Wetumpka crater
Encyclopedia
The Wetumpka impact crater is the only confirmed impact crater
in Alabama
, United States. It is located east of downtown Wetumpka
in Elmore County
. The crater is 7.6 km in diameter and its age is estimated to be about 83 million years (Cretaceous
) old based on fossils found in the youngest disturbed deposits, which belong to the Mooreville Chalk Formation
. The crater is well preserved, including the original impact rim and breccia, but exposures are few owing to plant and soil cover, and nearly all are on private land.
Thornton L. Neathery discovered the Wetumpka Crater in 1969-70 during regional geological mapping and published the first article on the subject in 1976. However, conclusive evidence of impact origin was lacking until 1998 when David T. King, Jr. and colleagues discovered shocked quartz
in a core drilled near the center of the structure. In 2002, Auburn University researchers published evidence and established the site as an internationally recognized impact crater.
Impact crater
In the broadest sense, the term impact crater can be applied to any depression, natural or manmade, resulting from the high velocity impact of a projectile with a larger body...
in Alabama
Alabama
Alabama is a state located in the southeastern region of the United States. It is bordered by Tennessee to the north, Georgia to the east, Florida and the Gulf of Mexico to the south, and Mississippi to the west. Alabama ranks 30th in total land area and ranks second in the size of its inland...
, United States. It is located east of downtown Wetumpka
Wetumpka, Alabama
Wetumpka is a city in Elmore County, Alabama, United States. At the 2000 census the population was 5,726.The city is the county seat of Elmore County, one of the fastest growing counties in the state....
in Elmore County
Elmore County, Alabama
Elmore County is a county of the State of Alabama. Its name is in honor of General John A. Elmore. As of 2010 its population was 79,303. Its county seat is Wetumpka.This county is part of the Montgomery Metropolitan Statistical Area.- History :...
. The crater is 7.6 km in diameter and its age is estimated to be about 83 million years (Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...
) old based on fossils found in the youngest disturbed deposits, which belong to the Mooreville Chalk Formation
Mooreville Chalk Formation
The Mooreville Chalk Formation is a geological formation in North America, within the U.S. states of Alabama and Mississippi. The strata date back to the early Santonian to the early Campanian stage of the Late Cretaceous. The chalk was formed by pelagic sediments deposited along the eastern edge...
. The crater is well preserved, including the original impact rim and breccia, but exposures are few owing to plant and soil cover, and nearly all are on private land.
Thornton L. Neathery discovered the Wetumpka Crater in 1969-70 during regional geological mapping and published the first article on the subject in 1976. However, conclusive evidence of impact origin was lacking until 1998 when David T. King, Jr. and colleagues discovered shocked quartz
Shocked quartz
Shocked quartz is a form of quartz that has a microscopic structure that is different from normal quartz. Under intense pressure , the crystalline structure of quartz will be deformed along planes inside the crystal...
in a core drilled near the center of the structure. In 2002, Auburn University researchers published evidence and established the site as an internationally recognized impact crater.