Scholars' Mine Masters Theses Student Theses and Dissertations 1965 Geology of Cienega Mining District, Northwestern Yuma County, Arizona Elias Zambrano Follow this and additional works at: https://scholarsmine.mst.edu/masters_theses Part of the Geology Commons Department: Recommended Citation Zambrano, Elias, "Geology of Cienega Mining District, Northwestern Yuma County, Arizona" (1965). Masters Theses. 7104. https://scholarsmine.mst.edu/masters_theses/7104 This thesis is brought to you by Scholars' Mine, a service of the Missouri S&T Library and Learning Resources. This work is protected by U. S. Copyright Law. Unauthorized use including reproduction for redistribution requires the permission of the copyright holder. For more information, please contact
[email protected]. GEOLOGY OF CIENEGA MINING DISTRICT, NORTHWESTERN YUM.1\, COUNTY, ARIZONA BY ELIAS ZAMBRANO I J'i~& A THESIS submitted to the faculty of the UNIVERSITY OF MISSOURI AT ROLLA in partial fulfillment of the requirements for the Degree of MASTER OF SCIENCE IN GEOLOGY Rolla, Missouri 1965 ~!'Approved by ~2/~advisor) ~ ~·-~~ ii ABSTRACT In the mapped area three metamorphic units crop out: calc-silicates and marble, gneiss, and a conglomerate- schist section. The first one consists of a series of intercalations of calc-silicate rocks, local marbles, and greenschist. Quartzite appears in the upper part of the section. This section passes transitionally to the gneiss, which is believed to be of sedimentary origin. Features indicative of sedimentary origin include inter calation with marble, relic bedding which can be observed locally, intercalation of greenschist clearly of sedimentary origin, lack of homogeneity in composition with both lateral and vertical variation occurring, roundness of zircon grains, and lack of zoning in the feldspars.