blue "no trespassing, u.s. government property" sign posted in grassy dunes near the shoreline in winchester bay, oregon. the coastal setting and warning signage suggest a secured or restricted federal area - 美國聯邦土地 個照片及圖片檔
Paleosol developed on Cretaceous Pierre Shale: the Yellow Mounds of Badlands National Park, South Dakota.
oligocene brule formation of the white river group, badlands national park, south dakota - 美國聯邦土地 個照片及圖片檔
View over glacial tarns down the glacially carved, U-shaped valley of North Fork Cut Bank Creek, Glacier National Park, Montana.
Glacial Horn. Split Mountain and burned trees from the 2005 Red Eagle Fire, Glacier National Park, Montana..
Herringbone cross-stratification in Proterozoic Grinnell Formation, part of the Proterozoic Belt Supergroup, Glacier National Park, Montana .蒙大拿州
Morning fog and burned trees from the 2005 Red Eagle Fire, Glacier National Park, Montana. Red Eagle and Little Chief Mountains in background..
