Nevada Falls marks where the Merced River plummets almost 600 through a joint in the Little Yosemite Valley, shooting out from a sheer granite cliff and then down to a boulder pile far below.
Nevada Falls, with Liberty Cap (center) and Half Dome (left). Nevada Falls marks where the Merced River plummets almost 600 through a joint in the Little Yosemite Valley, shooting out from a sheer granite cliff and then down to a boulder pile far below.
Devil's Postpile, a spectacular example of columnar basalt. Once molten and under great pressure underground, the lava that makes up Devil's Postpile cooled evenly and slowly, contracting and fracturing into polygonal-sided columns. The age of the formation is estimated between 100 and 700 thousand years old. Sometime after the basalt columns formed, a glacier passed over the formation, cutting and polishing the tops of the columns. The columns have from three to seven sides, varying because of differences in how quickly portions of the lava cooled.
Brain rocks. Sandstone is curiously eroded through the forces water and wind acting over eons. Cracks and joints arise when water freezes and expands repeatedly, braking apart the soft sandstone.
Geometric joints and cracks form in eroding sandstone.
Sandstone joints. These cracks and joints are formed in the sandstone by water that seeps into spaces and is then frozen at night, expanding and cracking the sandstone into geometric forms.
Joints and bolders in the rock formations of Joshua Tree National Park.
Vernal Falls and the Merced River, at peak flow in late spring. Hikers ascending the Mist Trail visible at right. Vernal Falls drops 317 through a joint in the narrow Little Yosemite Valley.
Vernal Falls at peak flow in late spring. Hikers are visible at the precipice of the waterfall. Viewed from the John Muir Trail. Vernal Falls drops 317 through a joint in the narrow Little Yosemite Valley.
Nevada Falls, with Liberty Cap rising above it. Nevada Falls marks where the Merced River plummets almost 600 through a joint in the Little Yosemite Valley, shooting out from a sheer granite cliff and then down to a boulder pile far below.
The brink of Nevada Falls, with hikers visible at the precipice. Nevada Falls marks where the Merced River plummets almost 600 through a joint in the Little Yosemite Valley, shooting out from a sheer granite cliff and then down to a boulder pile far below.