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 Rushmore in popular culture the final battle with the Forever King. Another group shown as having a secret base inside the mountain is the "All Purpose Enforcement Squad" of "Young Justice", in the DC Universe series. The comic book superhero Mister Majestic, a character in the Wildstorm Productions universe, also had a secret base of operations inside Mount Rushmore, analogous to Superman's "Fortress of Solitude". In "", a 1981 animated movie jointly produced by Hanna-Barbera and Tsuburaya Productions, the heroic Ultra Force is headquartered within Mount Rushmore. Mount Rushmore was a primary location of interest in the plot of the 2007 film "" starring