structure, wisconsin

Crater Hunters Find New Clues to Ancient Impact Storm

The Earth will never catch up to the moon (let’s hope), but the number of Ordovician craters may soon takeoff. That’s because it’s easier and cheaper than ever to sniff out the shocked minerals that confirm an impact. My work on my impact site, Brussels Hill in Wisconsin, is featured in this article, which is… Continue reading Crater Hunters Find New Clues to Ancient Impact Storm


Shock metamorphism & shatter cones

Above: A shatter cone in dolomite from the Kentland, Indiana impact structure (Specimen from Lawrence University.) Meteorite impacts are pretty amazing things. An impact crater forms instantaneously on a human time scale, with the shock wave from the impact propagation through the target rock in the following stages: contact and compression, crater excavation, and crater modification. Some… Continue reading Shock metamorphism & shatter cones