Geology and Ore Deposits of the Cottonwood-American Fork Area, Utah: Professional Paper 201

U.S. Geological Survey Professional Paper 201, "Geology and Ore Deposits of the Cottonwood-American Fork Area, Utah," by F.C. Calkins, B.S. Butler, and V.C. Heikes, provides an in-depth geological analysis of the region encompassing the historically significant Cottonwood and American Fork mining districts. This comprehensive study, originally published in 1948, meticulously documents the stratigraphy, structure, and mineralization of the area, focusing on the genesis and distribution of valuable ore deposits. Within these districts, detailed descriptions are provided for prominent mines such as the Cardiff, Emma, Silver King, and Michigan-Utah, among others. The report also documents extensive tunnel systems, including those driven into the mountainsides to access ore bodies, like those found in the vicinity of the Alta and Park City mining areas, though the latter is only mentioned in relation to the general regional geology and not a focus of the mine descriptions. The geographic features of Big Cottonwood Canyon, American Fork Canyon, and the surrounding peaks and drainages are thoroughly mapped and described, providing crucial context for understanding the spatial relationships between geological structures and ore deposits.

This 152-page report, accompanied by 51 figures and plates present contain geological maps, cross-sections, and mine workings diagrams, visually illustrating the complex geological relationships within the study area. These plates are essential for interpreting subsurface geology and ore deposit distribution. The text rigorously addresses the mineralogy and paragenesis of ores, identifying key economic minerals and associated gangue. Stratigraphic analyses cover formations from Precambrian to Tertiary, establishing a comprehensive geological history. The study also explores the structural controls on ore deposition, emphasizing the role of faulting and folding in localizing mineralization. The report details the mining districts within the area, focusing on the specific geology and ore deposits related to each. Mines such as the Columbus, Flagstaff, and others are mentioned, as well as the various mining tunnels that were crucial to accessing the ore bodies.

This publication, offered by the Natural Resources Map and Bookstore, is a reprint of the original U.S. Geological Survey Professional Paper 201 and its associated plates, not an original publication. The scientific integrity of the original work by Calkins, Butler, and Heikes, with support staff, is preserved in this reprint, ensuring continued access to a fundamental study of the Cottonwood-American Fork area's geology and ore deposits, including the mining districts, mines, and tunnels detailed within.