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Anticline and Adjacent Areas Grand County, Utah

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Please do not destroy or throw away this publication. If you have no further use for it write to the Geological Survey at Washington and ask for a frank to return it UNITED STATES DEPARTMENT OF THE INTERIOR Harold L. Ickes, Secretary GEOLOGICAL, SURVEY W. C. Mendenhall, Director Bulletin 863 GEOLOGY OF THE SALT VALLEY ANTICLINE AND ADJACENT AREAS GRAND COUNTY, UTAH BY C. H. DANE UNITED STATES GOVERNMENT PRINTING OFFICE WASHINGTON : 1935 For sale by the Superintendent of Documents, Washington, D. C. - - Price $1.00 (Paper cover) CONTENTS Abstract.____________________________________________________ 1 .Introduction____________________________________________ 2 Purpose and scope of the work_____________________________ 2 Field work.____________________________________________________ 4 Acknowledgments....-___--____-___-_--_-______.__________ 5 Topography, drainage, and water supply. ______ 5 Climate_._.__..-.-_--_-______- _ ____ 11 Vegetation. ____________________________ 14 Fuel.._____________________________________ 15 Population, accessibility, routes of travel___--______..________ 15 Previous publications......--.-.-.---.-...__---_-__-___._______ 17 Stratigraphy __ ____.____-__-_---_--____---______--___________.__ 18 Pre-Cambrian complex___---_-_-_-_-_-_-_--__ __--______ 20 Carboniferous system..______--__--_____-_-_-_-_-___-___.______ 24 Pennsylvanian (?) series.__________________________________ 24 Unnamed conglomerate--_______-._____________________ 24 Pennsylvanian series..--____-_-_-_-_-_-______--___.________ 25 Paradox formation.____-_-___---__-_____-__-__-__..__. 25 Hermosa formation..._________________________________ 33 Permian series.___-_-_-_--_-_-_-------___-_-_------___-___ 38 Cutler formation____--___-_-----_-________.___________ 38 Triassic system_____-___-_-_--_______-_-___-_______-__-______.i 42 Lower Triassic 8eries_----__-__--------_-___-_-___--_______ 42 Moenkopi formation._.._____.______.____.___-_____.___ 42 Upper Triassic series_---__-_-_-_----_---_---_-_-_-_---._-_ 54 Chinle formation..____________________________________ 54 Jurassic (?) system.___-____--_______-__-_-_-_--__.____._______ 65 Glen Canyon group--...-. ____-____-_-_-___-_-__-_______ 65 Wingate sandstone.___________-__-____-__-_-.--__-____ 65 Kayenta formation.___________________________________ 76 Navajo sandstone.____________________________________ 83 General relations and age of the Glen Canyon group ______ 88 Jurassic system. __.__-._-_-_---___--_-_-__-___-_-----_--____-__ 89 San Rafael group-.--..-----.-------_--__---_---_---___-.. 89 Carmel formation._-___--__-_-___.-____-----__-_______ 90 Entrada sandstone.___________________________________ 92 Summerville formation...._____._.___.__________1_____ 102 Morrison formation___________-___-_______-_--_-__________ 106 Cretaceous system_______-_____________-_.______--_-----______ 113 Upper Cretaceous series..._________________________________ 113 Dakota (?) sandstone..__._______________-__-_--_--____ 113 Mancos shale--__---___-_->_-_ _____________________ 117 Structure. ______________________..__ . ____ 118 General features.._________-____________--___________---_-_-_- 118 Methods of representing structure_ __-_____. _________ 119 m IV CONTENTS Structure Continued. Page Details of structure______-___-___-__---__--__-----___-_-_____ 121 Salt Valley anticline.__-------_-_-_____---_---_____________ 121 Crescent area_----_~---_---_----_-___-___---_-.._---_-___- 124 Cache Valley graben________-_..___________________________ 125 Elephant Buttefolds__:-----------_-------_---_--__---_--- 126 Yellow Cat dome.-.---------------__--__-___--_____..._ 127 Onion Creek anticline___---__--___--__-_-_-______--______ 127 Cottonwood Canyon graben________________________________ 128 Sagers Wash syncline------------_--_-__..----_---------____ 129 Ryan Creek fault zone-_-_----_---__-------,--_--------_-__- 129 Dry Gulch fault..._.....__.._...___..__.__..___..._.___.._ 130 Sand Flat graben______.__._______________________________ 131 South Cisco anticline..----------.-__-_-___---_-_________ 132 Little Dolores River fault zone__-________-_-___-____-____ 133 Harley anticline________________________________________ 133 Bitter Creek anticline__--_--___-_______-_-______-________ 134 General nature of faults__------__-__--_---_---___-__--__.-_-__ 134 , Age of deformation__________________________________________ 135 Relation of the structure of the area to the regional structure_________ 138 Intrusive relations of the Paradox formation____________________ 138 Physical conditions of flowage of the salt in the Paradox formation _ . _ _ 145 Geologic date of the intrusion of the Paradox formation. _ ____________ 148 Structural history.-_____.--_-----_--__-___-________--_________ 153 Geomorphic history.___-.___._____-__--_______-___-___-__-_.__...__ 155 Economic geology_--__---_-___-------_----__-------___.___________ 158 Oil and gas_________-___--_----_-___-_________-_____________ 158 History of drilling.--..---. -__-_-_---_-__-____-__________ 158 Oil and gas possibilities-___-___---__--_--_______--_________ 172 -< Gypsum, salt, and potash.-.-- ---_-----------_,--_---__-_-___ 175 i Uranium and vanadium ores_______-____-__--__-___.________._ 176 Other metallic minerals.__-_ -_--__- -__--__--_.__---_---_--____ 176 Index ___-__.----- - _- 181 * ILLTJSTKATIONS Pago PLATE 1. Geologic map of the Salt Valley anticline and adjacent areas.-------------------------------------------- In pocket 2. Structure contour map of the Salt Valley anticline and adjacent areas.__________-__--__-_---_-_-_-__---------__-__ In pocket 3. Structure sections along lines indicated on plate l___-___-_ In pocket 4. A, La Sal Mountains, from the south end of Polar Mesa; B, View up the canyon of the Colorado River about 3 miles below Dewey.-------------------.---.---------------- 10 5. East wall of north end of Salt Valley,-._____---__---_.__- 11 6. A, Pre-Cambrian granite north of Ryan Creek; B, Pre- Cambrian gneiss and schist north of Dry Gulch___________ 26 7. A, Paradox formation at west end of Onion Creek mass, showing intrusive contact with Cutler formation; B, Photomicrograph of fine-grained sandstone of the Paradox-formation_______ 27 CONTENTS . .V Page PLATE 8. A, Angular unconformity truncating Cutler sandstone in lower Castle Valley; B, Cliff north of the Colorado River viewed fromNE^sec. 20, T. 24 S.,R. 23 E______________.._._.__. 42 9. A, Chinle shale and overlying Wingate sandstone at Big Hole, Westwater Canyon, Colorado River; B, View down the Dolores River from a point a few miles above Gateway, Colo. 43 10. A, Photomicrograph of Wingate sandstone; B, Characteristic bencn and ledge outcrop of Kayenta formation_.__________ 74 11. A, View looking southeast up Beaver Canyon from a point near the southeast corner of sec. 31, T. 24 S., R. 26 E.; B, White Navajo sandstone, thin-bedded Carmel formation, and over­ lying Eutrada sandstone 5% miles above Moab on road to Thompson ____________________________________________ 75 12. A, View looking southeast from center of sec. 17, T. 23 S., R. 24 E., at cliff of Entrada sandstone; B, Moab sandstone member and underlying beds of Entrada sandstone from Colorado River bottom at Hallet's ranch, near mouth of Agate Wash.. 90 13. A, Photomicrograph of Entrada sandstone; B, Photomicro­ graph of Moab sandstone----______---___-_-__--____-_-_ 91 14. A, Tangential cross-bedding in Entrada sandstone; B, Carmel- Entrada contact a quarter of a mile east of the southeast corner of sec. 13, T. 22 S., R. 24 E___.___________________ 98 15. A, Carmel-Entrada contact a few hundred feet south of the place shown in plate 14, B; B, Faulted bedding in Entrada sandstone southeast of Dewey, near center of sec. 17, T. 23 S., R. 24 E----_-_-_-----------.---____..___--__--_.- 99 16. A, Exposure of Sumrnerville formation in NE/4 sec. 12, T. 22 S., R. 24 E.; B, Variegated clay and sandstone of upper part of Morrison formation in sec. 21, T. 21 S., R. 24 E___________ 106 17. A, Morrison formation on northeast bank of Dolores River in sec. 9, T. 23 S., R. 24 E.; J5, View looking northeast across valley of Ryan Creek from a point about 3 miles west of the Colorado-Utah state line.______________________________ 107 18. A, Fault contact of Entrada sandstone and Morrison formation in SE^ sec. 13, T. 22 S., R. 24 E.; B, Morrison formation dropped against Moab sandstone member of Entrada sand­ stone by the Dry Gulch fault near southeast corner of sec. 27, T. 21 S., R. 24 E_____-----_-_-_-__-__-_______-_______- 130 19. Generalized map of the principal faults and outcrops of the Paradox formation of eastern Utah and western Colorado. __ 138 20. A, Anticlinal fold outlined by cuesta ridge of Dakota(?) sand­ stone; B, Bitter Creek anticline from the Sl&% sec. 1, T. 19 S., R. 25 E__-_______-__-___--__-_______--___--__________ 154 21. Alluvial fill of Fisher Valley dissected by dry washes at the head of Onion Creek_____________.__________________________ 155 FIGURE 1. Index map of Utah showing location of area mapped on plates 1 and 2______________________________________________ 3 2. Cross section of southwest side of Fisher Valley.____________ 36 3. Differential compaction of shale bed at the top of the Chinle formation.____________________________________________ 73 4. North end of small intrusion of Paradox formation in east end ftf^ of Cache Valley.......___._.__.__.____.._.__..________ 140 GEOLOGY OF THE SALT VALLEY ANTICLINE AND ADJACENT AKEAS, GEAND COUNTY, UTAH By C. H. DANE ABSTRACT The area described in this report includes about 800 square miles of semiarid, rugged country in Grand County, Utah, adjacent to the Utah-Colorado State line. Its northern part is crossed by the main line of the Denver & Bio Grande West­ ern Railroad from Denver to Salt Lake City. The area lies near the northern : and eastern margins of the Canyon Lands subdivision of the Colorado Plateau. The oldest exposed rocks, which are of pre-Cambrian age and crop out only in the Uncompahgre Plateau, in the northeastern part of the area, are horn­ blende and biotite gneisses and schists, intruded by a coarse-grained granite.
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