Geochemistry of alteration and mineralization of the Wind River gold prospect, Skamania County, Washington

Author

Krista I. McGowan, Portland State University

Sponsor

Portland State University. Department of Geology

First Advisor

Michael L. Cummings

Date of Publication

1985

Document Type

Thesis

Degree Name

Master of Science (M.S.) in Geology

Department

Geology

Language

English

Subjects

Metamorphism (Geology) -- Washington (State) -- Wind River Region, Hydrothermal deposits -- Washington (State) -- Wind River Region, Geochemistry -- Washington (State) -- Wind River Region, Geology -- Washington (State) -- Wind River Region

DOI

10.15760/etd.5469

Physical Description

1 online resource (151 p.)

Abstract

The Wind River gold prospect is located in TSN, R7E of Skamania County, Washington, and is an epithermal gold-quartz vein system hosted in volcanic rocks of the Ohanapecosh Formation, a late Eocene to middle Oligocene unit of calcalkaline chemical composition. Andesitic pyroclastic rocks of the Ohanapecosh Formation are the host of mineralization in the study area, and form the lowest of several stratigraphic subunits. These pyroclastic rocks are overlain by two sequences of lava flows which cap the ridges and are folded by an anticlinal warp over the length of Paradise Ridge, plunging gently to the southeast. Toward the west, the number of flows decreases and the proportion of intercalated pyroclastic rocks increases. Numerous dikes cut the pyroclastic rocks at the Wind River prospect. Geochemical data show these dikes to have been feeders for the overlying lava flows. Differing degrees of alteration of the dikes relative to the most intensely altered pyroclastic rocks which they cut indicates a complex history of overlapping hydrothermal and volcanic activity at the prospect.

Rights

In Copyright. URI: http://rightsstatements.org/vocab/InC/1.0/ This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).

Comments

If you are the rightful copyright holder of this dissertation or thesis and wish to have it removed from the Open Access Collection, please submit a request to pdxscholar@pdx.edu and include clear identification of the work, preferably with URL

Persistent Identifier

http://archives.pdx.edu/ds/psu/20367

Recommended Citation

McGowan, Krista I., "Geochemistry of alteration and mineralization of the Wind River gold prospect, Skamania County, Washington" (1985). Dissertations and Theses. Paper 3586.
https://doi.org/10.15760/etd.5469