Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Science 27 May 1977:
Vol. 196. no. 4293, p. 977
DOI: 10.1126/science.196.4293.977
Prev | Table of Contents | Next

Articles

Evidence for Late Tertiary Volcanic Activity in the Northern Black Hills, South Dakota

JAMES G. KIRCHNER 1

1 Department of Geography-Geology, Illinois State University, Normal 61761

Rhyolitic volcanic rock in the northern Black Hills has a potassium-argon isotopic age of 10.5 ± 1.5 million years. This is considerably younger than any previously reported igneous activity in this or adjacent areas and indicates that the renewed uplift of the Black Hills, which occurred after the Oligocene epoch, was also accompanied by some volcanism.

Submitted on November 10, 1976
Revised on January 17, 1977

To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)