Define Erosion and give an example of where it takes place.

Erosion is the wearing away of an object or substance through an external force. ... The banks of creeks and rivers erode over time as the water moves past it, carrying away sediment and depositing it elsewhere. An example of where a erosion takes place is the Grand Canyon, which was worn away over the course of tens of millions of years by the Colorado River with the help of winds whipping through the formed canyon; the Rocky Mountains in Colorado have also been the subject of intense geological study, with some...

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2. this rock sample is limestone and shale. with what you know about rock formation, what type of environment did these organisms live in?