The Wetumpka Crater is a shallow marine impact site that dates from the Cretaceous period, about 81 million years ago. It is about 6.5 km in diameter, and is exposed at the surface.
Evidence of Impact Origin
The impact origin of each location listed on this website has been supported by unambiguous diagnostic evidence of hypervelocity impact that has been reported in a scientific (usually peer reviewed) context. Without such evidence, a geological structure is not a confirmed impact crater. This section, which is included for each crater on this website, is not an exhaustive list of such published evidence, but is meant to demonstrate that appropriate work has been done for each listing.
King Jr., D. T., Neathery, T.L., Petruny, L.W., Koeberl, C., Hames, W.E., Shallow-marine impact origin of the Wetumpka structure (Alabama, USA), Earth and Planetary Science Letters 202 p. 541 - 549. 2002
King, Jr., D. T., Neathery, T. L., Petruny, L. W., Koeberl, C. and Hames, W. E., Evidence confirming meteoritic impact at Wetumpka crater, Alabama, USA, Meteoritics and Planetary Science, v 34, n 4, p 63-64. 1999.
Nature of diagnostic evidence:
Other significant evidence: breccia, morphology, elevated Ir, Ni, Cr, Co levels (King et al., 2002)
WETUMPKA’S ANNUAL "CRATER TOURS" -- AN UNUSUAL EDUCATIONAL OUTREACH ACTIVITY IN PLANETARY SCIENCE
Harris et al., 2010. GRAINS OF A FEATHER… LOW-SHOCK PRESSURE DEFORMATION IN SILICATE MINERALS FROM THE WETUMPKA IMPACT STRUCTURE, ALABAMA, USA (Met Soc Abstract 5397)
David T. King, Jr., Lucille W. Petruny, and Thornton L. Neathery. Ecosystem perturbation caused by a small Late Cretaceous marine impact, Gulf Coastal Plain, USA Geological Society of America Special Papers, 2007, 424, p. 97-107.
McHone, J F. and Dietz, R. S. (1992) Earth's multiple impact craters and astroblemes (abstract). Abstracts of the 23rd Lunar and Planetary Science Conference, pp. 887-888.http://www.lpi.usra.edu/meetings/lpsc1992/pdf/1441.pdf
THORNTON L. NEATHERY, ROBERT D. BENTLEY, and GREGORY C. LINES. Cryptoexplosive structure near Wetumpka, Alabama Geological Society of America Bulletin, April, 1976, v. 87, no. 4, p. 567-573.