Mount Katahdin - Natural History

Natural History

Katahdin is part of a laccolith (an intrusion of magma underground) that formed in the Acadian orogeny, when an island arc collided with eastern North America approximately 400 million years ago. On the sides of Katahdin are four glacial cirques carved into the granite by alpine glaciers and in these cirques behind moraines and eskers are several picturesque ponds.

In Baxter State Park many outcrops of sedimentary rocks have striations, whereas Katahdin granite and Traveler rhyolite lava have weathered surfaces on which striations are commonly not preserved. Bedrock surfaces of igneous rocks which have been buried by glacial sediments and only recently exposed have well preserved striations, as in the vicinity of Ripogenus Dam. Several outcrops of sedimentary rocks along the Patten Road show striations, especially on the north side of the road at Hurricane Deck. A few outcrops near the Pattern Road just north of Horse Mountain are striated as are several outcrops of sedimentary rocks along the road from Trout Brook Farm northward to Second Lake Matagamon.

Fauna include black bear, deer and moose as well as black flies and mosquitos in the spring. Among the birds are Bicknell's Thrush and various songbirds and raptors. The mountain has its own indigenous butterfly related to an Arctic type. The flora include pine, spruce, fir, hemlock, beech, maple, birch, aspen, and diapensia.