| Show I Possibilities of Oil Oat In Southern Utah Explained By United States Government Exploration Experts j I The Th exploratory campaign for foron on carried on In 1925 1125 In tho Rocky mountains resulted In an 1 outstanding discovery early In December when a II well on the tho Cane Creek dome near Moab Utah began producing oil This discovery ery suggests that In parts ot of the th southeastern astern Utah and southwestern Colorado notable quantities of o oil may be obtained I from the th Pennsylvanian forma forma- formation j lion Uon that now yields oil at it Cane and nd possibly from younger rocks In which oil may have havo ac- ac accumulated ac accumulated cumulated by upward migration Because of these possibilities It ems s-ems worth while to summarize It 16 Lefty the th results ot of a recon recon- recon n study tudy of ot this region that was mss 11 made during the summer ot of 1 5 by W T Lee Le and nd W W Wi I I Boyer of ot the geological ecological survey I department of the th Interior and also lao the th results of o an examina examina- examination t tion on of ot the San Rarael swell by James of o the th survey From information ath led by these Held field studies and from date already trade made available by previous prevIous previous ious geologic investigations In It seems probable that conditions to those recently found near Moab exist at other points In Utah south of tho the Denver Rio No Grando Western estern railroad and cast of Green River liver 01 or cast east ot of the meridian and also In Inthe Inthe Inthe the part of ot Colorado south of ot the tho pla- pla plateau plateau pla plateau SEDIMENTARY RY ROCKS The rocks exposed in south south- southeastern south eastern eastorn Utah and southwestern Colorado that are of ot present In- In interest In Interest terest to the th oil producer range In ao ago from Pennsylvania to to early Upper Cretaceous These rocks have ha been reviewed and described by Cross In volume volum 15 of ot th the Journal Jour Jour- Journal Journal nal of ot Geology and a more recent re- re recent re recent cent and detailed description of the formations has been ghen by Coffin In Bulletin 16 It of ot the Ceo Geo- Geographical Cco graphical survey The Tho facts not nol noted not noted ed cd by Lee and Boyer Boer confirm In I part this earlier work although they suggest a need for the tho moil modi modification of ot some Interpretations The Tho formations now recognized In Inthe Inthe Inthe the area are ar shown In la the tho ac- ac accompanying ac accompanying companying chart and are ar de- de described de described scribed below In order of deposition deposition deposition tion from th the earliest to the lat latest lat lat- latest est PEl ROCKS Hermosa near formation formation near Pico Colo the Hermos formation Is 1800 1500 to 10 2000 feet thick Its It lower part Jart consists of ot black bituminous sit shale ale and aud limestone ne and these beds are arc overlain by 30 feet ot of gypsum and feet of rocks which arc are nowhere exposed to view but which may contain sol sol- soluble sol soluble uble materials such as rock salt saltA A considerable thickness of ot salt gypsum black shalo shale and ston lime lime- limestone limestone stone was penetrated by the th low low- lowel lower low lower er el part of ot the tho Cane Creek well welland and beds of ot salt and gypsum that contain limestone are exposed In the Paradox valley allty and other anticlines or 01 have been penetrated by wells drilled on these folds About feet of salt gypsum and bi- bi bituminous bi bituminous luminous shale are present be- be beneath beneath be beneath neath Paradox valley but this apparent thickness may be b local and abnormal and may have been Induced by flowage of ot these thos plas- plas plastic pIn plas plastic tic beds Some potash occurs occur In Inthe Inthe Inthe the salt beds of the th region and the possibility that commercially valuable quantities of ot potash may maybe maybe maybe be present warrants tho the collection lion tion and testing of samples sample s ot of the salt bearing strata Beds of t Pennsylvanian age yield the oil found near Moab and are arc tentatively regarded as equivalent to part or all of the Hermosa formation of ot southwestern Colorado Colo Colo- Colorado Colorado rado and to the tho lower part of the Goodridge tion forina-tion ot of the San SanJuan SanJuan SanJuan Juan valley as described by Woodruff In Bulletin of ot the al survey Burny Rico and Supai 7 1 7 formations I 1 At Its type locality in southwestern southwestern south- south I western Colorado the Rico for for i of age atre con consists of fe feet t of ot reddish redd sandstones together with some I conglomerates an and thin and resembles resemble In Ini I thickness and nd the th J et it of strata that underlies thoi the tho I sandstone In the tho SanJuan San Juan Junn valley alle which Is tentatively referred by Miser to tb th the Supai formation In the tho upper part of the Goodridge formation predomInantly predominantly red led strata not greatly un un- un unlike un like tho overlying Supai 7 1 con con- contain con contain tam tain r a a fauna and In InthIs inthis Inthis thIs respect rC blo also the tho formation of facts Colorado Colorado which may Indicate that the up- up upper up upper per pcr part of ot the th Goodridge e and po possibly part of ot tho the Supai 7 1 are arc equivalent to tho the Pico formation Beds of Rico Eico age c may be pres pres- present present ent under cover In many places s sIn In southwesters southwestern Colorado ant and southeastern Utah although ap- ap ap apparently they eroded from at least the more pronounced up- up up lifts uplifts such ruch as tho Uncompahgre I plateau Coconino The Th Coconino Co- Co Coconi conino Co-conino I CoI coni conino no sandstone of age is 18 a a conspicuous formation west wc tand and north of the tho San Juan oil oilfield field but It things thing out and la Is I absent at Bluff and Moab In contrast with this decrease In thickness the tho sandstone that forms the th natural brIdges south south- southwest wc fouth-wc west t of ot Monticello and 1 Is 1 possibly equivalent to the th Coconino Is I more mOIo than 1000 feet teet thick near the tho brIdges and Is I about 1000 feet thick near neal the tho mouth of Green river SIO ROCKS Th The rocks of unquestioned Trl- Trl Tri age f In the th San Juan river region ot of o southeastern Utah com com- comprise prise comprise In ascending order arder tho formation conglomerate and Chinle forma forma- tion formation Beds Bed of ot variable appear ante ance and composition that belong to ta the th lower part of the th red bed series serles erie lie II uncomfortably on tho Penn Pennsylvanian rocks that are ar ex- ex ex posed exposed near Moab l These The beds are assigned by Cross Cro s and Coffin to the Cutler and Dolores Dalores forma forma- formations lions The upper part of ot the th con red beds which con con- the Dolores formation as 88 the tho term was applied by Cross near Telluride Is ID correlated con con- confidently wit forma lion of southern Utah and tho the contact of tat U-la U unit with the over over- lying overlying sandstone that formation Is li present fur fur- furnishes ono one of ot the tho most conven conven- lent key horizons l for tracing available In the area here described Tho The correlation of ot the lower part of ot these these hese conglomeratic red beds In which petrified wood and fossil bones and teeth are commonly found Is however un- un uncertain uncertain un uncertain certain though It may Day correspond to the tho conglomerate a- a suggested by Cross Tito Tho Cutler Culler formation at Its lis type locality near Ouray Colorado In- In intervenes In Intervenes ter enes between the tho Dolores andRico andRico and Rico formations and consists In lapart par of red calcareous sandy that may correspond to the beds which are locally exposed In the tho th Moab l re- re region region rc-Clon rc gion Some of ot tho the gypsum beds that overlie the tho th Pennsylvanian near Moab may how how- however however however ever actually belong to the tho Rico formation whereas a part of at them at least least are ar belleve believed to be re- re refer referable re referable fer ble to the Triassic lo Moenkopi formation Possibly the th marino marine gypsum bearing Moenkopi of southern Utah may represent the seaward equivalents of at tho the Cut Cut- Cutler Cut Cutler ler conglomerates RI 1 LB I IN TIO FORR The beds between the tIle Chinle and Hermosa 7 1 formations ot of southeastern Utah are markedly variable In thickness and may be divisible Uv into several formations ono one or more mor of which may haye beep extensively ely eroded during pre Chinle time Nar Near the tho toad road from Valley City to Moab Mob just north of tho the Colorado river the Interval Inter between the th Chinle and the Hermosa Is occupied by feet of conglomerates conglomerate with which are ar some somo sandstones sandstone and flinty The lowest lowet of these conglomerate beds contains fos- fos fos Ill all which resembles re emble that teat t at of af th the Chinle In Lisbon valley alley sim sim- similar simIlar ilar liar beds are 1400 feet teet thick In Salt Salt Valley elgh eight t miles north of Cal Castleton and In Paradox val val- valley val valley ai ley Colorado partial measure measure- me measurements measurements sure sure- ments show respectively 1300 and add 1200 feet of ot conglomeratic beds beneath a bed that appears to be bethe bethe bethe the base baso of ot the Chinle and the conglomerates In Paradox valley y contain fragment of or fossil wood and fossil teeth similar to those In the th Chinle The Tho beds just ju t described form the thO lower part of ot the tho Dolores Dolore and Cutter Cutler beds as mapped In Colo Colo- Colorado Colorado Colorado rado rado- by Coffin Cortin and were tenta- tenta tentatively referred to the Permian by Cross Cros They are designated car car- carboniferous car carboniferous on the geologic map or Utah Ulah published with the geo- geo geological geological eco ecological logical surveys survey's survey professional paper Iq III although fossil bones teeth and wood since found In them suggest that part or all of ot them bo be referred to the sic sic The rocks now tentatively as- as assigned assigned as assigned signed to the tho Jurassic and be- be believed be believed by I- I Ie Lee e Boyer Bayer to be un- un undoubtedly undoubtedly un undoubtedly Jurassic Include In as- as ascending a order the Wingate sand sand- sandstone sandstone sandstone stone the formation a and nil the tho Navajo Na sandstone These for for- formations formil tor mil i ns have hav not yielded lel fossils but they compose a related group of beds that Is I overlain o by beds I I which contain coptain a marine marin fauna faun aura I of Upper Jurassic age Wingate The sandstone sandstone Th Win Win- Wingate cato In gate Is a great making cliff sand sand- sandstone sandstone stone and its Iti It color suggested ues ted the Ibe name Vermilion Cliff Clift sandstone which has been ben applied to It by some geologists It lies lie on the tho Chinle forma forma- formation formation tion and Is the aid oldest est of ot the tho probable probable probable able Jurassic Jur formations formation represented represented In this region In some places where the tho is not recognized the tho Wingate and the tho overlying Navajo sandstone sandston are not clearly separable Over aide Ide areas however where the tho tw two are distinct the Wingate sand sand sand- sandstone stone maintains a con I con con- constant con constant stant thickness It Is cross cross-bedd cross bed ded but less conspicuously so than the Navajo and It usually breaks Into columnar blocks on weathering ering It is about feet thick In southeastern Utah Uta and Is somewhat thinner In castelO eastern Utah where it has been called the upper Dolores sandstone by Cross Cron and others It persists eastward Into the vicinity ot of Grand Junction Colorado where It Is about feet thick but Is absent farther farther south Near Tel Tel- Telluride Tel luride the th basal La Plata Plat or Nav Nav- NavaJo Navajo Navajo ajo sandstone rests on the th conglomeratic beds of o i the Dolores formation which are aro cor- cor correlated correlated cor correlated related with the th Chinle formation In other place places In western estern Colo Colo- Colorado Colorado rado probable representatives ot of the Wingate have hav been included in the Dolores Dolore formation This eastward thinning and fin fin- final final fin final al disappearance of ot the th sandstone may be duo to position or to lateral change chance In character or eo o erosion after the sandstone was laid down At At every exposure that was examined the Wingate sandstone gives place abruptly at Its base baso to the Chinle beds The i contact Is Irregular as if it represented an old surface of erosion erosion This Irregular contact an al an the Irregularity arity larity In thickness of the under under- underlying under lying beds seem eem to Indi- Indi Indicate cato cato cate an unconformity of ot wide wid ex- ex exten extent ex extent ten tent tent tent- lo formation formation The rocks here called the formation consist of at platy red sandstones that contain thin layers layer of ot shale Pebble beds are found In the th for for- formation for formation mation nation In a 11 few tew plates places In south south- southeastern south eastern ea eastern tern Utah the does doe not differ conspicuously from the un- un underlying un WIngate sandstone It IL Is locally absent and Its It maximum observed th thickness ss Is feet Navajo Na The sandstone The Navajo Na Is a colored light colored massive strong strong- strongly ly ly b y cross-bedded cross sandstone It seems to attain attaints Its I ts maximum thickness In south south- southern southern ern Utah where It la Is I about feet thick and It thins toward the north and the east Near NeRr Green River Utah Ulah It Is ls little littlemore littlemore more than feet teet thick In southwestern s Colorado It la Is I less Jess han t feet and farther to the north and east cast it Is still sUll thinner Continued on Following Page e Pit e I POSSIBILITIES OF OIL IN SOUTHERN UTAH EXPLAINED BY UNITED I STATES ENGINEERS e 1 from Page PaC P ff The Navajo sandstone lies flea with apparent conformity l Upon on tho pre ceding beds In the western 10 lo localities o cantles but the thc presence of ot An unconformity beneath It Is la clear clear- clear I 1 evident t In Ito lla more easterly ex- ex exposures cx ures po where It overlaps tho thool thool ol I r r formations finally rests on pre Cambrian If g SIC JUn JUi ROCKS Tho The rocks now assigned with with- without without out question to the Jurassic have haver r nil been divided divided dl Into four formations to which in In InE In reports report by and oth oth- oth rs 3 are applied in ascending or- or or or d lh the names Carmel formation Entrada sandstone CurtI Curtla forma forma- formation formation tion non and Summer formation Thi Th Carmel and Curtis contain faunas of Upper JurassIc a and the Summerville Is so eo closely related to the tile Curtis formation ai as to leave lea l av no room for that It also diso Is of Jurassic lc ae age ace OARMEL o Carmel The formation formation Tho Carmel formation Is of marine origin In Inc InC c Utah in la eastern Utah it consists of red sandy candy shale and bedded thin bedded 1 sandstones with local beds of limestone anti and 1 gypsum cypsum Tho formation In tho the eastern re re-Clon re don glon contains contain unconformities that lie at lit different hoc hor borbons horizons bons In different places and and some porno of the tho strata are markedly crinkled characteristics which aidIn aid aidIn aidin In Identifying tho the formation The Tho Carmel Cannel Is apparently equivalent alent In ar ago age to the tho middle part of the theLa La 11 |
