Figure 4. Between the Mine Gallery and the Minerals Gallery is a section of the Hall which focuses on geologic processes. Visitors are free to touch and feel the specimens on display here, including this large one of a pothole that was excavated from a coastal setting in Georgetown, Maine. Potholes form over thousands of years by the scouring action of pebbles and cobbles caught in a depression and swirled by water. In this example, a two-foot wide pothole has formed in pegmatite (the rusty colored rock on the right) and schist (the dark layered rock on the left and bottom of the specimen). The fluting on the vertical sides of the specimen are where it was drilled to remove it from the ledge.
Last updated on October 6, 2005