You are not currently logged in.
Access JSTOR through your library or other institution:
If You Use a Screen ReaderThis content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Bushveld Igneous Complex, South Africa: Absence of Shock-Metamorphic Effects in a Preliminary Search
Bevan M. French and Robert B. Hargraves
The Journal of Geology
Vol. 79, No. 5 (Sep., 1971), pp. 616-620
Published by: The University of Chicago Press
Stable URL: http://www.jstor.org/stable/30059992
Page Count: 5
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preview not available
A field and laboratory search for shock-metamorphic features associated with the Bushveld Igneous Complex, South Africa, was made to test the hypothesis that the structure formed by meteorite impact. Samples collected from inliers of basement rock within the complex (the Assen and Marble Hall fragments) and from the Rooiberg series exhibit no megascopic or microscopic shock effects. In particular, shatter cones, Sudbury-type breccias ( = Vredefort pseudotachylite), and planar shock lamellae in quartz are absent. Any shock-metamorphic features originally present have probably been obscured by the emplacement of the widespread Bushveld igneous rocks and by the resulting extensive thermal metamorphism of both the basement rocks and the Rooiberg series. More extensive sampling is needed to test the impact hypothesis adequately.
The Journal of Geology © 1971 The University of Chicago Press