Moro Rock
Encyclopedia
Moro Rock is a granite dome
rock formation
in Sequoia National Park
, California
, USA. It is located in the center of the park, at the head of Moro Creek, between Giant Forest
and Crescent Meadow. A stairway, built in the 1930s by the Civilian Conservation Corps
, is cut into and poured onto the rock, so that visitors can hike to the top. The view from the rock encompasses much of the Park, including the Great Western Divide
. Use of this trail is discouraged during thunderstorm
s and when it is snowing.
. However, climbing is prohibited during peregrine falcon
nesting season.
. Common in the Sierra Nevada, these domes form by exfoliation
, the spall
ing or casting off in scales, plates, or sheets of rock layers on otherwise unjointed granite. Outward expansion of the granite results in exfoliations. Expansion results from load relief; when the overburden that once capped the granite has eroded away, the source of compression is removed and the granite slowly expands. Fractures that form during exfoliation tend to cut corners. This ultimately results in rounded dome-like forms.
Granite dome
A granite dome is a dome of granite, formed by exfoliation.-Formation:Granite forms plutons of igneous rock several kilometers below the surface as magma slowly cools and crystallizes. The granite is under great overhead pressure....
rock formation
Rock formations in the United States
The following is a partial list of rock formations in the United States, by state:-Arizona:*Canyon de Chelly National Monument**Spider Rock*Chiricahua National Monument**Duck on a Rock**Organ Pipe**Mushroom Rock**Sea Captain*Monument Valley...
in Sequoia National Park
Sequoia National Park
Sequoia National Park is a national park in the southern Sierra Nevada east of Visalia, California, in the United States. It was established on September 25, 1890. The park spans . Encompassing a vertical relief of nearly , the park contains among its natural resources the highest point in the...
, California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
, USA. It is located in the center of the park, at the head of Moro Creek, between Giant Forest
Giant Forest
The Giant Forest, famed for its giant sequoia trees, is within Sequoia National Park. This montane forest, situated at over above mean sea level in the western Sierra Nevada of California, covers an area of...
and Crescent Meadow. A stairway, built in the 1930s by the Civilian Conservation Corps
Civilian Conservation Corps
The Civilian Conservation Corps was a public work relief program that operated from 1933 to 1942 in the United States for unemployed, unmarried men from relief families, ages 18–25. A part of the New Deal of President Franklin D...
, is cut into and poured onto the rock, so that visitors can hike to the top. The view from the rock encompasses much of the Park, including the Great Western Divide
Great Western Divide
The Great Western Divide is a Sierra Nevada mountain range that forms part of the border between the Kings Canyon and Sequoia National Parks. The High Sierra Trail crosses the range at Kaweah Gap from Sequoia National Park.- References :...
. Use of this trail is discouraged during thunderstorm
Thunderstorm
A thunderstorm, also known as an electrical storm, a lightning storm, thundershower or simply a storm is a form of weather characterized by the presence of lightning and its acoustic effect on the Earth's atmosphere known as thunder. The meteorologically assigned cloud type associated with the...
s and when it is snowing.
Recreation
The road to Moro Rock is closed in winter, so visitors need to hike 2 miles to reach the viewpoint. The road is open in summer so the hike is shortened. The 1996 general plan for the park calls for the road to Moro to be closed, and replaced by a shuttle. As of 2011, the shuttle is running, but the road is not yet closed. The west face of Moro Rock offers 1,000 vertical feet of cracks and knobs for rock climbingRock climbing
Rock climbing also lightly called 'The Gravity Game', is a sport in which participants climb up, down or across natural rock formations or artificial rock walls. The goal is to reach the summit of a formation or the endpoint of a pre-defined route without falling...
. However, climbing is prohibited during peregrine falcon
Peregrine Falcon
The Peregrine Falcon , also known as the Peregrine, and historically as the Duck Hawk in North America, is a widespread bird of prey in the family Falconidae. A large, crow-sized falcon, it has a blue-gray back, barred white underparts, and a black head and "moustache"...
nesting season.
Geology
Moro Rock is a dome-shaped granite monolithMonolith
A monolith is a geological feature such as a mountain, consisting of a single massive stone or rock, or a single piece of rock placed as, or within, a monument...
. Common in the Sierra Nevada, these domes form by exfoliation
Exfoliation (geology)
Exfoliation joints or sheet joints are surface-parallel fracture systems in rock often leading to erosion of concentric slabs.- General characteristics of exfoliation joints :* Commonly follow topography ....
, the spall
Spall
Spall are flakes of a material that are broken off a larger solid body and can be produced by a variety of mechanisms, including as a result of projectile impact, corrosion, weathering, cavitation, or excessive rolling pressure...
ing or casting off in scales, plates, or sheets of rock layers on otherwise unjointed granite. Outward expansion of the granite results in exfoliations. Expansion results from load relief; when the overburden that once capped the granite has eroded away, the source of compression is removed and the granite slowly expands. Fractures that form during exfoliation tend to cut corners. This ultimately results in rounded dome-like forms.