Cathedral Peak is part of the Cathedral Range, a mountain range in the south-central portion of

Yosemite National Park Yosemite National Park ( ) is an American national park in California, surrounded on the southeast by Sierra National Forest and on the northwest by Stanislaus National Forest. The park is managed by the National Park Service and covers an ...

in eastern Mariposa and Tuolumne Counties. The range is an offshoot of the

Sierra Nevada The Sierra Nevada () is a mountain range in the Western United States, between the Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primari ...

. The peak which lends its name to the range derives its name from its

cathedral A cathedral is a church that contains the ''cathedra'' () of a bishop, thus serving as the central church of a diocese, conference, or episcopate. Churches with the function of "cathedral" are usually specific to those Christian denominatio ...

-shaped peak, which was formed by

glacial A glacial period (alternatively glacial or glaciation) is an interval of time (thousands of years) within an ice age that is marked by colder temperatures and glacier advances. Interglacials, on the other hand, are periods of warmer climate betwe ...

activity: the peak remained uneroded above the glaciers in the

Pleistocene The Pleistocene ( , often referred to as the '' Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed ...

Geography

Cathedral Peak has a subsidiary summit to the west called Eichorn Pinnacle, for Jules Eichorn, who first ascended a class 5.4 route to its summit on July 24, 1931, with

Glen Dawson Glen Dawson may refer to: * Glen Dawson (athlete) (1906–1968), American steeplechase runner * Glen Dawson (mountaineer) Glen Dawson (June 3, 1912 – March 22, 2016) was an American rock climber, mountaineer, antiquarian bookseller, publisher ...

. In 1869,

John Muir John Muir ( ; April 21, 1838December 24, 1914), also known as "John of the Mountains" and "Father of the National Parks", was an influential Scottish-American naturalist, author, environmental philosopher, botanist, zoologist, glaciologist ...

wrote in ''My first summer in the Sierra'': CathedralPeakCA

Geology

The Cathedral Peak Granodiorite of Cathedral Peak is an

intrusion In geology, an igneous intrusion (or intrusive body or simply intrusion) is a body of intrusive igneous rock that forms by crystallization of magma slowly cooling below the surface of the Earth. Intrusions have a wide variety of forms and com ...

into an area of older intrusive (or plutonic) and metamorphic rock in the

Sierra Nevada Batholith The Sierra Nevada Batholith is a large batholith which forms the core of the Sierra Nevada mountain range in California, exposed at the surface as granite. The batholith is composed of many individual masses of rock called '' plutons'', which f ...

. It is part of a grouping of intrusions called the Tuolumne Intrusive Suite. Cathedral Peak is the youngest of the rock formations in the Suite, dating to the

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ...

Period at 83 million years ago. Its composition is mainly

granodiorite Granodiorite () is a coarse-grained ( phaneritic) intrusive igneous rock similar to granite, but containing more plagioclase feldspar than orthoclase feldspar. The term banatite is sometimes used informally for various rocks ranging from gr ...

with

phenocryst 300px, Swiss side of the Mont Blanc massif, has large white plagioclase phenocrysts, triclinic minerals that give trapezoid shapes when cut through). 1 euro coins, 1 euro coin (diameter 2.3 cm) for scale. A phenocryst is an early forming, relati ...

s of

microcline Microcline (KAlSi3O8) is an important igneous rock-forming tectosilicate mineral. It is a potassium-rich alkali feldspar. Microcline typically contains minor amounts of sodium. It is common in granite and pegmatites. Microcline forms during slow ...

. Cathedral Peak was a nunatak during the Tioga glaciation of the last ice age, the peak projected above the

glaciers A glacier (; ) is a persistent body of dense ice that is constantly moving under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It acquires distinguishing features, such a ...

, which carved and sharpened the peak's base while plucking away at its sides.

References

External links

* {{Authority control Geology of Yosemite National Park Mountains of Yosemite National Park Mountains of Mariposa County, California Mountains of Tuolumne County, California Igneous intrusions Mountains of Northern California Cretaceous magmatism Igneous petrology of California

Geography

Geology

See also

References

External links