Figure 11. Storm waves move the stones up the beach, leaving ridges, or "berms", at particular elevations. Lower berms are reworked by later storms, so the higher berms represent older storms. Most of the stones on the beach are light gray, greenish-gray, and lavender-gray rocks eroded from the Kittery Formation. Compare the color with the bedrock in the foreground, except that any chemical weathering stains are worn away from the cleaner beach stones by wave action (Photo by Stephen M. Dickson).
Last updated on October 4, 2012