Geology of the Gore Canyon- Kremmling area, Grand County, Colorado Item Type text; Thesis-Reproduction (electronic) Authors Barclay, C. S. Venable Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 23/09/2021 15:48:22 Link to Item http://hdl.handle.net/10150/347644 GEOLOGY OF THE GORE CANYON-KREMMLING. AREA, GRAND COUNTY, COLORADO by ■ ' . C . S. Venable Barclay A Thesis Submitted to the Faculty of the DEPARTMENT OF GEOLOGY In Partial Fulfillment of the Requirements - For the Degree of MASTER OF SCIENCE In the Graduate College THE UNIVERSITY.OF ARIZONA 19 6 8 STATEMENT BY AUTHOR This thesis has been submitted in partial fulfillment of re­ quirements for an advanced degree at The University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this thesis are allowable without special permission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his judg­ ment the proposed use of the material is in the interests of scholar­ ship. In all other instances, however, permission must be obtained from the author. SIGNED: APPROVAL BY THESIS DIRECTOR This thesis has been approved on the date shown below: EVANS B. MAY/5 7 / y Date Professor of Geology ACKNOWLEDGMENTS The work.for this thesis was done while the author was employed by the U.S. Geological Survey9 and the author is grateful for permis­ sion to use Survey data for a thesis. Fossil determinations were made by W. A. Cobban* R. A. Scott* and J. F. Hello* U.S. Geological Survey* and various chemical analyses of some sedimentary rocks* by K. P. Moore* also of the Survey* and the results of some of their work are incorporated in this report. C. E. Hedge of the U.S. Geological Survey made age determinations on a group of samples collected by the author from a granophyre dike in the Gore Canyon area. W. N. Lockwood of the U.S. Geological Survey used four samples which the author collected from the Niobrara Formation in his research on differential thermal analyses techniques for carbonate* and the results of his determinations are included in this report. Several U.S. Geological Survey geologists visited the area and advised on specific problems. In June 1964* W. J. Hail* Jr.* spent two days with the author studying Mesozoic units which he had mapped to the north. During the same month* R. B. Taylor spent a day with the author studying Precambrian rocks of the area. In June 1963* G. N. Pipiringos of the U.S. Geological Survey spent three days in the Kremmling and adjacent areas as part of his regional study of marine Jurassic rocks and he gave the author considerable aid in understanding the Jurassic and adjacent rocks. iv Special acknowledgment is given to Go ■AQ•Izett of the U.S. Geological -Survey who suggested the area for a thesis and advised the author during the investigatione In 1964, A 0 M, Thompson, at that time field assistant to Izett and a student at Brown University, assisted in the field for three days„ The author is most grateful to Dr. E, Bo Mayo, Professor of Geology at the University of Arizona and faculty advisor for this thesis, who has critically read the manuscript and who has supported this thesis by generous contributions of his time and effort„ The people of the Kremmling area were most helpful; deserving special mention are the Messrs. Yust, De Berard, and Martin, all ranchers of the area, who allowed the author free access to their property. Finally, the author wishes to acknowledge the support rendered by Mrs. C.- So Vo Barclay who typed the first draft of the manuscript. TABLE OF CONTENTS Page LIST OF ILLUSTRATIONS oo o.o o.„ . ix L I S T .OF TABLES . @ . ® . .. .,. x h l i AB STRACT ® © . © . © . © @ © . © © © . © . © . © © sc.L'v INTRODUCTION © © © © © © © © © © © © © . © © © a © © © © © © © © 1 Location9 .Size, and Accessibility © © © © . © © © . © . © © © 1 Present Investigation © © © © . © © © © © , © © © . « © „ © © 3 F i e 1 dx/'/ o r k © © © © © © © © © © © © © © © © © © © . © © © © © © © 3 Laboratory Work . © © . © © © . © © . © © © © © © © © © © . © © 4 Previous Work © © © © © © © . © © © © © © © © © . © © © © © © 4 PHYSIOGRAPHY © © © © © © © © © © © © © © © © © © © © © © © © * © 6 Relief © © © © © © © © © © © © © o-o e-o © © © © © © © © o o 6 Topography © © © © © . © © © © @ - © © ©•© © © © © © © . © © 6 Drainage © © © © © © © © © © © © © .© ©©©.©© . © © © © © © © 7 C 1imat e © © © © © © © . © © © © © © © © © © © © © © © * © © © 7 Vegetation © © © © © © . © © © © ©. © © © © © © © © © © © © © 8 Rock Exposures © © © . © © © © © ......... © © © © © © © © 9 GENERAL GEOLOGY © . © © © © © © © a © * © © © - © - © ® © © © © © © © 11 Precambrian Rocks © © © © © © © © © © © © © © © © © . © © © © 16 Biotite Gneiss and Associated Rocks © © © © © © © © © © © 16 Rock Descriptions © © © ©.©.„©©© © © © © © © .© © 19 Biotite Gneiss ©©©.©. © © © © © © © © © . © © © 19 Amphibolites © © © © © © © © ©©©©©.©.© © © 28 Amphibolitic Dike Rocks © © © © © © © © © © © © , 40 Granodiorite, Granodioritic Gneiss, and Mixed Granodiorite^Amphibolite and Granodiorite-Hornblende Gneiss . © © © © © © 41 Pegmatites and Aplites © © © © . © © © „ © © © © 45 Structure © © © . © © © © © © © © © . © © © © © © © © 47 Foliation © © © © © © © ©. © © © © © © © © © © © © 47 Lineation © © © © © © © © © © © © © © © © © © © © 48 F 01 dS o e o oooooe oeoooo o_oeoeoo 59 • Origin and Age © © © © • © © © © . © © © © © © © 60 v vi TABLE OF CONTENTS (Continued) Page GENERAL GEOLOGY (continued) Precambrian Rocks (continued) Boulder Creek Granodiorite . o . „ „ „ „ . „ . 62 Rock Descriptions 0 0 0 « . .00 0.000 ... 64 Hornblende Biotite Granodiorite-Biotite Quartz Monzonite „ 0 . o . 64 Leucocratic Quartz Monzonite 0 o <> . o . 0 . 68 Hybrid Rocks . * * . p.* . ... , . * . 70 5Ceno 1 dltb.s. o o . 0 0 0 0 . o o o o . » . 76 Structure .,.•. .....•. © o @ . 0.00 ® . © . » . o 80 Mode of Emplacement and Age . © . © . © © © o . 82 Granophyre Dikes «, © © © © © © ' © © © . © © © © © © © © . © © 83 Rock Description ©. © © © © © © © „© © © © ©©.©■©.© © 85 Structur e © © © © © © © © © © © © © © © © © © © © © © 87 . Ag e © © 0-0 © © © 0.0 o o © © ©.o-o © © 0,0 .© © © o © 87 Quartz V e m s © © © © © © © © © © © © © © © © © © © © © © 88 Permian and Triassic Rocks ,© © © © © . © © © . © © © © © © © © © 89 State Bridge Formation © © © © ©. © © © © .© © . © © © © © © 90 Definition © © © © © © © * © © © © © © © © © © © © © 90 Distribution © © © © © © © © © © © © © © © © © © © © 92 Thickness © © © © ©.©.© © © © © © © © © © ® © © © © © 92 . Lithology © © © o- © o © 0 0 © © © © © © © © 0*0 © © © 94 Correlation © © © © © © © © © © ©. © © © © ,© © © © © © 95 Chinle and Chugwater(?) Formations Undivided © © © © © © 97 Definition © © © © © © © © © © © © © © © © © © © © © 97 Distribution , © © © © © © © © © . © © © © © © © .© © 98 Thickness © © © © © © © © © © © ©. © © © © © © © © © © 99 Lithology ©o © © o,© © © © ©o-o©.© © ©o © © © o© 102 Gorrelation .© © © © © © © © © © © © © © © « © © ©.© © 103 Jurassic Rocks © © © © © © © © © © © © © ©. © © © © © © © © © 104 Sundance Formation „ © © © © ©. © ©: © © © © © © © © © © . © 104 Definition © © © © © © » © © © © © © © © © © © © © © • 104 Distribution © © © © © © © © © © © © © ©, © © © © © © 106 Thickness e © © © © © © © © © © © . © © © © © © © © © 106 Lithology © © © © © © © © © ©.oo o © © © © © o© © © 108 Correlation © © © © © © © © © © © © @ © © © © © © © © 115 Morrison Formation © © © .© © © © © © © © © © © , © © © © © -116 Definition © © * © © © © © © © © © © © © © © © © © © 116 Distribution © © © © © © © © © © © © © © © © © © ©,© 116 Thickness © © © © © © © © © © © © © © © © ■© © © © © © 117 L 1th o1ogy © © © © © © © 0.0 © © ©,© © © © ,© © © © © © 118 Correlation © © © © © © © © © © © © © © ©.© © © © © © 128 Vll TABLE OF CONTENTS (continued) Page GENERAL GEOLOGY (continued) Cretaceous Rocks 128 Dakota Sandstone 128 Definition 128 Distribution 129 Thickness . 129 Lithology . 131 Correlation 142 Benton Shale• „. 143 Definition 143 Distribution 143 Thickness „ „ 143 Lithology „ „. 145 Correlation „ 154 Niobrara Formation 156 Definition . 156 Distribution 156 Thickness „ . 157 Lithology . 162 Correlation . 3JS Pierre Shale . „ 177 Definition „ 177 Distribution 178 Thickness . 178 Lithology . „ 179 Correlation <, 180 Quaternary Deposits „ , 181 Terrace Deposits 181 Landslide Deposits 186 Alluvium „ „ « o . 191 Structure , . » . » . ■ B. ° . 192 Regional Setting . .. .. .. 192 P* aul t S 0*0 O O O O O O O O 0-0 197 Northeast Faults . „ „ „. „ 197 Northwest Faults o , « .. » 201 -Folds o e o o o o o-o o.o o o o 208 kJ O m t S o o o o oo oo o o oo 209 Joints of Precambrian Rocks 214 Joints of Dakota Sandstone 215 viii TABLE OF CONTENTS (continued) Page GEOLOGIC HISTORY 0 e, ©• © © @ © ©.© © © ©,© ©„© © © © © © © © © © 216 ECONOMIC GEOLOGY © © © © © © © © © © © © ©.© © © © © © ©« © © © 222 G old o o © © o o e O O © O O O O 0 0 0 0 0.0 o o o o o o o o - 222 , m* an i. uni © © © © © © © © © ©.© © © © © © © © ©. © © © © © © © © 224 Pegmatites © © © © © © © © © © „ © © © © © © © © . © © ©