Wednesday, October 1, 2008

Upheaval Dome


Day 3 of your trip we were in Canyonland National Park. We went to Upheaval Dome. What is Upheaval Dome? Salt dome or is it a meteorite crater? One hypothesis geologists have says that it is a salt dome that was created when the salts from the Paradox Formation moved upward. The other hypothesis is a meteorite hit 60 million years ago and when it his it made a depression and then rebound flow made the dome in the middle. Erosion has long since eroded the upper part of the impact crater and its debris.  Geologists decided to try and prove which hypothesis was correct. They mapped the rocks of the entire area very carefully. While they were mapping they were looking for faults normal or thrust. If there were normal faults it would be a salt dome, but if they found thrust faults then it would be meteorite caused. They geologist found as they mapped the area that it was all thrust faults. That means that it was meteorite created. Then new proof was found. They found the presence of shocked quartz (quartz fractured in a special way) which is created by a meteorite. Answer to our question of salt dome or meteorite crater...it is a meteorite creator. Check out this site, http://en.wikipedia.org/wiki/Upheaval_Dome, for some more pictures and and a summary of what we talked about.

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