Data Series 895
The Paleocene Fort Union Formation hosts a compositionally diverse array of Eocene plugs, dikes, and sills arrayed around the Eocene Big Timber stock in the Crazy Mountains of south-central Montana. The geochemistry and petrography of the sills have not previously been characterized or interpreted. The purpose of this report is (1) to present available geochemical and petrographic data for several dozen samples of these rocks and (2) to provide a basic interpretive synthesis of these data.
First posted February 4, 2015
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du Bray, E.A., Wilson, A.B., and Van Gosen, B.S., 2015, Geochemical and petrographic data for intrusions peripheral to the Big Timber stock, Crazy Mountains, Montana: U.S. Geological Survey Data Series 895, 19 p., https://dx.doi.org/10.3133/ds895.
ISSN 2327-638X (online)
Appendix 1. Status and Treatment of Samples of Sills and Plugs Peripheral to the Big Timber Stock, Crazy Mountains, Montana
Appendix 2. Geochemical and Petrographic Data for Samples of Sills and Plugs Peripheral to the Big Timber Stock, Crazy Mountains, Montana