Masters Theses

Abstract

"A thick section of presumably Precambrian gneiss with thin intercalated bands of marble and schist has been mapped. There is structural continuity within these rock types as they are mutually intercalated, conformable, have gradational relations and show equal participation in the same individual fold. The layers of schist and marble in the gneiss can be followed over long distances. These rocks have undergone intense regional metamorphism, primarily dynamic, with a possible regional compressive force generated from NW-SE giving rise to sets of folds and faults in the area. From structural, petrographic and field evidence, it is concluded that the metamorphic rocks within the thesis area are of sedimentary origin, brought to their present status by regional metamorphism. From the standpoint of their mineral assemblages and mutual mineral relationships, it is believed that the temperature range of metamorphism was about 400⁰-500⁰C., with a possible water pressure of 3000-8000 bars, corresponding to the albite-epidote-amphibolite facies of Williams, Turner and Gilbert (1954). Metamorphism has been mainly mechanical with a slight influence of temperature. Cataclastic metamorphism has hastened recrystallization, influenced metamorphic differentiation, and produced a great deal of mineralogical and textural changes in the gneiss, schist and marble. Hematite and copper carbonate mineralization is mostly confined along beds of marble, zones of faulting and other structural intersections. Both replacement and filling types are typical of hematite mineralization, which is believed to be both hydrothermal and metamorphic in origin and of two different ages. Little is known about copper ores since sulfides were not found at the surface or in the study of polished sections. The copper carbonates are believed to be the result of groundwater oxidation of sulfides, which are known from previous mining activity to occur at depth"--Abstract, page ii-iii.

Advisor(s)

Brownlow, Arthur H.

Committee Member(s)

Christiansen, Carl R., 1921-1997
Rupert, Gerald B., 1930-2016
Proctor, Paul Dean, 1918-1999

Department(s)

Geosciences and Geological and Petroleum Engineering

Degree Name

M.S. in Geology

Publisher

University of Missouri at Rolla

Publication Date

1965

Pagination

vii, 88 pages, maps

Geographic Coverage

Yuma County (Ariz.)

Rights

© 1965 Henry E. Fernandez, All rights reserved.

Document Type

Thesis - Open Access

File Type

text

Language

English

Subject Headings

Geology -- Arizona -- Yuma CountyGeology -- Maps -- Arizona -- Yuma County

Thesis Number

T 1755

Print OCLC #

5968315

Electronic OCLC #

797020615

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