The geology and ore deposits of a portion of the Harshaw district, Santa Cruz County, Arizona Item Type text; Thesis-Reproduction (electronic); maps Authors Moores, Richard Charles, 1946- 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 02/10/2021 21:50:35 Link to Item http://hdl.handle.net/10150/566282 THE GEOLOGY AND ORE DEPOSITS OF A PORTION OF THE HARSHAW DISTRICT, SANTA CRUZ COUNTY, ARIZONA by Richard Charles Moores, II A Thesis Submitted to the Faculty of the DEPARTMENT OF GEOSCIENCES In Partial Fulfillment of the Requirements For the Degree of MASTER OF SCIENCE WITH A MAJOR IN GEOLOGY In the Graduate College THE UNIVERSITY OF ARIZONA 19 7 2 STATEMENT BY AUTHOR This thesis has been submitted in nartial 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 soecial permission, provided that accurate acknowledgment of source is made. Requests for permission for extended ouotaticn from or reorqduction of tiiis 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 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: 'MGJBrvdr J. MA GUILDER! Date Professor of Geology ACKNOWLEDGEMENTS Although the author must accept principal credit for this manuscript, a number of people have contributed to its completion. The author would like to express his gratitude to them at this time. First, the author would like to thank American Smelting and Refining Company for its generous support and cooperation. Messrs. Courtright and Davis were particularly helpful in aiding the author in his research. This field and laboratory work could not have been suc­ cessful without the assistance given to the author by ASARCO. Special thanks go to my thesis director. Associate Professor John M. Guilbert, for his interesting consultation on and critical review of this paper. The author is also indebted to Professors S. R. Titley and T. S. Lovering for their activities on my thesis committee and to Professor Donald K. Bryant for his aid in fossil identification. Mr. Tom Teska instructed the author in the use of the electron probe. The author is grateful to W. C. Butler for his aid in the determination of the Paleozoic stratigraphy of the map area as well as for his photography. Roger Weller and Mary Chavez are responsible for the preparation of a number of figures in this thesis and Miss M. J. Murphy and Mrs. Susan Edwards typed it in its finished form. Last, but by no means least, I would like to give my sincerest thanks to my wife, Dorothea. Without her help in its preparation, this thesis could not have been comoleted. iii TABLE OF CONTENTS Page LIST OF ILLUSTRATIONS................................................................................. V ABSTRACT.......................... vii INTRODUCTION................................................................................ 1 to ir* co ir* to Location and Access . , Topography and Drainage . Climate and Precipitation Flora and Fauna ....................................................................... 10 GEOLOGY . ................................................................................ 11 Scherrer Formation. ..... ....................... .................. 12 Concha Limestone. .... ....................... ......... 15 Tertiary Extrusive Rocks.......................... 20 Tertiary Fine-Grained Material. ..... ....................... 35 Chief Conglomerate, ........ ................................ 38 Rhyolitic Intrusive Rocks .................................................. 45 Tertiary Diabase. .............................................................. 48 Quartz Latite Porphyry. ..... ....................... ..... 55 Gila-Type Conglomerates ........... .................. 62 Recent Sediments. ................................................................................. 63 Structural Geology. .... .................................... ..... 64 Geologic History.' . ............................... 68 MINERALIZATION. ........... ............................................. 71 Alta M ine...................... 73 American Mine .................. ................ 74 Bender Nine ................. .................. 75 Black Eagle Nine...................... 76 Hermosa Nine...................... .77 Hardshell Nine.......................................................................................... 80 Salvador Mine ..................... 33 Blanket-Like Silver-Manganese Mineralization. ..... 34 SUMMARY AND CONCLUSIONS ............................................................................ 94 LIST OF REFERENCES................................... 96 iv LIST OF ILLUSTRATIONS Page Figure 1. Location M ap...................... .................................................................... 4 2. Geology and Ore Deposits of a Portion of the Harshaw D istrict, Santa Cruz County, Arizona ....................... in pocket 3. Terrain and Vegetation Typical of the Thesis Area .... 6 4. Canelo Hills ................................................................................................... 9 5. Intraclasts in the Scherrer Formation .......................................... 13 6. Permian F o s s i l s ......................................................................................... 16 7. A rchaeocidaris.............................................................................................. 17 8. Concha Limestone-Tertiary Extrusive Rocks Contact .... 18 9. Purple R h y o l i t e .......................................................... 22 10. Photomicrograph of Purple Rhyolite . ........................................ 23 11. Red R h y o lite................................................................................................... 24 12. Photomicrograph of Red Rhyolite ....................... ....................... 25 13. Lithophysae from Hermosa Canyon ...................................................... 27 14. Internal Structure of Lithophysae ........................................ 28 15. Upper Purple Rhyolite ............................................................... 30 16. Spherulites .......................... 31 17. Limestone-Volcanic Rock Mix ............................................................... 32 18. Igneous Dikelet Cutting Limestone .................................................. 33 19. Tertiary Fine Grained Material . ...................................................... 36 20. Photomicrograph of Fine Grained Material .................................... 37 v LIST OF •ILLUSTRATIONS—Continued Page Figure 21. Geologic Cross-Section A-A1 of a Portion of the Harshaw D istrict, Santa Cruz County, Arizona . in pocket 22. Geologic Cross-Section B-B' of a Portion of the Harshaw D istrict, Santa Cruz County, Arizona . in pocket 23. Matrix Intruding Fragment of Chief Breccia ....... 39 24. Intricate Fold in Fragment ............................................. 41 25. S ilicification of Fragment ........................................................... 42 26. Photomicrograph of Rhyolite Dike . .......................................... 46 27. Photomicrograph of Andesite ........................................ 49 .28. A ndesite.................................................................................................. 50 29. Amygdaloidal A n d e s ite ................................................................... 51 30. Photomicrograph of Amygdaloidal Andesite ............................... 53 31. Quartz Latite Porphyry S i l l ...................... 56 32. Quartz Latite Porphyry . ...................................................... 57 33. Photomicrograph of Quartz Latite Porphyry ......................... 58 34. Andesite Xenolith in Quartz Latite Porphyry .................. 59 35. Metal Distribution in Mines around Laramide Intrusive Rocks, Patagonia Mountains, Arizona ................................ 61 36. Manganese Ore.......................................................................................... 72 37. Hermosa M ine.............................................................. 78 38. Hardshell M ine.................................................................................... 81 39. Photograph from Electron P ro b e................................................. 85 40. Manganese Oxide Replacement Ore .............................................. 87 41. Open-Space Manganese O r e ................................... 88 ABSTRACT The map area is in the east side of the Patagonia Mountains near Harshaw, Santa Cruz County, Arizona. Mineral wealth has been sought in the semi-arid Patagonia Mountains since Snanish colonial times, with varying degrees of success. Although Permian sedimentary rocks occur in the southwest corner of the thesis area, Lower Tertiary ignimbrites, flows, tuffs, and flow-breccia are by far the most important rock types