Abstract

The origin of the Vredefort Structure has been in question since its discovery.  This seems partially due to distortion by post-impact tectonics and partially to the fact that out of fear human nature prefers to believe that structures of such size are of purely terrestrial origins.  Evidence to the contrary is not always apparent to the naked eye given this structure�s  age of about 2000 Ma years, leaving plenty of opportunity for erosion.  This structure�s origin is becoming more apparent as more impact characteristics are discovered such as shock metamorphic microdeformations in quarts and zircon.  It has also recently been shown that the Vredefort melt rocks, shatter cones, and silica polymorphs (coesite and stishovite) show evidence of impact.

Koeberl, Christian and Virgil L. Sharpton.  2001.  Terrestrial Impact Craters.  Lunar and Planetary Institute.  http://www.lpi.usra.edu/pub/publications/slidesets/impacts.html  5/9/01.

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This paper was completed as part of the course requirements for Geo117. All source materials have been acknowledged to the best of our ability. The course was taught by Mr. Bruce Simonson, Professor and Chair, Oberlin College Geology Department, with assistance related to the research process for geological and related information from Ms. Alison Ricker, Science Librarian.