The real beginning of Chepiwanoxet Island came as a result of the last great ice sheets, which bulldozed rock and stone from Canada to Rhode Island. Along the way, each glacier gouged up billions of cubic meters of underlying bedrock, and then ground local and imported rocks together, creating much of the glacial deposits existing today. When the Earth's temperature rose about 10,000 to 12,000 years ago, the glaciers began melting faster than they were moving forward leaving huge deposits of sand and feeding many rivers and streams that rose sea level and washed sand into the coves and bays. For extended periods, the ice advance equaled the rate of melt, and piles of sediment were deposited in terminal or end moraines, such as on Block Island and in Charlestown (hills in the southern part of the state).