Glasford

Glasford Crater

The Glasford crater, also known by variations such as the Glasford Disturbance or Glasford Structure, is a significant buried impact crater situated in southern Peoria County, Illinois, United States. It stands as one of only two confirmed meteor impact sites within the state, making it a point of interest for geologists and researchers studying Earth's impact history.

Discovery and Characteristics

Discovered in 1963 by the Central Illinois Light Company (CILCO) during drilling operations for underground natural gas storage, the Glasford crater's presence was not immediately apparent from the surface. It is presently concealed beneath agricultural farmland, with its precise location near the intersection of Cowser and Kingston Mines roads. The crater measures approximately 4 kilometers (2.5 miles) in diameter. Its age is estimated to be less than 430 million years, placing its formation in the Silurian period or later, though the impact itself occurred in a marine environment during the Late Ordovician period.

Geological Significance and Potential Climate Impact

Geological investigations have revealed evidence such as shatter cones, indicative of a high-energy impact event. The energy released by the bolide is estimated to have been immense, possibly equivalent to thousands of nuclear bombs or multiple times the force of the Mount St. Helens eruption. Researchers, including geologist Charles Monson, have proposed a potential link between the Glasford crater and the Great Ordovician Meteor Shower. Further studies by Dr. Birger Schmitz suggest that dust dispersed from this impact event may have significantly affected Earth's climate, potentially contributing to the mid-Ordovician Ice Age. The meteorite itself is thought to have originated from the asteroid belt between Mars and Jupiter.