NEW BEDROCK AND SURFICIAL GEOLOGIC MAPS OF BAXTER STATE PARK AND KATAHDIN, MAINE

Baxter State Park, a forested wilderness area of 209,501 acres, is Maine's largest state park and home to 5,267-foot Katahdin, Maine's highest mountain and terminus of the Appalachian Trail. Most of the bedrock in the Park is of Early Devonian age and records a rich history of marine sedimentation followed by world-class, voluminous, rhyolitic, pyroclastic flows (~407 Ma) that are the carapace of the intruding Katahdin pluton (~407 Ma). Post-Acadian, transitional upward terrestrial to marine sediments that preserve abundant land plant fossils (Emsian or Eifelian), record the erosion of the volcanic edifice but not the breaching of the pluton. Younger pre-Pleistocene history of the Park is not known. However, the Katahdin massif and vicinity include some of the best-developed glacial and periglacial features (late Wisconsinan) in eastern United States, such as cirques, moraines, eskers, very large stoss and lee forms, and patterned ground.

Nearly 70,000 people visit the Park annually and requests for geological information are high. A revised edition of the Geology of Baxter State Park and Katahdin, in preparation by the Maine Geological Survey and dedicated to life-long Baxter enthusiast, Dee Caldwell, includes new bedrock and surficial geology maps; both are on a shaded relief base and at a scale of 1:100,000. A cross section accompanies the bedrock map. While the geology of the area is significant enough to entice the closer inspection that these maps provide, one of the greatest benefits of the maps and accompanying publication is educational. With the large number of visitors interested in the natural landscape, the geology of the park presents an unparalleled opportunity to educate the public in geological processes, and the nature and value of geological investigations. Although the maps can stand alone, discussion of the maps is well integrated in the guide and both will help the Park meet a public need.