El Capitan Granite

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El Capitan Granite
Stratigraphic range: 103 Ma
ElCapitan.jpg
Type Geological formation
Unit of Tuolumne Intrusive Suite
Location
LocationCalifornia
Country United States
Type section
Named for El Capitan
A geologic map of Yosemite National Park Map of Cathedral Peak Granodiorite.svg
A geologic map of Yosemite National Park

El Capitan Granite is a type of granite (also see granodiorite), in a large area near El Capitan, in Yosemite National Park, California, United States. The granite forms part of the Tuolumne Intrusive Suite (also known as Tuolumne Batholith), one of the four major intrusive suites within the Sierra Nevada.

Contents

El Capitan granite is mostly unjointed. [1]

Composition

El Capitan Granite Rectangular blocks formed in the EI Capitan Granite California.jpg
El Capitan Granite

The granite has abundant quartz, plagioclase, crystals of orthoclase, and both feldspars orthoclase and plagioclase are white. Hornblende is rare, compared to other Yosemite granites. Most black minerals are biotite. [2]

Location

It is found west of Half Dome Granodiorite, both north and south, to a western limit near Cookie Cliffs.

All of Turtleback Dome, El Capitan, The Three Brothers, and Cathedral Rocks are made of El Capitan Granite [3] as is Elephant Rock. [4]

El Capitan Granite makes up most of the granite found in the west half of the Yosemite Valley area. [5]

Age

El Capitan Granite intruded older plutonic rocks about 103 Ma, [3] during the Cretaceous Period.

See also

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  2. Intrusive Suite of Jack Main Canyon
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  2. Intrusive Suite of Buena Vista Crest
  3. Intrusive Suite of Jack Main Canyon
  4. Intrusive Suite of Merced Peak
  5. Intrusive Suite of Sonora Pass
  6. Tuolumne Intrusive Suite
  7. Johnson Granite Porphyry
<span class="mw-page-title-main">Intrusive Suite of Sonora Pass</span> Intrusive Suite of Sonora Pass is one of several intrusive suites in Yosemite National Park

The Intrusive Suite of Sonora Pass is one of several intrusive suites in Yosemite National Park. These also include

  1. Fine Gold Intrusive Suite
  2. Intrusive Suite of Buena Vista Crest
  3. Intrusive Suite of Jack Main Canyon
  4. Intrusive Suite of Merced Peak
  5. Intrusive Suite of Yosemite Valley
  6. Tuolumne Intrusive Suite
<span class="mw-page-title-main">Intrusive Suite of Merced Peak</span> Intrusive Suite of Merced Peak is an intrusive suite, of Yosemite National Park

The Intrusive Suite of Merced Peak is one of several intrusive suites in Yosemite National Park. These also include:

  1. Fine Gold Intrusive Suite
  2. Intrusive Suite of Buena Vista Crest
  3. Intrusive Suite of Jack Main Canyon
  4. Intrusive Suite of Sonora Pass
  5. Intrusive Suite of Yosemite Valley
  6. Johnson Granite Porphyry
  7. Tuolumne Intrusive Suite

Johnson Granite Porphyry is found in Tuolumne Meadows, Yosemite National Park.

References

  1. N. King Huber and Julie A. Roller from the writings of Frank C. Calkins and other sources (1985). "Relation of Landforms to Rock Composition and Structure" . Retrieved 12 May 2016.
  2. Glazner, Allen F, Stock, Greg M. (2010). Geology Underfoot in Yosemite. Mountain Press, p. 45. ISBN   978-0-87842-568-6
  3. 1 2 N. King Huber and Julie A. Roller from the writings of Frank C. Calkins and other sources (1985). "Rocks of the Yosemite Valley Area" . Retrieved 12 May 2016.
  4. s (1 June 1985). "Roadside Geology of Yosemite Valleya" . Retrieved 12 May 2016.
  5. N. King Huber (1985). "Yosemite Valley area" . Retrieved 12 May 2016.