Date of Award

2019-01-01

Degree Name

Doctor of Philosophy

Department

Geological Sciences

Advisor(s)

Philip C. Goodell

Abstract

The Sierra Madre region is rich in mineralized deposits, but it is hard to access because of the rugged terrain. Remote sensing and GIS can help in mineral exploration and regional structural analysis. The purpose of this project is to study linear, curvilinear, arcuate, and circular features in the Sierra Madre Occidental of Mexico in order to improve exploration possibility. It is of great interest to know the relationship between lineament intersections, caldera features because of the location of potential mineral occurrences. In this study, 4,445 lineaments were mapped manually using directional filters applied to satellite images. A total of 26,031 lineaments were extracted automatically with the line module of PCI Geomatica based on automatic detection algorithms (canny algorithms). The remote sensing analysis successfully identified 34 first-order lineaments (FOL) with lengths > 15 km. The FOL help to identify horsts, grabens, and strike-slip faults. The contrast in results between FOL and third-order (TOL) (less than 3 km) is interpreted to represent predominately early versus late tectonic events. The remote sensing analysis identified 17 new previously unknown calderas. Mineral occurrences and mines are generally but not exclusively associated with caldera rims and internal fractures and faults. A positive correlation exists between FOL and mineral occurrences. These results can be useful for future mineral exploration.

In this work, a new method is applied to target alunite. This method can help detect gold mineralization in large areas such as the Sierra Madre Occidental where rugged topography has limited access to certain areas. This technique can help to distinguish alunite (KAl3 (SO4)2(OH)6) from clays, iron oxides (Fe2O3, Fe3O4 or FeO[OH] and jarosite (KFe3[OH]6[SO4]2). This technique can be used to discover epithermal and porphyry deposits during regional exploration efforts. This is important for exploration companies since ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) satellite imagery is a cheap and widely available dataset. Several sites in the area of interest have been identified to be good targets for exploration.

Statistical data analyses are applied into three different deposits in the greater Temoris Mining District: Guerra al Tirano (100 samples), Guadalupe (2,985 samples) and La Millonaria (30 samples).Univariate, bivariate, and multivariate data distributions are analyzed to characterize the elemental geochemistry of the epithermal deposits. The precious metals (Au and Ag) at Guerra al Tirano are correlated with the base metals (Cu, Pb and Zn). However, the precious metals (Au and Ag) at Guadalupe and La Millonaria behave independently of the base metals (Cu, Pb and Zn). They were deposited in different paragenetic periods. The use of Ag/Au values is useful in exploration. The use of base metal ratio is not useful.

Language

en

Provenance

Received from ProQuest

File Size

146 pages

File Format

application/pdf

Rights Holder

Labdan Nijr Alqahtani

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