Mount Rushmore community. Recent pine beetle infestations have threatened the forest. Mount Rushmore is largely composed of granite. The memorial is carved on the northwest margin of the Black Elk Peak granite batholith in the Black Hills of South Dakota, so the geologic formations of the heart of the Black Hills region are also evident at Mount Rushmore. The batholith magma intruded into the pre-existing mica schist rocks during the Proterozoic, 1.6 billion years ago. Coarse grained pegmatite dikes are associated with the granite intrusion of Black Elk Peak and are visibly lighter in color, thus explaining the light-colored streaks on the
Mount Gilead State Park Mount Gilead State Park Mount Gilead State Park is located in Morrow County, Ohio, United States to the east of the village of Mount Gilead. Access to the park is via State Route 95. Work on the park began in the early 1900s, with the creation of a dam across Sam's Creek. Work continued through the proceeding decades, with a larger lake being completed below the first one on July 10, 1930. In 1949, the park was turned over to the Ohio Department of Natural Resources. Mount Gilead State Park covers , 32 of which are the lakes. It offers