock dis9tegration4 ,al?\gh !y d n attack ! rocks directly1 _! digg+ exposes new rock surfaces to wea!r+ processes4 ,! holes ^! creatures make also p]mit wat] & air to ent] ! e>? m easily1 !reby ha/5+ rock de/ruction4 ,man1 ( c\rse1 promotes m rock dis9tegration ?an all o!r animals comb9$4 ,?us1 z "o explores ! canyon's trails & climbs its walls1 he w n only see evid5ce ( ! v>i\s types ( me*anical wea!r+1 he w also be contribut+ to ! fur!r we>+ away ( ! rocks4 ,decomposition1 or *emical wea!r+1 works h& 9 h& ) me*anical wea!r+4 ,b unlike dis9tegration1 decomposition produces rock mat]ials t are basically diff]5t f ! orig9al unwea!r$ rock4 ,^! *anges are br\ght ab\t z ! result ( *emical reactions betwe5 m9]als 9 ! rocks & wat]1 c>bon dioxide1 & oxyg54 ,al?\gh ! arid climate & sev]e w9t]s ( ! ,panh&le g5]ally facilitate me*anical wea!r+1 "s ( ! r$ %ales & gypsum deposits %[ ! effect ( oxidation1 hydration1 & o!r =ms ( *emical wea!r+ 7fig4 #aj74 ,mass-wa/+4-- ,mass-wa/+1 ! erosional process by :i* rock & soil move d[nslope 9 response to ! =ce ( gravity1 has also be5 in/rum5tal 9 %ap+ ,palo ,duro ,canyon4 ,?is type ( erosion has be5 especially active on ! walls ( ! canyon1 = "h ! slopes are /eep en\gh to promote d[nw>d movem5t ( e>? mat]ials4 ,9 a few places !re h be5 l&slides :i* h mov$ l>ge quantities ( rock 9 a %ort span ( "t4 ,b mo/ mass movem5ts h be5 imp]ceptibly sl[ z masses ( talus 7accumulations ( rock debris7 on /eep] slopes h in*$ sl[ly d[nhill because ( _! own weight4 ,talus deposits produc$ 9 ?is way c be se5 at ! foot ( mo/ ( ! cliffs & erosional remnants ?r\gh\t ! canyon 7fig4 #bj74 ,diff]5tial erosion4-- ,ev5 ! mo/ casual obs]v] w soon note t n all ( ! canyon's rocks h be5 equally affect$ by erosion4 ,inde$1 x is ! nature ( ?is diff]5tial erosion t gives ,palo ,duro ,canyon ! rugg$ sculptur$ appe>ance t acc\nts = mu* ( its beauty4 ,visitors to ,palo ,duro ,canyon commonly ask :y ! rock =mations are s div]sely %ap$4 ,! answ] to ?is "q lies 9 ! rocks !mselves4 ,because ! v>i\s rock /rata are ( unequal h>dness1 !y erode at diff]5t rates ( spe$4 ,h5ce1 ! h>d]1 m resi/ant rocks1 su* z ! s&/ones & conglom]ates ( ! ,trujillo ,=mation1 =m ! %elves1 l$ges1 & 8caps0 ( ! rock sculptures4 ,! ,ligh?\se 7fig4 #ca7 & o!r p$e/al rocks 7fig4 #af7 are good examples ( l&-=ms produc$ by diff]5tial erosion4 ,! 8hoodoos0 m5tion$ e>li] are also ! products ( ?is type ( erosion 7figs4 #af & #bj74 ,illu/ration3 ,fig4 #bj4 ,talus slopes 7arr[7 are well develop$ on ! ea/ side ( ,capitol ,peak & 9 places obscure ! ,qu>t]ma/] r$ b$s4 ,note ! 8hoodoo0 at ! s\? 7left7 end ( ! /ructure4 ,s(t] rocks l %ales & clay are m readily erod$ & !y normally =m slopes r ?an cliffs or l$ges 7fig4 #ab74 ,grooves1 recesses1 & caves h also develop$ 9 "s ( ! less resi/ant rocks su* z ! %ales & gypsum b$s ( ! ,qu>t]ma/] ,=mation4 ,cat>9a ,cave 7fig4 #bg7 :i* has =m$ 9 ! r$ & :ite %ales ( ! ,spani% ,skirts 7fig4 #bf7 is a good example ( ?is type ( feature4 ,caves ( ?is type af=d$ protection to bo? man & wild animals s9ce ! dawn ( hi/ory1 = _! rema9s h be5 f\nd 9 a numb] ( simil> caves4 ,?us1 )9 a relatively %ort "t--geologically speak+--! famili> l&-%ap+ processes describ$ above h jo9$ =ces to provide ,texas ) "o ( its mo/ rem>kable natural attractions4 ,b int]e/+ly en\gh1 ! same geologic processes t creat$ ^! unusual =mations are busily at "w de/roy+ !m4 ,z "t passes & erosion progresses1 ! caps ( ! p$e/als are worn away & ! und]ly+ %ales crumble & are wa%$ into ! valley bel[4 ,yet ev5 z ! old l&-=ms are be+ de/roy$1 w9d1 wat]1 ice1 & man are attack+ ! canyon walls to produce /ill m ( ^! int]e/+ erosional remnants4 ,,:at ,,to ,,d ,,& ,,see ,,at ,,palo ,,duro ,,canyon ,,/ate ,,p>k ,! visitor to ,palo ,duro ,canyon c *oose f a numb] ( recreational & educational activities4 ,moreov]1 reg>dless ( :e!r "o visits = a few h\rs to picnic along ! banks ( ! riv]1 or sp5ds a week at "o ( ! well-kept campgr\nds1 ! visit w probably be bo? pleasant & rew>d+4 ,9 ! pages t foll[ !re is a brief description ( c]ta9 ( ! p>k l&m>ks & "s ( ! m popul> attractions )9 ! canyon4 ,! numb]s 9 p>5!ses ref] to numb]s :i* designate ^! places on ! map ( ,palo ,duro ,canyon 7fig4 #b1 pp4 #d-e74 ,hopefully1 ?is in=mation w help "o to plan 8 visit to ! canyon & !reby make 8 /ay m enjoyable & wor?:ile4 ,p>k ,entrance 7#a74-- ,! fir/ /op 9 ! p>k is ! gate at ! rang] /ation 7fig4 #ba74 ,"h "o pays a mode/ admission fee & receives lit]ature & in=mation ab\t ! p>k4 ,! p>k is op5 e day ( ! ye>1 b ! entrance gates close at sund[n4 ,coronado ,lodge & ,obs]vation ,po9t 7#b74-- ,! ov]look at ,coronado ,lodge 7fig4 #bb71 locat$ ab\t half a mile f ! ,p>k ,entrance1 is a good place to />t "o's visit4 ,situat$ on a l$ge ( ,ogallala cali*e 7p4 #bf71 ! ,lodge is an attractive1 ru/ic /ructure con/ruct$ ( blocks ( ,trujillo s&/one 7p4 #bb74 ,its picture w9d[s & outdoor ov]look provide a mat*less view ( ! canyon & make x possible to become ori5t$ = ! desc5t to ! canyon floor4 ,l>ge1 co9-op]at$ telescopes p]mit close-up views ( di/ant p>ts ( ! canyon1 & !re are museum cases conta9+ objects ( hi/orical & geological int]e/ f ! ,palo ,duro area4 ,if possible "o %\ld visit ! ,coronado ,obs]vation ,po9t m ?an once dur+ ! visit1 pref]ably at diff]5t times ( ! day4 ,because ( %ift+ cl\ds & *ang+ light+ conditions1 ! canyon pres5ts a cont9ually *ang+ panorama f sunrise to sunset4 ,op5 ye>-r\nd1 ! ,lodge (f]s a complete l9e ( s\v5irs1 film1 & camp+ supplies4 ,!re is also a snack b> :]e c(fee1 s&wi*es1 & cold dr9ks c be pur*as$4 ,! ,sc5ic ,drive 7#a-af74-- ,aft] view+ ! canyon f ,coronado ,lodge1 "o %\ld take ! sc5ic drive on ,p>k ,road #e4 ,?is pav$1 all-wea!r road desc5ds ! nor?we/ rim ( ! canyon & cont9ues on to ! turn>\nd at ,c[ ,camp1 a di/ance ( ab\t #h miles4 ,al?\gh ! pres5t sc5ic drive 0 complet$ 9 #aiea1 ! pa? t x foll[s is ess5tially t :i* 0 laid out by ,colonel ,*>les ,goodnight :5 he e/abli%$ ,palo ,duro ran* 9 #ahgf4 ,! road desc5ds to ! canyon floor 9 a s]ies ( well-eng9e]$ turns1 b because x drops "s #hjj feet 9 little m ?an a mile x is wise to use second or l[ ge> on ! desc5t4 ,"o %\ld also obs]ve ! po/$ spe$ limits 7#aj to #bj miles p] h\r7 & keep to ! "r side ( ! road at all times4 ,9 ! #hjj-;foot drop f rim to floor1 ! complete geologic section ( ! canyon is trav]s$1 z "o passes f ! ,plei/oc5e s&s ?r\gh ! ,ogallala1 ,trujillo1 & ,tecovas ,=mations1 be=e rea*+ ! ,qu>t]ma/] ,=mation :i* is expos$ 9 ! canyon floor4 ,ea* ( ^! geologic =mations is discuss$ else:]e 9 ?is publication 7pp4 #af-bh74 ,pione] ,amphi!atre 7#c74-- ,^u rea*+ ! canyon floor1 ,p>k ,road #e flatt5s out & f ?is po9t x is b a %ort di/ance to ! ,pione] ,amphi!atre1 "o ( ! canyon's newe/ & mo/ popul> attractions4 ,"h1 locat$ at ! foot ( a colorful #fjj-;foot cliff1 is a rem>kable #aejj-seat outdoor !atre ( late/ design 7fig4 #bc74 ,ea* ev5+ dur+ a t5-week summ] season1 a symphonic drama portray+ ! hi/ory ( ! ,texas ,panh&le is pres5t$ 9 ! amphi!atre4 ,in=mation ab\t ^! productions c be obta9$ at ! ,p>k ,entrance1 ,coronado ,lodge1 & o!r po9ts )9 ! p>k4 ,illu/ration3 ,fig4 #ba4 ,! entrance gate to ,palo ,duro ,canyon ,/ate ,p>k4 ,illu/ration3 ,fig4 #bb4 ,coronado ,lodge on ! canyon's nor?we/ rim af=ds panoramic views ( ! canyon4 ,sad ,monkey ,tra9 ,ride 7#d74-- ,! ,sad ,monkey ,railroad beg9s--& ends--at ,sad ,monkey1 ,texas1 a small 8community0 t lies at ! foot ( ,triassic ,peak 7fig4 #bd74 ,unlike mo/ m9iature railroads1 ! ,sad ,monkey ,special is n a 8kiddie0 ride4 ,in/ead1 ?is #b-mile j\rney provides an opportunity to get away f ! road = a clos] look at ! geologic =mations expos$ along ! track4 ,!re are especially good views ( ! ,spani% ,skirts 7fig4 #bf71 ,cat>9a ,cave 7fig4 #bg71 & ,triassic ,peak 7fig4 #be74 ,^!1 & o!r features ( geologic int]e/1 are po9t$ out by an exp]i5c$ lectur] :o also pres5ts a brief review ( ! geologic hi/ory ( ! area4 ,triassic ,peak 7#e74-- ,long us$ by ,indians & ran*]s z a ,palo ,duro l&m>k1 ! canyon visitor w f9d ,triassic ,peak to be equally useful z a geologic l&m>k4 ,:5 view$ f ! ,sad ,monkey ,railroad ,t]m9al1 ! s\? face ( ,triassic ,peak cle>ly reveals ?ree ( ! f\r major geologic =mations ( ! canyon 7fig4 #be74 ,illu/ration3 ,fig4 #bc4 ,locat$ on ! canyon floor1 ,pione] ,amphi!atre is a mod]n outdoor !atre :]e symphonic dramas are pres5t$ ea* summ]4 7,c\rtesy ,mrs4 ,ples ,h>p]1 ,texas ,panh&le ,h]itage ,f\ndation1 ,inc42 photograph by ,ron ,horn47 ,! l[] "o-?ird ( ! peak consi/s ( deeply furr[$1 r$ & :ite b&$ %ales ( ! ,qu>t]ma/] ,=mation 7p4 #ag74 ,ov]ly+ ! ,p]mian r$ b$s are ! brightly color$1 multi-hu$ ,tecovas %ales ( ,triassic age 7p4 #ai74 ,! composition ( ! ,tecovas is su* t ! l[] %ales t5d to wea!r into relatively g5tle slopes ) r smoo? surfaces4 ,triassic ,peak is capp$ by a wea!r-resi/ant lay] ( ,trujillo s&/one1 & ?is durable cliff-=m+ s&/one has s]v$ z a protective cov]+ to imp$e ! erosion ( ! s(t] rocks ( ! ,tecovas & ,qu>t]ma/] ,=mations4 ,al?\gh x has )/ood ! ravages ( "t exce$+ly well1 ! l>ge blocks ( ,trujillo s&/one :i* litt] ! flanks & foot ( ,triassic ,peak cle>ly indicate t wea!r+ & mass-wa/+ h exact$ _! toll 9 ! geologic pa/4 ,illu/ration3 ,fig4 #bd4 ,a trip on ! ,sad ,monkey ,railroad is a good place to le>n m ab\t ! canyon's geology & get a clos] look at ! rocks4 ,illu/ration3 ,fig4 #be4 ,excell5t exposures ( ! ,qu>t]ma/] ,=mation ( ,p]mian age 7#a7 & ! ,triassic ,tecovas 7#b7 & ,trujillo 7#c7 ,=mations c be se5 9 ! s\? face ( ,triassic ,peak4 ,! feature kn[n z ! ,sad ,monkey is indicat$ by ! arr[4 ,sad ,monkey1 ,texas d]ives its "n f ! prom95t mass ( ,trujillo s&/one at ! s\!rn extremity ( ,triassic ,peak4 ,:5 view$ 9 ! prop] p]spective--& ) ! prop] am\nt ( imag9ation--?is massive block ( s&/one be>s a /rik+ resemblance to an ag$ & sadd5$ monkey4 ,spani% ,skirts 7#f74-- ,few ( ! canyon's features are z well-nam$ z ! gaudy ,spani% ,skirts 7fig4 #bf74 ,! l[] "p ( ?is multi-color$ bluff consi/s ( alt]nat+ lay]s ( r$ & :ite ,qu>t]ma/] %ale1 capp$ by ! colorful m>oon & lav5d] ,tecovas %ales4 ,locat$ on ! nor? flank ( ,timb] ,mesa1 ! ,spani% ,skirts & ne>by ,cat>9a ,cave c be rea*$ by an easy half-mile pa?4 ,! trail beg9s on ! we/ side ( ,p>k ,road #e1 j beyond ! ,timb] ,creek bridge locat$ sev]al hundr$ feet f ! ,sad ,monkey ,/ation4 ,cat>9a ,cave 7#g74-- ,a %ort di/ance we/ ( ! ,spani% ,skirts lies ,cat>9a ,cave4 ,?is depression has be5 wa%$ out ( ! relatively soluble ,p]mian %ales 7fig4 #bg74 ,santana's ,face 7#h74-- ,l ,triassic ,peak1 ,timb] ,mesa is capp$ by a ?ick lay] ( massively b$d$ ,trujillo s&/one4 ,on ! ea/]n tip ( ! mesa ! s&/one has be5 erod$ 9 su* a fa%ion t x resembles ! pr(ile ( an ,indian 7fig4 #bh74 ,?is feature1 call$ ,santana's ,face1 is be/ se5 f ! p>k road %ortly aft] leav+ ,sad ,monkey ,/ation4 ,illu/ration3 ,fig4 #bf4 ,! gaudy ,spani% ,skirts are a colorful expanse ( ,qu>t]ma/] & ,tecovas /rata expos$ on ! nor? flank ( ,timb] ,mesa4 ,note ! contra/ 9 wea!r+ 9 ! l[]1 gulli$ ,qu>t]ma/] ,=mation & ! smoo? slopes ( ! ,tecovas %ales above x4 ,cat>9a ,cave 7arr[7 is at ! "r4 ,! ,sky ,ride 7#i74-- ,! ,sky ,ride1 locat$ ne> ! fir/ wat] cross+ on ,p>k ,road #e1 transports visitors f ! canyon floor to ! top ( ,timb] ,mesa 7fig4 #bh74 ,! #cjj-;foot asc5t is made 9 ski-lift *airs t are com=table & safe4 ,! obs]vation area atop ! mesa (f]s an unusually f9e view ( mo/ p>ts ( ! canyon4 ,illu/ration3 ,fig4 #bg4 ,cat>9a ,cave 7arr[7 is easily rea*$ by a half-mile trail f ,p>k ,road #e4 ,illu/ration3 ,fig4 #bh4 ,santana's ,face 7left arr[7 has be5 sculptur$ f ! ,trujillo s&/one cap ( ,timb] ,mesa4 ,! cable = ! ,sky ,ride 7p4 #cg7 passes ?r\gh ! not* indicat$ by arr[ at "r4 ,! ,fir/ ,wat] ,cross+ 7#aj74-- ,z x w9ds ?r\gh ! canyon1 ! p>k road crosses ! ,prairie ,dog ,t[n ,=k ( ! ,r$ ,riv] sev5 times 9 a di/ance ( ab\t #d miles4 ,^! =ds1 or wat] cross+s z !y are call$ locally1 are pav$ & are normally safe to pass ?r\gh4 ,!y %\ld1 h[ev]1 be avoid$ dur+ times ( heavy ra9s & fla% flood+4 ,because ( /ream erosion1 especially f9e exposures ( ! ,qu>t]ma/] ,=mation are reveal$ 9 ! /ream banks ne> sev]al ( ! cross+s4 ,! fir/ ( ^! cross+s 7fig4 #bi7 is ab\t #a mile f ! ,sad ,monkey ,/ation & is "o ( ! m popul> picnic areas 9 ! p>k4 ,?is area 0 also popul> ) e>li] resid5ts ( ! p>k1 = x is believ$ to h be5 ! campgr\nds ( bo? ! ,ki[a & ,coman*e ,indians4 ,colonel ,*>les ,goodnight's ,dug\t 7#aa74-- ,z m5tion$ e>li] 7p4 #f7 ,colonel ,*>les ,goodnight ent]$ ! canyon 9 #ahgf ) m ?an #af1jjj head ( cattle4 ,al?\gh he lat] e/abli%$ m com=table qu>t]s1 ,col4 ,goodnight fir/ liv$ 9 a primitive dug\t simil> to ! "o %[n 9 figure #cj4 ,a replica ( ?is e>ly %elt] has be5 con/ruct$ ( mud1 /one1 & logs & c be se5 on ! we/ side ( ! p>k road j beyond ! fir/ wat] cross+ 7see fig4 #bi74 ,illu/ration3 ,fig4 #bi4 ,n[ a popul> picnic spot1 ! wood$ area ne> ! fir/ wat] cross+ ?r\gh ! ,prairie ,dog ,t[n ,=k ( ! ,r$ ,riv] 0 a favorite ,indian campgr\nd4 ,! ,ligh?\se 7#ab74-- ,! unpav$ road to ! ,ligh?\se ent]s ,p>k ,road #e ab\t two-t5?s ( a mile beyond ! fir/ wat] cross+4 ,al?\gh consid]$ by _m to be ! canyon's be/-kn[n l&m>k1 ! ,ligh?\se is actually n )9 p>k b\nd>ies4 ,x is locat$ 9 ,little ,sunday ,canyon ab\t #c miles we/ ( ! road & is n easily accessible to ! av]age visitor4 ,l _m ( ! p>k's natural attractions1 ! ,ligh?\se is an erosional remnant ( colorful ,trujillo %ales & s&/ones 7fig4 #ca74 ,a simil> p$e/al rock1 ! ,devil's ,tomb/one1 c be rea*$ by means ( a trail :i* leaves ! ,ligh?\se road & ent]s ,sunday ,canyon4 ,illu/ration3 ,fig4 #cj4 ,:5 ,colonel ,*>les ,goodnight settl$ 9 ! canyon 9 #ahgf he liv$ 9 a primitive dug\t simil> to ! "o %[n "h4 ,capitol ,peak 7#ac74-- ,capitol ,peak 7figs4 #bj & #cb7 is a r impos+ geologic feature t c be se5 f a numb] ( po9ts along ,p>k ,road #e4 ,!re are especially good views 9 ! vic9ity ( ! second wat] cross+ if "o w look to ! we/ ( ! road4 ,j beyond ! cross+ an unimprov$ road leads to ! foot ( ,capitol ,peak4 ,! l[] "p ( ?is feature is compos$ ( ,qu>t]ma/] %ales ( ,p]mian age & ! upp] section consi/s l>gely ( ,triassic ,tecovas %ales4 ,:5 view$ f ! prop] angle1 ! silh\ette ( ,capitol ,peak is ?\ght to resemble ! pro/rate =m ( a human 7fig4 #cb74 ,= ?is reason x has also be5 call$ ! ,sleep+ ,indian4 ,=tress ,cliff 7#ad74-- ,! ,ogallala ,=mation ( ,plioc5e age 7p4 #bc7 =ms ! upp] rim ( ! canyon & is well expos$ 9 impressive ,=tress ,cliff 7fig4 #cc74 ,al?\gh ?is precipit\s cliff dom9ates ! ea/]n rim ( ! canyon along mo/ ( ! sc5ic drive1 especially good views are af=d$ betwe5 ! second & ?ird wat] cross+s4 ,! ,rock ,g>d5 7#ae74-- ,%ortly aft] =d+ ! riv] at ! fif? wat] cross+1 !re is a jumbl$ pile ( b\ld]s on ! we/ side ( ! road 7fig4 #cd74 ,?is accumulation ( ,trujillo s&/one blocks has be5 nam$ ! ,rock ,g>d54 ,_m b\ld]s su* z ^! h accumulat$ on ! floor ( ! canyon 9 ages pa/4 ,h[ev]1 mo/ ( ^! h be5 de/roy$ by wea!r+ & _! fragm5ts remov$ by ! canyon's /reams4 ,! ,devil's ,slide 7#af74-- ,! ,devil's ,slide c be rea*$ by an unimprov$ road t leads s\?we/ f ! sc5ic drive = a di/ance ( ab\t half a mile4 ,compos$ ( upp] ,qu>t]ma/] & l[] ,tecovas %ales1 ! surface ( ?is erod$ spur is lac$ ) _m trails & 8slides0 t h be5 made by previ\s visitors 7fig4 #ce74 ,illu/ration3 ,fig4 #ca4 ,! ,ligh?\se1 an erosional remnant & ! 8tradem>k0 ( ,palo ,duro ,canyon1 exhibits well ! geologic ph5om5on ( diff]5tial erosion 7p4 #ca74 ,! ,turn>\nd 7#ag74-- ,a loop m>ks ! end ( ,p>k ,road #e & ! conclusion ( ! sc5ic drive4 ,locat$ 9 ?is area are a numb] ( f9e camp+ areas1 picnic gr\nds1 ! old /one cottages call$ ! 8,c[ ,cab9s10 & re/ rooms ) %[] facilities 7fig4 #cf74 ,illu/ration3 ,fig4 #cb4 ,! 8dome0 on ,capitol ,peak is a well-kn[n canyon l&m>k4 ,compos$ ( ! ,tecovas & ,qu>t]ma/] ,=mations1 ! pr(ile ( ,capitol ,peak is ref]r$ to z ! ,sleep+ ,indian4 7,! 8,indian's0 head c be se5 9 ! "r backgr\nd47 ,illu/ration3 ,fig4 #cc4 ,=tress ,cliff is a prom95t feature on ! ea/]n rim ( ! canyon4 ,se5 "h are ! precipit\s cliffs develop$ 9 ! ,ogallala cali*e 7p4 #bf7 & ! s&/ones & %ales ( ! ,trujillo ,=mation4 ,illu/ration3 ,fig4 #cd4 ,! ,rock ,g>d5 is a jumbl$ mass ( ,trujillo s&/one b\ld]s t m>k ! site ( an anci5t l&slide4 ,hik+4-- ,!re are a numb] ( e/abli%$ trails = ! visitor :o is int]e/$ 9 hik+4 ,! m popul> trails include ^? to ! ,spani% ,skirts & ,cat>9a ,cave 7p4 #cg71 ! ,devil's ,tomb/one1 ! ,ligh?\se 7p4 #ci71 & ! ,devil's ,slide 7p4 #dj74 ,p>k rang]s w be glad to provide m complete in=mation ab\t ^! & o!r trails )9 ! canyon4 ,horseback rid+4-- ,saddle horses c be r5t$ at ! /ables locat$ ea/ ( ! road ne> ! ,pione] ,amphi!atre4 ,!re are a numb] ( trail rides t c be tak5 on well-tra9$ horses accu/om$ to ! rugg$ t]ra9 ( ! canyon4 ,additional in=mation may be obta9$ f ! att5dants at ! /able4 ,camp+ & picnick+4-- ,an ample numb] ( well-develop$ camp+ & picnic areas are scatt]$ ?r\gh\t ! canyon4 ,mo/ are locat$ adjac5t to or a %ort di/ance f ,p>k ,road #e2 !y are equipp$ ) outdoor fireplaces & tables4 ,runn+ wat]1 re/ rooms1 & %[]s are provid$ 9 c]ta9 areas4 ,campsites are available on a fir/-come fir/-s]v$ basis1 & !re is a #aj-;day limit on ov]night camp+4 ,detail$ in=mation on camp+ regulations & camp+ areas is available f a p>k rang] or at ! ,entrance ,/ation4 ,photography4-- ,palo ,duro ,canyon (f]s _m opportunities = bo? amateur & pr(essional photography4 ,! multi-color$ rock =mations1 erosional l&-=ms1 & plants & animals (f] limitless possibilities to ! creative & imag9ative photograph]4 ,color %ots are especially effective1 b a haze filt] w be helpful :5 photograph+ di/ant objects4 ,morn+ & aft]noon are ! be/ times = picture tak+ z ! mid-day sun is 8flat0 & l5ds little p]spective to ! canyon sc5e4 ,illu/ration3 ,fig4 #ce4 ,! ,devil's ,slide 9 ! s\? end ( ! p>k is an erod$ spur ( ,tecovas %ales4 ,"s ( ! 8slides0 made by visitors are indicat$ by ! arr[4 ,illu/ration3 ,fig4 #cf4 ,outcrops ( ! ,qu>t]ma/] 7#a7 & ,tecovas 7#b7 ,=mations provide a geological backdrop = ?is campsite ne> ! turn>\nd at ! end ( ,p>k ,road #e4 ,,panh&le-,,pla9s ,,hi/orical ,,museum ,illu/ration3 ,fig4 #cg4 ,locat$ on ! campus ( ,we/ ,texas ,/ate ,univ]sity 9 ,canyon1 ! ,panh&le-,pla9s ,hi/orical ,museum has _m exhibits ( hi/orical & geological int]e/ t w enhance "o's visit to ,palo ,duro ,canyon ,/ate ,p>k4 7,c\rtesy ,panh&le-,pla9s ,hi/orical ,museum47 ,! visitor to ,palo ,duro ,canyon ,/ate ,p>k w\ld d well to />t 8 visit at ! ,panh&le-,pla9s ,hi/orical ,museum locat$ on ! campus ( ,we/ ,texas ,/ate ,univ]sity 9 ,canyon 7fig4 #cg74 ,"h all phases ( hi/ory--rec5t1 ar*eologic1 & geologic--are depict$ 9 ! v>i\s halls4 ,9 ! ,hall ( ,pre-,hi/ory are ! fossiliz$ rema9s & recon/ructions ( anci5t animals t 7 entomb$ 9 ! canyon walls z long z #bjj million ye>s ago4 ,else:]e !re are exhibits & dioramas t portray human hi/ory 9 ! ,palo ,duro area4 ,beg9n+ ) ! olde/ kn[n evid5ce ( human occupation ab\t #ab1jjj ye>s ago1 !re is a succession ( displays t tell ! /ory ( man 9 ! ,palo ,duro--,high ,pla9s region4 ,^! exhibits foll[ man f ! e>ly ,indians liv+ 9 /one %elt]s1 to ! horse-us+ nomadic pla9s ,indians :o reli$ heavily on ! great h]ds ( bison & :o f\ght a desp]ate b los+ battle to save _! homel& f invasion by ! :ite man4 ,"h1 too1 is ! /ory ( ! com+ ( ! ,spani% conqui/adores1 ! coman*]os 7see p4 #f71 & ! adv5t ( ! anglican settl]4 ,all are portray$ by means ( artifacts t repres5t ! diff]5t cultures ( ! region's colorful pa/4 ,! major !me ( ! ,museum is ! hi/ory ( ! ,high ,pla9s dur+ ! p]iod ( ! cattle indu/ry ( ! op5 range4 ,"o entire hall is devot$ to ! display ( saddles1 spurs1 l>iats1 b>b$ wire1 br&+ irons1 a *uck wagon1 & a life size model ( a typical c[boy ( ! ,old ,we/4 ,! ,museum also h\ses "o ( ! nation's f9e/ collections ( guns ( ! ,old ,we/1 ! ,old ,_w1 & guns ( today4 ,o!r highlights include scale models depict+ sc5es ( ! ,old ,we/1 exhibits ( typical rooms f pione] homes furni%$ ) furniture ( t era1 a f9e assortm5t ( antique vehicles1 & fam\s collections ( ,we/]n art4 ,! ,panh&le-,pla9s ,hi/orical ,museum is easily rea*$ f any ( ! major highways t pass ?r\gh ,canyon4 ,x is op5 f #i3jj a4m4 to #e3jj p4m4 weekdays & f #b3jj p4m4 to #f3jj p4m4 ,sundays4 ,,select$ ,,ref]5ces#b ,br&1 ,j4 ,p4 7#aief7 ,triassic ,sy/em1 9 ,ea/]n ,llano ,e/acado & adjo9+ ,osage ,pla9s3 ,we/ ,texas ,geol4 ,soc4 & ,lubbock ,geol4 ,soc41 ,guidebook1 ,spr+ ,field ,trip1 ,april #f-g1 #aief1 pp4 #h-i4 ,cumm9s1 ,w4 ,f4 7#ahij7 ,! ,p]mian ( ,texas & its ov]ly+ b$s3 ,texas ,geol4 ,survey #a/ ,ann4 ,rept4 7#ahhi71 pp4 #ahc-aig4 ---- 7#ahic7 ,notes on ! geology ( nor?we/]n ,texas3 ,texas ,geol4 ,survey #d? ,ann4 ,rept4 7#ahib71 pt4 #a1 pp4 #agg-bch4 ,drake1 ,n4 ,f4 7#ahib7 ,/ratigraphy ( ! ,triassic =mations ( nor!a/ ,texas3 ,texas ,geol4 ,survey #crd ,ann4 ,rept4 7#ahia71 pp4 #bbe-bdg4 ,evans1 ,g4 ,l4 7#aidi7 ,upp] ,c5ozoic ( ! ,high ,pla9s3 ,we/ ,texas ,geol4 ,soc4 & ,new ,mexico ,geol4 ,soc41 ,guidebook = ,field ,trip ,no4 #b1 ,novemb] #i1 #aidi1 pp4 #a-i4 99----1 & ,meade1 ,g4 ,e4 7#aide7 ,quat]n>y ( ! ,texas ,high ,pla9s1 9 ,contributions to ,geology1 #aidd3 ,univ4 ,texas ,pub4 #ddja1 pp4 #dhe-ejg4 99,frye1 ,j4 ,c41 & ,leon>d1 ,a4 ,b4 7#aieg7 ,/udies ( ,c5ozoic geology along ea/]n m>g9 ( ,texas ,high ,pla9s1 ,arm/rong to ,h[>d c\nties3 ,univ4 ,texas1 ,bur4 ,econ4 ,geol4 ,rept4 ,inves4 ,no4 #cb1 #fb pp4 99----1 & ---- 7#aiei7 ,correlation ( ! ,ogallala ,=mation 7,neog5e7 9 we/]n ,texas ) type localities 9 ,nebraska3 ,univ4 ,texas1 ,bur4 ,econ4 ,geol4 ,rept4 ,inves4 ,no4 #ci1 #df pp4 99----1 & ---- 7#aifd7 ,relation ( ,ogallala ,=mation to ! s\!rn ,high ,pla9s 9 ,texas3 ,univ4 ,texas1 ,bur4 ,econ4 ,geol4 ,rept4 ,inves4 ,no4 #ea1 #be pp4 99,gir>d1 ,r4 ,m4 7#aiei7 ,bibliography & index ( ,texas geology3 ,univ4 ,texas ,pub4 #eiaj1 #bch pp4 99---- 7#aifd7 ,texas rocks & m9]als3 ,univ4 ,texas1 ,bur4 ,econ4 ,geol4 ,guidebook ,no4 #f1 #aji pp4 ,g\ld1 ,c4 ,n4 7#aijb7 ,! geology & wat] res\rces ( ! ea/]n portion ( ! ,panh&le ( ,texas3 ,u4 ,s4 ,geol4 ,survey ,wat]-,supply ,pap] #aed1 #fd pp4 ---- 7#aijg7 ,! geology & wat] res\rces ( ! we/]n portion ( ! ,panh&le ( ,texas3 ,u4 ,s4 ,geol4 ,survey ,wat]-,supply ,pap] #aia1 #gj pp4 99,mat!ws1 ,w4 ,h41 ,,iii 7#aifj7 ,texas fossils3 ,an amateur collector's h&book3 ,univ4 ,texas1 ,bur4 ,econ4 ,geol4 ,guidebook ,no4 #b1 #abc pp4 99,patton1 ,l4 ,t4 7#aibc7 ,! geology ( ,pott] ,c\nty ,texas3 ,univ4 ,texas ,bull4 #bccj1 #ahj pp4 99,re$1 ,l4 ,c41 & ,longneck]1 ,o4 ,m4 7#aicb7 ,! geology ( ,hemphill ,c\nty1 ,texas3 ,univ4 ,texas ,pub4 #cbca1 #ih pp4 99,sell>ds1 ,e4 ,h41 ,adk9s1 ,w4 ,s41 & ,plumm]1 ,f4 ,b4 7#aicc7 ,! geology ( ,texas1 ,vol4 ,i1 ,/ratigraphy3 ,univ4 ,texas ,bull4 #cbcb 7,augu/ #bb1 #aicb71 #ajjg pp4 ,we/ ,texas ,/ate ,univ]sity ,geological ,society 7#aifd7 ,palo ,duro ,field ,trip ,guidebook3 ,we/ ,texas ,/ate ,univ4 ,geol4 ,soc41 ,canyon1 #ah pp4 ---- 7#aifj7 ,geology ( ,palo ,duro ,canyon ,/ate ,p>k & ! ,panh&le ( ,texas3 ,we/ ,texas ,/ate ,univ4 ,geol4 ,soc41 ,guidebook = #aiff ,,sasgs ,annual ,field ,trip1 ,april #ae-ag1 #aiff1 #eh pp4 ,smi?1 ,a4 ,r4 7#aifg7 ,caves ( ,palo ,duro ,canyon3 ,! ,texas ,cav]1 ,abil5e1 ,texas1 vol4 #ab1 pp4 #ade-adh4 ,,gloss>y ,abrasion--erosion ( rock mat]ial by friction ( solid p>ticles mov$ by wat]1 ice1 w9d1 or gravity4 ,absolute "t--geologic "t measur$ 9 ye>s4 ,comp>e ) relative "t4 ,amphibians--cold-blood$ f\r-foot$ animals :i* h gills 9 y\? & lungs 9 maturity 7e4g41 frog74 ,anhydrite--! m9]al calcium sulfate1 ,ca,s,o4 ,see ,gypsum4 ,anticl9e--an ar*-l fold 9 ! rocks1 ) ! b$s dipp+ 9 opposite directions on ! two sides4 ,aquif]--a wat]-be>+ lay] ( por\s & p]meable rock4 ,aragonite--a =m ( calcium c>bonate 7,ca,c,o74 ,ar*eozoic--! olde/ kn[n geological era2 e>ly ,precambrian4 ,b$d+ plane--! plane ( dem>cation betwe5 two individual rock lay]s or /rata4 ,calcite--a m9]al compos$ ( calcium c>bonate1 ,ca,c,o4 ,cali*e--an accumulation ( calcium c>bonate1 commonly :ite 9 color1 9 ! soil pr(ile4 ,c5ozoic--! late/ era ( geologic "t1 conta9+ ! ,t]ti>y & ,quat]n>y ,p]iods & cont9u+ to ! pres5t "t4 ,*]t--d5se1 h>d rock ( v f9e-gra9$ silica1 usually 9 nodul> =m4 ,?is mat]ial is also call$ fl9t4 ,concretion--a conc5tration1 usually sph]ical1 ( m9]al matt] 9 s$im5t>y rocks1 produc$ by deposits f solution2 x is h>d] ?an ! surr\nd+ rock4 ,conglom]ate--a s$im5t>y rock compos$ ( r\nd$1 wat]-worn gravel1 usually mix$ ) s&1 & cem5t$ toge!r by ano!r m9]al sub/ance4 ,coprolite--! fossiliz$ excrem5t ( animals4 ,eolian--p]ta9+ to ! erosion & ! deposits result+ f w9d action & to s$im5t>y rocks compos$ ( w9d-transport$ mat]ial4 ,epo*--a subdivision ( a geologic p]iod1 su* z ! ,plioc5e ,epo* ( ! ,t]ti>y ,p]iod4 ,era--a major division ( geologic "t4 ,all geologic "t is divid$ into five eras3 ! ,ar*eozoic1 ,prot]ozoic1 ,paleozoic1 ,mesozoic1 & ,c5ozoic ,eras4 ,fluoresc5ce--lum9esc5ce ( a m9]al dur+ exposure to radiation 7su* z f ultraviolet or ,x-rays74 ,fluvial deposit--s$im5t deposit$ by /reams4 ,=mation--a rock unit useful = mapp+ & di/+ui%$ prim>ily on ! basis ( li?ologic "*4 ,fossil--any rema9s or traces ( plants or animals pres]v$ 9 deposits ( a pa/ geologic age4 ,geode--a holl[ /one1 usually l9$ or fill$ ) m9]al matt]4 ,geologic age--! age ( an object z /at$ 9 t]ms ( geologic "t 7e4g41 a ,p5nsylvanian f]n1 ,cretace\s d9osaur74 ,geologic "t--all "t :i* has elaps$ s9ce ! fir/ kn[n rocks 7 =m$ & cont9u+ until rec5t1 or mod]n1 times4 ,geologic "t scale--record ( ! divisions ( e>? hi/ory4 ,gypsum--a m9]al1 hydrat$ calcium sulfate 7,ca,s,o#b;,h,o74 ,see ,anhydrite4 ,hoodoo--a =m produc$ by erosion ( rock4 ,ice age--! ,plei/oc5e ,epo* ( ! ,quat]n>y ,p]iod1 ,c5ozoic ,era2 a "t ( ext5sive glaciation4 ,igne\s rock--rocks :i* h solidifi$ f lava or molt5 rock call$ magma4 ,jo9t--a fracture 9 a rock along :i* !re has be5 no displacem5t on opposite sides ( ! break4 ,jo9t ,sy/em--a s]ies ( two or m sets ( jo9ts pass+ ?r\gh a rock mass & sep>at+ x into blocks ( m or less regul> patt]n4 ,mass-wa/+--erosion caus$ *iefly by gravity4 ,mesozoic--! geologic era betwe5 ! ,paleozoic & ,c5ozoic ,eras2 ! 8,age ( ,reptiles40 ,metamorphic rock--rock =m$ f igne\s or s$im5t>y rocks t h be5 subject$ to great *anges 9 temp]ature1 pressure1 or *emical environm5t4 ,metamorphism--! process :]eby rocks are *ang$ physically by heat1 pressure1 or *emical environm5t into diff]5t k9ds4 ,m9]al--a naturally occurr+ inorganic sub/ance possess+ def9ite *emical & physical prop]ties4 ,nodule--r\nd$ lump ( rock or m9]al4 ,outcrop--! area :]e a p>ticul> rock =mation comes to ! surface4 ,paleontology--! sci5ce :i* deals ) ! /udy ( fossils4 ,paleozoic--t era ( geologic "t foll[+ ! ,prot]ozoic & prec$+ ! ,mesozoic4 ,p]iod--a basic unit ( ! geologic "t scale into :i* ! eras are divid$1 su* z ! ,p5nsylvanian ,p]iod ( ! ,paleozoic ,era4 ,p]mian--! sev5? & la/ p]iod ( ! ,paleozoic ,era4 ,plei/oc5e--! fir/ ( ! two epo*s ( ! ,quat]n>y ,p]iod1 & t :i* prec$es mod]n "t1 kn[n z ! ,great ,ice ,age4 ,plioc5e--la/ & y\nge/ epo* ( ! ,t]ti>y ,p]iod ( ! ,c5ozoic ,era4 ,prot]ozoic--y\nge/ era ( ! ,precambrian2 foll[s ! ,ar*eozoic ,era & prec$es ! ,cambrian ,p]iod ( ! ,paleozoic ,era4 ,r$ b$s--a g5]al t]m = r$ s&/one1 %ales1 etc41 :i* appe> to *>act]ize arid p]iods 9 ! pa/4 ,ripple m>ks--wave-l corrugations produc$ 9 unconsolidat$ mat]ials by w9d or wat]4 ,rock--any natural aggregate ( m9]al matt]1 usually consi/+ ( a mixture ( two or m m9]als4 ,s&/one--s$im5t>y rock compos$ ( cem5t$ s& gra9s1 usually qu>tz4 ,s$im5t--mat]ial t has be5 deposit$ by settl+ f a transportation ag5t su* z wat] or air4 ,s$im5t>y rock--rocks =m$ by ! accumulation ( s$im5ts4 ,%ale--a s$im5t>y rock =m$ by ! h>d5+ ( mud & clay & usually t5d+ to split into ?9 %eets or lay]s4 ,silica--an oxide ( silicon 7,si,o74 ,silice\s--conta9+ or p]ta9+ to silica4 ,silt--f9e muddy s$im5t consi/+ ( p>ticles int]m$iate 9 size betwe5 clay p>ticles & s& gra9s4 ,silt/one--a v f9e-gra9$ s$im5t>y rock compos$ ( silt gra9s1 & int]m$iate betwe5 %ale & s&/one4 ,/ratifi$ rocks--s$im5t>y rocks2 ^? =m$ 9 b$s1 lay]s1 or /rata4 ,/ratum--an individual lay] ( rock =mation4 7,plural1 /rata47 ,sup]position1 law (--9 an undi/urb$ sequ5ce ( rocks y\ng] b$s ov]lie old] b$s4 ,syncl9e--a tr\gh-l fold 9 ! rocks1 ) ! b$s dipp+ inw>d on ei!r side4 ,see ,anticl9e4 ,talus--a mass ( rock debris commonly on slopes or at ! base ( a /eep m\nta9 or cliff4 ,topography--! configuration ( a l& surface4 ,uncon=mity--a break 9 ! sequ5ce ( rock =mations :i* sep>ates y\ng] /rata f old] ones2 caus$ prim>ily by removal ( old] rocks by erosion be=e ^? ( a lat] sequ5ce 7 laid d[n4 ,wea!r+--any natural process1 me*anical or *emical1 :]eby rocks are dis9tegrat$ or decompos$ into small] p>ticles & ultimately into clay & soil4 ,index ,a abrasion3 #cj ,adair1 ,john3 #f 8,age ( ,mammals03 #bg alaba/]3 #ag anci5t man 9 ,palo ,duro ,canyon3 #c anhydrite3 #ah anticl9es3 #ah ,apa*es3 #a1 #c aquif]3 #bf ,arapahos3 #c ,ar*eozoic rocks3 #ac ,b 8bl[ s&03 #bh bottom load3 #bi ,brazos ,riv]3 #h ,buettn]ia3 #bb1 #bc1 #bd ,c calcite3 #bb cali*e3 #bf camels3 #bg camp+ & picnick+3 #dc ,canyon1 ,texas3 #de ,capitol ,peak3 #a1 #ah1 #ai1 #ca1 #dj1 #db ,c>bonif]\s ,p]iod3 #af ,cat>9a ,cave3 #ai1 #cg1 #ch *emical wea!r+3 #cj *]t3 #bf ,*ey5nes3 #c ,civilian ,cons]vation ,corps3 #h ,colorado ,riv]3 #h coman*]os3 #f1 #df ,coman*es3 #a1 #c concretions3 #bb conglom]ate3 #bd coprolites3 #bb ,coronado1 ,francisco ,vasquez de3 #c ,coronado ,lodge3 #a1 #ba1 #bf1 #cc1 #cd 8,c[ ,cab9s03 #da cross-b$d+3 #ai1 #bj cross-/ratification3 #ai ,d decomposition3 #cj ,devil's ,slide3 #ai1 #dj1 #dd ,devil's ,tomb/one3 #dj diff]5tial erosion3 #ca1 #da dis9tegration3 #cj dug\t1 ,col4 ,*>les ,goodnight's3 #ci1 #dj ,e e>? hi/ory3 #aj-ab ,ea/]n ,caprock ,esc>pm5t3 #h erosion1 diff]5tial3 #ca1 #da ,f fla% floods3 #bi fluoresc5ce3 #bf fluvial s$im5ts3 #bd ,=tress ,cliff3 #a1 #dj1 #db fossils3 #aj fro/ w$g+3 #cj ,g geodes3 #bb geologic column3 #ab geologic "t scale3 #aa1 #ab geomorphologi/3 #bi ,goodnight1 ,colonel ,*>les3 #a1 #ci1 #dj gypsum3 #ag ,h ,h>p]1 ,mrs4 ,ples3 #ce hematite3 #bb ,he/]1 ,w4 ,a43 #a ,high ,pla9s3 #h hik+3 #dc hi/ory ( p>k3 #c-h 8hoodoos03 #bc1 #ca ,horn1 ,ron3 #ce horseback rid+3 #dc horses3 #bg hydration3 #ah1 #ca hydraulic action3 #cj ,i ,ice ,age3 #c igne\s rocks3 #aj ,indian campgr\nd3 #ci ,indians ( ! ,pla9s3 #c ,j ,,ja ,ran*3 #f ,k ,ki[as3 #a1 #c ,l ,ligh?\se1 ,!3 #bc1 #be1 #ci1 #da ,little ,sunday ,canyon3 #ci ,llano ,e/acado3 #h ,m ,mack5zie1 ,colonel ,ranald3 #c mammals3 #bg ,m>cy1 ,capta9 ,r4 ,b43 #f mass-wa/+3 #ca ma/odon1 %ovel-jaw$3 #bg me*anical wea!r+3 #cj metamorphic rocks3 #aj mort> hole3 #be ,o ,obs]vation ,po9t3 #cc ,ogallala ,=mation3 #ba1 #bc-bg1 #db opal3 #bf oxidation3 #ca ,p ,paleozoic ,era3 #ac ,palo ,duro ,canyon ,/ate ,p>k3 #g1 #ad1 #de ,panh&le-,pla9s ,hi/orical ,museum3 #b1 #bg1 #de-df ,p>k ,entrance3 #cc p>k hi/ory3 #c-h ,p>k ,road #e3 #cc1 #ch1 #ej ,p>k]1 ,*ief ,quanah3 #g ,pecos ,riv]3 #h p$e/al rock3 #be petrifi$ wood3 #bb photography3 #dc phytosaurs3 #bb picnick+ & camp+3 #dc ,pione] ,amphi!atre3 #cc-cd ,pla9s ,indians3 #c ,plei/oc5e rocks3 #bh "t3 #c ,plioc5e ,epo*3 #bg ,prairie ,dog ,t[n ,=k ( ! ,r$ ,riv]3 #a1 #bi1 #ci ,precambrian rocks3 #ac pr9ciple ( sup]position3 #ac ,prot]ozoic rocks3 #ac psilomelane3 #bb ,q ,qu>t]ma/] ,=mation3 #ab1 #ag-ai1 #bj1 #ba1 #ca1 #cf1 #cg1 #db1 #dd ,r ,r$ ,riv]3 #h1 #bi r$uction halos3 #ai1 #bj ripple m>ks3 #ai ,rock ,g>d51 ,!3 #bc1 #dj1 #dc ,rocky ,m\nta9s3 #bd ,s sab]-too? cat3 #bg ,sad ,monkey1 ,texas3 #cf ,railroad3 #f1 #bj1 #bc1 #ce ,santana's ,face3 #bc1 #cg1 #ch sat9 sp>3 #ag ,sc5ic ,drive1 ,!3 #cc s$im5t>y rocks3 #aj s$im5ts3 #aj sel5ite3 #ag sept>ia3 #bb sept>ian concretions3 #bb %ovel-jaw$ ma/odon3 #bg ,sky ,ride1 ,!3 #cg ,sleep+ ,indian3 #dj1 #db slo?s3 #bg silice\s rocks3 #bg solution3 #bi ,spani% ,skirts3 #ai1 #cg suffosian3 #ai ,sunday ,canyon3 #dj sup]position1 pr9ciple (3 #ac susp5sion3 #bi syncl9es3 #ah ,t talus3 #ca talus slopes3 #ca ,tecovas ,=mation3 #ai-bb1 #cf1 #cg1 #db1 #dd ,texas ,panh&le3 #i ,texas ,panh&le ,h]itage ,f\ndation1 ,inc43 #ce ,texas ,p>ks & ,wildlife ,dep>tm5t3 #b ,texas-,santa ,fe ,exp$ition3 #f ,timb] ,mesa3 #a1 #bc1 #cg1 #ch "t scale1 geologic3 #aa1 #ab tortoises3 #bg ,triassic ,peak3 #a1 #ce ,trujillo ,=mation3 #bj1 #ba1 #bb-bc1 #cf1 #ch1 #db1 #dc ,turn>\nd1 ,!3 #a1 #da1 #dd ,u uncon=mities3 #ba ,w wat] cross+s3 #ci wea!r+3 #cj ,we/ ,texas ,/ate ,univ]sity3 #de ,wolf91 ,*>les ,a43 #a ,footnotes #a,pr(essor ( ,geology1 ,lam> ,/ate ,college ( ,te*nology1 ,beaumont1 ,texas4 #b;,entries m>k$ ) a/]isk are publi%$ by ! ,bureau ( ,economic ,geology1 ,! ,univ]sity ( ,texas at ,au/94 ,^? n out ( pr9t are di/ribut$ at nom9al sale price2 li/ s5t on reque/4 ,illu/ration3 ,cov] image1 ,a]ial view ( ,palo ,duro ,canyon ,transcrib]'s ,notes --,?is book1 publi%$ )\t copyright notice1 is 9 ! public doma94 --,sil5tly correct$ a few palpable typos4 --,add$ l9ks to gloss>y entries4