Geologists disprove theory about what stopped the formation of the Midcontinent Rift
December 8, 2017
Geologists have corrected a mix-up that made an ancient geological structure in the central U.S. seem hundreds of miles shorter than it really is. The biggest failed rift known to geologists is even bigger than originally thought, according to research that will be presented at the American Geophysical Union fall meeting Dec. 11 in New Orleans.
The Midcontinent Rift, which started but failed to split North America in two pieces 1.1 billion years ago, is the biggest failed rift ever discovered. It was formed when 350,000 cubic miles of volcanic rock poured out of the rift and formed the beautiful cliffs around Lake Superior. South of Lake Superior, the volcanic rocks are covered by younger rocks, so it wasn't clear how far the rift extended.
Read more at:
https://phys.org/news/2017-12-geologists-theory-formation-midcontinent-rift.html#jCp
