quarta-feira, 10 de julho de 2013
Iowa impact crater confirmed
Alexandria, VA -- Scientists have recently confirmed the existence of an impact crater buried below the town of Decorah, Iowa. Scientists first discovered what they thought resembled a crater in 2008, but now it has been corroborated by an airborne geophysical survey and hydrology surveys. Scientists estimate the diameter of the crater at 5.5 kilometers wide, nearly five times the size of the Barringer Meteor Crater in Arizona.
Based on the crater's size, scientists calculate that the region was likely hit by a meteorite roughly 250 meters in diameter about 500 million years ago, and could be related to other Midwestern impact craters. Statistically, similar-sized impactors could hit Earth's surface every 30,000 to 60,000 years.
Read further in the July issue of EARTH Magazine to learn more about the crater and what implications it might have for the availability of water and mineral resources:http://bit.ly/1dbqO43.
Don't miss the other great articles in the July issue of EARTH Magazine. Discover how the "X-Man" alga acquires its mutant abilities; learn more about the discovery of and legal battles over the Kennewick Man; and read one geologist's take on science and faith, all in this month's issue of EARTH, now available on the digital newsstand at http://www.earthmagazine.org/digital.
Source: American Geosciences Institute
Publicado por Jorge M. Gonçalves às 9:42 da tarde