Decorah Impact Crater
August 26, 2013 | EarthMagazine.org
Researchers have confirmed a 470-million-year-old impact crater near the town of Decorah, Iowa using multiple types of evidence.
Related: Google Map of Impact Sites
July 21, 2013 | MIT
"But there remains one lingering mystery: If the Earth arose from the collision of asteroids, its composition should resemble that of meteoroids, the small particles that break off from asteroids. But to date, scientists have found that, quite literally, something doesn’t add up: Namely, the Earth’s mantle — the layer between the planet’s crust and core — is missing an amount of lead found in meteorites whose composition has been analyzed following impact with the Earth." Quoted from the MIT press release.
Related: What is the Moho?
Colorado Impact Crater?
March 31, 2013 | Colorado Geological Survey on Facebook
The Colorado Geological Survey shares a aerial photo of a bowl-shaped feature with a distinct rim that is about 110 meters across. Could it be an impact structure?