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Structural Geology Amd Tectonic History of the Geesaman Wash

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Structural Geology Amd Tectonic History of the Geesaman Wash Structural geology and tectonic history of the Geesaman Wash area, Santa Catalina Mountains, Arizona Item Type text; Thesis-Reproduction (electronic); maps Authors Janecke, Susanne Ursula, 1959- 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 04/10/2021 07:07:35 Link to Item http://hdl.handle.net/10150/558061 STRUCTURAL GEOLOGY AMD TECTONIC HISTORY OF THE GEESAMAN WASH AREA, SANTA CATALINA MOUNTAINS, ARIZONA by Susanne Ursula Janecke A Thesis Submitted to the Faculty of the DEPARTMENT OF GEOSCIENCES In Partial Fulfillment of the Requirements For the Degree of MASTERS OF SCIENCE In the Graduate College THE UNIVERSITY OF ARIZONA 19 8 6 Call No. BINDING INSTRUCTIONS INTERLIBRARY INSTRUCTIONS 1 9 7 9 1 Dept. 1986 Author: Juiecke, S. 69 Title: RUSH_________________ PERMABIND------------------- PAMPHLET--------------------- GIFT------------------------------ M.S. COLOR: POCKET FOR MAP---------- COVERS TUBE Front______ Both Special Instructions - Bindery or Repair REFERENCE------------------- Other------------- ------------- 1 / 9 / 8 7 L-279 V V Call No. BINDING INSTRUCTIONS INTERLIBRARY INSTRUCTIONS Eg 791 Dept. 1986 Author: Janecke, S e 69 Title: RUSH PERMABIND pamphlet M.S. GIFT COLOR: POCKET FOR MAP COVERS TUBE Front Both Special Instructions - Bindery or Repair REFERENCE Other------------------------------------ 1/9/87 L-279 STATEMENT BY AUTHOR This thesis has been submitted in partial fulfillment of requirements 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 acknowledgement 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 or her judgement the proposed use of the material is in the interests of scholarship. In all other instances, however, permission must be obtained from the author. s i g n e d : CJ/\SL^ APPROVAL BY THESIS DIRECTORS This thersis has been approved on the date shown below: G/'H. Davis Date Professor GeologyC\ Vice Provost Professor of Geology ACKNOWLEDGEMENTS It is impossible to acknowledge and thank all those who have helped me in this work. Interaction with many people has greatly improved the final product and has helped to make the project an enjoyable one. I would like to extend special thanks to Ann Bykerk-Kauffman for suggesting the thesis area, stimulating discussion, and encouragement. I thank my thesis committee for allowing me considerable freedom in defining the scope of this work, and for their help and criticism. Editorial comments on the manuscript from George Davis and Peter Coney were particularly helpful, as were discussions with William R. Dickinson. I am very grateful to all those who made the trek to my field area. Barbara Beatty, Ann Bykerk-Kauffman, Peter Coney, George Davis, Bill and Jackie Dickinson, Jim Evans, Steve May, Steve Reynolds, David Richards and Jon Spencer all generously gave their time to visit the study area. Barbara Beatty was an able, hard working and enjoyable field assistant on several occasions. I would like to thank Mr. Neil Labarge for his help in arranging my stay at the Salvation Army Camp O' Wood during my fieldwork. Mr. Gruwell of the U Circle Ranch and the Oracle Ridge Mining Partners granted me free access to the private property in the study area. iii iv Discussions with Steve Reynolds, Gene Suemnicht, Stan Keith and Clem Chase resulted in numerous insights and their help is gratefully acknowledged. Friends and colleagues Steve Naruk, Steve May, Steve Wust, Gary Calderone, Barb Beatty, David Richards, Ken Yeats, Bill Holt, Peter Swift, Margaret Klute, and Bob Krantz provided ideas, constructive criticism, helpful suggestions, and encouragement. I would like to thank Steve May for collecting and analysing numerous paleomagnetic samples from the study area. I am indebted to Steve for drilling and demagnetizing the samples and for stimulating discussion of ideas. Gary Calderone clarified the results of the paleomagnetric work for me and his time is appreciated. Muhammed Shafiqullah provided a K-Ar date from the latite porphyry. Dave Wiltschko kindly made his structure graphics program available to me at Texas A & M University. Access to facilities at Texas A & M University and discussions with students during the summer of 1985 are greatly appreciated. Support for this research was provided by the Laboratory of Geosciences at the University of Arizona, Sigma Xi, Scientific Research Society, and the National Science Foundation through a graduate fellowship awarded to the author. Special thanks go to my parents Joachim and Christa Janecke for their love and support, and for encouragment throughout my academic career. Above all, I would like to thank Jim Evans for his encouragement, scientific insights, editorial comments, patience and love throughout this time. His help and advice have been invaluable. TABLE OF CONTENTS Page LIST OF ILLUSTRATIONS............ ix ABSTRACT .................. xiii 1. INTRODUCTION .............. ................................ 1 2. LITHOLOGY AND STRATIGRAPHY ................................. 8 General Statement ....................................... 8 Precambrian Basement . .......... .................... 9 Metasedimentary Rocks ............ 10 Proterozoic Rocks . ............................. .. 10 Paleozoic Rocks ..................................... 11 Bolsa Quartzite................................. 11 Abrigo Formation ............................... 11 Martin Formation ............................... 12 Escabrosa Limestone ............................. 12 Naco G r o u p ..................................... 13 Mesozoic Rocks ..................................... 14 Bisbee Group ................................... 14 American Flag Formation .............. 15 Cenozoic Rocks ............... 22 Quiburis Formation ............................ 22 Quaternary Alluvium ................ 22 Igneous Rocks ........ 23 Leatherwood Suite . ................................. 23 Rice Peak Granodiorite Porphyry .......... 23 Leatherwood Quartz Diorite. ............. 24 Schistose Porphyrytic Quartz Diorite ........ 25 Cretaceous (?) Mafic Intrusions . .......... 27 Felsite D i k e s ...................................... 28 Tertiary Lamprophyre Dikes and Sills .............. 28 Tertiary Volcanic Rocks ............................. 30 Metamorphism ...................... 32 Contact M e t a m o r p h i s m .......... 32 Regional Metamorphism.............. 34 Discussion ...... ............................. 35 vi vii TABLE OF CONTENTS— Continued Page 3. STRUCTURAL G E O L O G Y ................ ........................ 37 Overview.............. .................................. 37 Form and Orientation of Map U n i t s ...................... 38 B e d d i n g ............................................. 39 Plutonic R o c k s .......... ........................ .. 42 Rice Peak Granodiorite Porphyry . ...... 42 Leatherwood Quartz Diorite . ................ 42 Schistose Porphyritic Sills .............. 45 Volcanic Rocks ..................................... 46 Latite Porphyry ................................. 46 D i s c u s s i o n .............. .......................... 49 Geesaman Fault System ................................... 50 Geesaman F a u l t ............ ........................ 50 Separation Across the Geesaman Fault .......... 50 Units Cut by the Geesaman F a u l t ........ .. 52 Geometry of the Geesaman Fault ......... 54 D i s c u s s i o n ..................................... 57 Stratigraphic Differences Across the Geesaman Fault ............................. 62 Character of the Fault Z o n e .................... 64 Geesaman Fault as Deformational Boundary .... 65 Pidgeon Tank-Bat Hill Fault ........................ 66 Deformational Fabrics .... ........................ 68 Characteristics of Elements ........................ 68 Basement ....................................... 68 Apache Group ................................... 74 Paleozoic Metasedimentary Rocks ................ 76 Mesozoic Metasedimentary Rocks ................ 80 Rice Peak Granodiorite Porphyry................ 82 Leatherwood Quartz Diorite ................ 83 D i s c u s s i o n ..................................... 83 Orientation of Fabrics ..... .................. 85 Foliation................................ 85 Lineation....................................... 90 Discussion of Fabrics ............................... 94 S t r u c t u r e s ............................................. 94 F a u l t s ............................................. 94 F o l d s ............................................... 98 Dikes Swarms ....................... 101 Tension Gashes ..................................... 102 Crenulation Cleavage and Pencil Structure .......... 105 viii TABLE OF CONTENTS— Continued Page 4. KINEMATIC INDICATORS ....................................... 107 Microstructures........................................ 107 Metasedimentary Rocks ............................... 107 Metaplutonic
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