Pleasant Mountain, along with the nearby Burnt Meadow Mountains in Brownfield, are unique geological features in Western Maine. Most of the mountains and hills of Western Maine are associated with the coming together of North America, Europe, and Africa to form the supercontinent Pangea. They consist mainly of regional metamorphic schists and gneisses, as well as white granite pegmatite (granite with very large mineral grains) from magma squeezed up into the surrounding metamorphic rock from this compression 400 to 200 million years ago. The Ossipee Mountains, a nearly perfectly circular mountain range 24 miles away in New Hampshire is a ring dike – the uplifted and exposed rocks of a collapsed volcanic caldera. The smaller, oval-shaped Red Hill in Moultonborough, New Hampshire (West of the Ossipee Mountains), Green Mountain in Effingham, New Hampshire, Burnt Meadow Mountains, and Pleasant Mountain (East and Northeast of the Ossipee Range), are all essentially “mini” ring dikes associated with the breakup of the supercontinent Pangea. They all contain rhyolite – chemically the same as granite – except that its individual minerals cannot be seen, as rhyolite is the result of lava that made it to the surface, where granite is the result of magma that remains underground, cools over a long period of time, and through uplift and erosion of surrounding rock, eventually becomes exposed at Earth’s surface.
The North side of Pleasant Mountain is home to Shawnee Peak Ski Area, which connects to the hiking trail system via the North Ridge Trail and Sue’s Way off of the Bald Peak Trail. There are four basic trails traversing the mountain that form an X, with the junction of the X at the summit. These trails are The Southwest Ridge Trail (Southwest side), the Ledges Trail (Southeast side), the Bald Peak Trail, North Ridge Trail, and Sue’s Way (Northeast side), and the Fire Warden’s Trail (Northwest side).
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