Wetumpka

Wetumpka Impact Crater

The Wetumpka impact crater is a significant geological site located in Elmore County, Alabama, United States. It holds the distinction of being the only confirmed impact crater within the state. Situated east of downtown Wetumpka, this structure offers a glimpse into a dramatic ancient event.

Geological Context and Discovery

Estimated to be around 85 million years old, the Wetumpka impact crater dates back to the Late Cretaceous period. This age is determined by fossils found within the youngest disturbed deposits, specifically those belonging to the Mooreville Chalk Formation. The crater spans approximately 4.7 miles (7.6 km) in diameter. Its existence was first noted in 1969–70 by Thornton L. Neathery during regional geological mapping, with the initial scientific publication on the subject appearing in 1976.

Confirmation and Research

While Neathery's discovery laid the groundwork, definitive proof of an impact origin eluded researchers until 1998. In that year, David T. King, Jr. and his colleagues identified shocked quartz in a core sample extracted near the crater's center. This crucial finding provided conclusive evidence. Further research and publications by Auburn University researchers in 2002 solidified the Wetumpka site's status as an internationally recognized impact crater.

Impact Event Details

The celestial body responsible for the Wetumpka crater is estimated to have been a meteorite approximately 1,100 feet in diameter. The impact likely occurred at a shallow angle, between 30 and 45 degrees, from the northeast. At the time of the impact, the region was submerged under a shallow sea, with depths ranging from 300 to 400 feet. Although the crater is considered well-preserved, with remnants of the original impact rim and breccia present, exposures are infrequent due to plant and soil cover, with most accessible areas located on private land.