Isotope dating of rocks new thread
Scientists call formations where one rock is inserted into another "intrusions." The rocks within the formation are "reversed from what we would ordinarily expect," said the study's lead author, Christine Siddoway, a professor of geology at Colorado College in Colorado Springs.
Typically, it is igneous rocks, such as granite, that intrude into sedimentary stone.
An ancient, catastrophic flood or earthquake may explain how a bewildering rock formation in Colorado's Rocky Mountains formed, a new study finds.
For more than 120 years, geologists have wondered how giant chunks of Tava sandstone, a sedimentary rock, had become inserted into a section of the igneous rocks that shape the backbone of the Front Range, within the southern Rockies.
It could have been another large earthquake that forced the sedimentary sandstone into the granite in Colorado, she said.
Or, it could have been rapid-moving floodwaters that lodged the Tava sandstone sediment into a fracture in the granite, explaining the intrusion, Siddoway added.
Whether it was an earthquake or a flood that set the formation into motion, the intrusion as we see it today can be explained by "natural fracking," she said.
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” You cannot know how long the swimmer took unless you knew the time on the wristwatch when the race started. A quick flash to a chart during the debate purportedly showing so, and far too much to read in a second, and then on to somethig else.