Date of Award


Degree Name

Master of Science


Geological and Environmental Sciences

First Advisor

Dr. John D. Grace

Second Advisor

Dr. William Harrison

Third Advisor

Dr. W. Thomas Straw

Access Setting

Masters Thesis-Open Access


The Millikan Mine's ore body contains ubiquitous amounts of petroliferous materials occurring as blebs, coal-like pods and veinlets, and seeps coating mine stope walls. Emplacement of hydrocarbons into the ore occurred before the final episode of mineralization ceased, based on growth of dendritic galena in some coal-like bitumen and other paragenetic relationships. Growth of dendritic galena in a hydrocarbon substance suggests that hydrocarbons provided sulfur for galena mineralization by either abiogenetic reduction of sulfate or thermochemical evolution of organic sulfur. Texturally, it also suggests that the presence of hydrocarbons may have been responsible for some zones of rapid precipitate mineralization. One possible source for the petroliferous materials could be the ore-hosting rocks, based on the host rock's enrichment of organic carbon and its association with bituminous seeps. Hydrocarbons may also have been a source for nickel, cobalt, and cadmium.

Included in

Geology Commons