Paleontology and geologyIce sheets advanced over Rhode Island several times during the Quaternary. Evidence of Pleistocene glaciation, such as eskers, drumlins, moraines that cover much of the state, and glacial striations (scratch marks) on bedrock, are easy to find. Block Island, approximately 20 km off the southern coast of Rhode Island, formed about 12,000 years ago as part of a ridge of till (a moraine) when the last ice sheet melted back. |