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 Jefferson State Natural Area Mount Jefferson State Natural Area Mount Jefferson State Natural Area is a North Carolina state park in Ashe County, North Carolina in the United States. Located near Jefferson, North Carolina, it includes the peak of Mount Jefferson, named for Thomas Jefferson and his father Peter, who owned land nearby and surveyed the North Carolina-Virginia border in 1749. In 1939 the Works Progress Administration created a road enabling widespread access to Mount Jefferson, which at the time had no official name and was primarily referenced to as Panther Mountain, likely due to a local legend of a panther once eating a