GEOLOGICAL AND GEOCHEMICAL EXPLORATION CHARACTERISTICS OF MEXICAN TIN DEPOSITS IN RHYOLITIC ROCKS Item Type text; Dissertation-Reproduction (electronic) Authors Lee Moreno, José Luis 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 03:39:12 Link to Item http://hdl.handle.net/10150/287857 72-15,604 LEE MORENO, Jose Luis, 1939- GEOLOGICAL AND GEOCHEMICAL EXPLORATION CHARACTERISTICS OF MEXICAN TIN DEPOSITS IN RHYOLITIC ROCKS. The University of Arizona, Ph.D., 1972 Geology | University Microfilms, A XEROX Company, Ann Arbor, Michigan i TfflS DISSERTATION HAS BEEN MICROFILMED EXACTLY AS HECEIVED. GEOLOGICAL AND GEOCHEMICAL EXPLORATION CHARACTERISTICS OF MEXICAN TIN DEPOSITS IN RHYOLITIC ROCKS by Jose Luis Lee Moreno A Dissertation Submitted to the Faculty of the DEPARTMENT OF MINING AND GEOLOGICAL ENGINEERING In Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY WITH A MAJOR IN GEOLOGICAL ENGINEERING In the Graduate College THE UNIVERSITY OF ARIZONA 19 7 2 THE UNIVERSITY OF ARIZONA GRADUATE COLLEGE I hereby recommend that this dissertation prepared under my direction by Jose Luis Lee Moreno entitled Geological and Geochemical Exploration Characteristics of Mexican Tin Deposits in Rhyolitic Rocks be accepted as fulfilling the dissertation requirement of the degree of Doctor of Philosophy f A/w- ^ /^// Dissertation Director Date After inspection of the final copy of the dissertation, the following members of the Final Examination Committee concur in its approval and recommend its acceptance:'" Ccy. // /ro/7/ >— /', m-r Khjij- This approval and acceptance is contingent on the candidate's adequate performance and defense of this dissertation at the final oral examination. The inclusion of this sheet bound into the library copy of the dissertation is evidence of satisfactory performance at the final examination. PLEASE NOTE: Some pages have indistinct print. Filmed as received. University Microfilms, A Xerox Education Company STATEMENT BY AUTHOR This dissertation 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 bor­ rowers under rules of the Library. Brief quotations from this dissertation are allowable without special permission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or re­ production 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 in­ terests of scholarship. In all other instances, however, permission must be obtained from the author. ACKNOWLEDGMENTS The author wishes to thank Drs. W. C. Lacy and W. C. Peters of the Department of Mining and Geological Engineering, The University of Arizona, for their valuable advice and critical review of this paper. Reading of the manuscript by Drs. J. F. Abel, J. M. Guilbert, and J. S. Sumner also proved to be of great value. The field and laboratory work were done as a part of a project sponsored by the Mexican Government through the Consejo de Recursos Naturales No Renovables. The author especially wishes to thank Ing. Guillermo P. Salas, Director General of this organization, for his sug­ gestions and interest in the development of this study. Thanks are also accorded to Ing. Ruben Pesquera V., Exploration Manager of the Consejo de Recursos Naturales No Renovables. Most of the trace element analyses were done by the author at the Department of Geochemistry of the Consejo de Recursos Naturales No Renovables in the city of San Luis Potosi, and some were done by the Bureau de Recherches Geologiques et Minieres of France. The Physical Chemical Laboratories of the Consejo de Recursos Naturales No Renovables did all the chemical and some petrographic analyses of the Mexican rocks studied. Mr. John L.Lufkin of the Geology Department, Stanford University, kindly made available the results of the chemical analyses and petrographic descriptions of some rock specimens from the Black Range tin district of New Mexico. iii The encouragement of my wife Alicia and the happy presence of my daughter Lori contributed greatly to the completion of this work. TABLE OF CONTENTS Page LIST OF ILLUSTRATIONS vii LIST OF TABLES viii ABSTRACT ix INTRODUCTION 1 Objectives 1 History of the Area 3 Location . 3 History 4 GEOLOGIC STUDY 8 Regional Geology 8 Local Geology 9 Tuffs and Ignimbrites 10 Breccias 10 Flow-banded Rhyolites 11 Multiple Linear Regression Analyses 12 Juan Aldama District 12 Sierra de Pinos 23 Tin Deposits and Districts Examined 24 America-Sapioris District 24 Avino Area 29 La Barrosa Mine 29 Los Remedios Mine 30 El Naranjo Mine 30 Juan Aldama District 32 Sierra de Pinos 39 Mineralogy and Origin 45 Mineral Species 45 Solution Chemistry 50 The Emplacement of Rhyolitic Rocks 52 Apparent Geologic Controls 54 PRODUCTION TECHNOLOGY 57 GEOCHEMICAL STUDY 60 Orientation Survey 60 Tin in Natural Surface Waters 60 v vi TABLE OF CONTENTS —Continued Page Tin in Vegetation 62 Tin in Stream Sediments 63 Tin in Soils 66 Trace Elements in Mineralized Rocks 71 Trend Surface Analysis at Juan Aldama 74 Geochemical Experiment at Sierra de Pinos 80 Stream Sediment Survey 84 Soil Survey "B" Horizon 84 Soil Survey "C" Horizon 85 Trend Surface Analysis 86 Diamond Drilling at the Mina Nueva Anomaly 95 CONCLUSIONS 98 SELECTED BIBLIOGRAPHY 104 LIST OF ILLUSTRATIONS Figure Page 1. Index Map of States of Zacatecas and Durango Showing Location of Tin Bearing Areas in pocket 2. Geologic Map and Stream Sediment Geochemical Survey of Sierra de Pinos, Zac., Mexico in pocket 3. Location Map of Mesa del Venado in the Juan Aldama Tin District 34 4. Geologic Map and Location of Tin Mining Works of Mesa del Venado in Juan Aldama, Zac 75 5. Hand-contoured Map of Observed Tin Values in Soils of Mesa del Venado 79 6. First Order Contour Maps of Mesa del Venado 81 7. Second Order Contour Maps of Mesa del Venado 82 8. Third Order Contour Maps of Mesa del Venado 83 9. Geochemical Soil Survey "B" Horizon Area Picacho-Adjuntas in pocket 10. Geochemical Orientation Survey on the Area of Mina San Jose 87 11. Geochemical Orientation Survey in the Area of Mina Nueva 88 12. Geologic Map and Location of Tin Mining Works of Sierra de Pinos 90 13. Hand-contoured Map of Observed Tin Values in Soils of Sierra de Pinos 91 14. First Order Contour Maps of Sierra de Pinos 92 15. Second Order Contour Maps of Sierra de Pinos 93 16. Third Order Contour Maps of Sierra de Pinos 94 vii LIST OF TABLES Table Page 1. Tin Production in Mexico, 1800-1969 5 2. Chemical Analyses of Rhyolitic Rocks from Various Mexican Tin Districts 13 3 . Chemical Analyses of Rhyolitic Rocks from the Black Range Tin Area in New Mexico 14 4. Chemical Analyses of Tin-barren Mexican Rhyolitic Rocks 15 5. Description of Rock Samples Included in Table 2 .... 16 6. Descriptions of Rock Samples Included in Table A .... 20 7. Average Chemical Composition of Some Tin- bearing and Barren Mexican Rhyolitic Rocks 25 8. Trace Element Analyses of Various Cassiterite Samples from the Sapioris District 47 9. Distribution of Tin in Different Size Fractions of Soils, Stream Sediments, and Banks from Durango and Zacatecas 64 10. Distribution of Tin Values Downstream from La Barrosa Mine 66 11. Mineralogical Composition of Alluvial Soil Samples from Various Tin Districts 70 12 . Trace Element Content of Mineralized Rocks of Mesa del Venado, Juan Aldama, Zacatecas 72 viii ABSTRACT The study program was undertaken in central Mexico with the following three main objectives: 1. To investigate the occurrence of tin in rhyolitic rocks in Mexico to make some contribution toward an understanding of the origin and economic significance of this type of deposit, 2. To define certain diagnostic criteria to guide future exploration work in this environment, and 3. To determine and compare the relation between the presence of tin and of other elements and between the presence of tin and the chemical composition of the host rock. The work included geologic observations of many tin prospects of the States of Durango and Zacatecas and geochemical investigation of the response obtained from various materials derived from them. Tin occurs in the rhyolitic environment in three main types of deposits: 1. In vein deposits in tuffs and rhyolites which are commonly nar­ row but which occasionally contain small ore shoots yielding a few hundred kilograms of tin ore with grades from 20 to 30 per­ cent. These deposits are usually mined in a primitive fashion by local miners, called "gambusinos ." Exploitation of this type of ore body would not be economic under any other mining system. ix X 2. Epigenetic disseminations in tuffaceous lenses. These deposits usually have large tonnages and low grades. Here the cas- siterite is found filling lithophysae and any other empty space available. Due to lack of either tonnage or grade in the known deposits of this type, there is not a single one being mined in Mexico. However, it is thought that some deposits might exist with the required tonnage and minimum grade to permit exploita­ tion by open pit methods. 3. Void fillings in brecciated tuffs and rhyolites. These deposits are similar to those in tuffs, except that their morphological constitution is different. All deposits examined during this study are of small extent, suggesting that mineralizing solutions were not abundant in these local- itie s.