The upper Paleozoic stratigraphy of the Quimby Ranch area, Southern Guadalupe Canyon Quadrangle, Cochise County, Arizona Item Type text; Thesis-Reproduction (electronic); maps Authors Dirks, Thomas Nelson, 1941- 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 27/09/2021 04:58:13 Link to Item http://hdl.handle.net/10150/551843 THE UPPER PALEOZOIC STRATIGRAPHY OF THE QUIMBY RANCH AREA, SOUTHERN GUADALUPE CANYON QUADRANGLE, COCHISE COUNTY, ARIZONA by Thomas N . Dirks 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 6 STATEMENT BY AUTHOR This thesis has been submitted in partial ful­ fillment of requirements for an advanced degree at The University of Arizona end 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 Judgment the proposed use of the material is in the interests of scholarship. 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: OSEPH F. SCHREIBER. JR. ' Date L s Professor of Geology ACKNOWLEDGMENTS The author is most grateful to Dr. Joseph F. Schrelber, Jr., thesis director, for his continual guidance and enthusiasm throughout this project. Acknowledgment of assistance is also due to the other members of the thesis committee* Dr. D. L. Bryant, and Dr. W. D. Pye. Advice on age relationships and the identification of fusulinids by W. J. Stewart and A. J. Wells, both of Texaco, Incorporated, Midland, Texas is particularly appreciated. Shell Oil Company kindly made available stratigraphic sections of southern Arizona and New Mexico. Thanks are extended to Mrs. Mabel Qulmby of Douglas, for the use of her ranch and to Alastalr M. Reid, a fellow graduate student, for the identification of corals and technical assistance. The author is especially indebted to his wife, Karen, for field assistance, typing rough drafts, and constant en­ couragement which brought this project to completion. ill TABLE OP CONTENTS Sags LIST OF ILLUSTRATIONS............................. vi LIST OF TABLES.................................... vlll ABSTRACT........................................... lx INTRODUCTION....................................... 1 Location...................................... 1 Purpose..................................... 3 Method of Study............................... 4 Previous Work................................ 4 UPPER PALEOZOIC STRATIGRAPHY...................... 7 General Statement............................ 7 Earp Formation................................ 8 General statement....................... 8 Measured sections....................... 10 Age and correlation...................... 13 Conditions of deposition.... ............ 18 Collna Limestone.............................. 20 General statement....................... 20 Measured sections....................... 22 Age and correlation...................... 23 Conditions of deposition................. 27 Epitaph Dolomite.............................. 27 General statement....................... 27 Measured section......................... 29 Age and correlation...................... 30 Conditions of deposition................. 33 POST-PALEOZOIC STRATIGRAPHY 35 Lower Cretaceous......... 35 General statement.... Lowell Formation.... U Quaternary......... ...... 38 Older alluvium...... 38 San Bernardino basalt 38 Younger alluvium..... 39 Iv v TABLE OP CONTENTS (continued) Page STRUCTURE 41 General Statement.............................. 41 Qulmby Hills.................................. 41 Faults................................... 41 Folds.................................... 43 Hill 14....................................... 44 Faults............................. 44 Folds. ................................... 45 GEOLOGIC HISTORY............................... 4? APPENDIX........................................... 54 Earp Formation measured section 1 ............ 54 Earp Formation measured section II........... 58 Earp Formation measured section III.......... 63 Collna Limestone measured section I-A.........68 Colina Limestone measured section I-B....... 71 Epitaph Dolomite measured section I ......... ?4 REFERENCES CITED 77 LIST OP ILLUSTRATIONS Figure Page 1. Index map of thesis area.................. 2 2. a. Western end of Hill 14 showing the topo­ graphic expression of the Collna Limestone and the upper and lower members of the Earp Formation b. Upper siltstone member of the Earp Formation showing its resistant and nonreslstant character.................. 12 3« a. Photomicrograph of packed fusulinid biomlerudite; Earp Formation b. Hand specimen' of packed fusulinid biomierudite showing fresh and weathered surface; Earp Formation c. Sawed and polished slab of packed fusulinid biomierudite; Earp Formation d. Photomicrograph of oomicrlte; Collna Limestone e. Hand specimen of oomicrlte showing oolites on weathered surface; Collna Limestone f. Hand specimen of dolomite sedimentary breccia; Epitaph Dolomite............... 50 4. a. Branching bryozoans etched with acetic acid; Collna Limestone b. Productid brachiopods with spines intact; Collna Limestone o. Silty packed gastropod biomierudite; weathered and polished slab; Earp Formation d. Phyllold algae in mlcritic matrix; Earp Formation 4) . Euomphalus pemosus; Earp Formation . Branching bryozoans in mlcritic matrix; Earp Formation.......................... 51 5. a. Lithosparrudlte; polished slab; Earp Formation b. Syrlngopora-llke coral; sllicifled hand specimen; Earp Formation vl vll LIST OF ILLUSTRATIONS (continued) Figure Page 5* c. Syrlngopora-llke coral; polished slab; Earp Formation d. Syrlngopora-llke coral; photomicrograph of cross-section showing Internal septal spines; Earp Formation........... 52 6. a. Llthosparlte; photomicrograph; Earp Formation b. Poorly winnowed blomlcrlte; photo­ micrograph; Earp Formation c. Poorly winnowed blomlcrlte; photo­ micrograph; Earp Formation d. Packed blosparlte; photomicrograph; Earp Formation e. Oolitic dolomite; photomicrograph; Epitaph Dolomite f . Dolomite; photomicrograph; Epitaph Dolomite................................ 53 Plate I Geologic map of the Qulmby Ranch area................................ in pocket II Geologic cross sections of the Qulmby Ranch area................... In pocket III Columnar sections of the upper Paleozoic stratigraphy of the Qulmby Ranch area with faunal identifications............... in pocket LIST OF TABLES Table Page 1. Classification of carbonate rocks........... 5 vill ABSTRACT The Qulmby Ranch area is located in the extreme southeastern corner of Arizona. Upper Paleozoic rocks, assigned to the Naco Group, make up the Qulmby Hills and Hill 14 in this area. The following three formations, in ascending order, crop out in the hillss Earp Formation, Colina Limestone, and Epitaph Dolomite. A stratigraphic study of these formations disclosed that approximately 2800 feet of limestone, dolomite, and siltstone strata are exposed. A petrographic study of these strata and their associated faunas suggest a warm, shallow sea in which sedimentation kept pace with basin subsidence. A trans­ gression in the general regressive phase occurred during Early Leonardlan time with the deposition of the Colina Limestone. Measured stratigraphic sections and the Identification of the abundant fusulinld fauna have estab­ lished a better understanding of the correlation and the age relationships between the upper Paleozoic rocks of Arizona and New Mexico. Other strata that outcrop in the area are the Lowell Formation of the Lower Cretaceous Bisbee Group and the San Bernardino basalt of Quaternary age. Various kinds of alluvium reflect the variety of rock types in the vicinity. lx X The upper Paleozoic rocks in the Quimby Ranch area were thrust faulted prior to the mid-Tertiary high-angle normal faulting that elevated the hills to their present position. INTRODUCTION Location The area of study is located In the southeastern part of the San Bernardino Valley in the extreme south­ eastern corner of Arizona. As shown on the index map (Pig. 1), the area investigated consists of approximately 12 square miles in the northeastern part of T. 24 s., R. 31 E., Cochise County, Arizona. This area, the Qulmby Ranch area, and the enclosed two topographic features. Hill 14 and the Qulmby Hills, have been named by the author. These names shall be used throughout this thesis for the sake of clarity and convenience. Hill 14 is an assemblage of hills predominantly occupying section 14. The Qulmby Hills are named for the hills that lie to the north of Hill 14 and to the southeast of the Qulmby Ranch. The average elevation of the Qulmby Ranch area is 4200 feet, with the highest feature. Hill 14, reaching an elevation of 4738 feet. This area