The Intrusive Suite of Sonora Pass (also, the Sonora Pass Intrusive Suite) is one of several intrusive suites in

Yosemite National Park Yosemite National Park ( ) is a List of national parks of the United States, national park of the United States in California. It is bordered on the southeast by Sierra National Forest and on the northwest by Stanislaus National Forest. The p ...

. These also include # Fine Gold Intrusive Suite # Intrusive Suite of Buena Vista Crest # Intrusive Suite of Jack Main Canyon # Intrusive Suite of Merced Peak #

Intrusive Suite of Yosemite Valley The Intrusive Suite of Yosemite Valley (see Yosemite Valley) is one of several intrusive suites in Yosemite National Park. These also include # Fine Gold Intrusive Suite # Intrusive Suite of Buena Vista Crest # Intrusive Suite of Jack Main ...

Tuolumne Intrusive Suite The Tuolumne Intrusive Suite is the youngest and most extensive of the intrusive suites of Yosemite National Park, and also comprises about 1/3 of the park's area. The Suite includes Half Dome Granodiorite, Cathedral Peak Granite, and Kuna Cr ...

The Intrusive Suite of Sonora Pass is ~92-89 Ma, and is the northernmost of four large

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''cre ...

zoned intrusive suites in the central

Sierra Nevada batholith The Sierra Nevada Batholith is a large batholith that is approximately 400 miles long and 60-80 miles wide which forms the core of the Sierra Nevada mountain range in California, exposed at the surface as granite. The batholith is composed of ...

Rock types

On a large scale, it is composed of Kinney Lakes granodiorite and the younger Topaz Lake granodiorite. On a finer scale, the Intrusive Suite of Sonora Pass is made of light-gray, coarse-grained biotite granodiorite, plus

granite Granite ( ) is a coarse-grained (phanerite, phaneritic) intrusive rock, intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly coo ...

with roughly

equant Equant (or punctum aequans) is a mathematical concept developed by Claudius Ptolemy in the 2nd century AD to account for the observed motion of the planets. The equant is used to explain the observed speed change in different stages of the plane ...

, well-formed potassium feldspar

phenocryst image:montblanc granite phenocrysts.JPG, 300px, Granites often have large feldspar, feldspathic phenocrysts. This granite, from the Switzerland, Swiss side of the Mont Blanc massif, has large white phenocrysts of plagioclase (that have trapezoid sh ...

s composing about 2–10% of the rock.

Quartz Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The Atom, atoms are linked in a continuous framework of SiO4 silicon–oxygen Tetrahedral molecular geometry, tetrahedra, with each oxygen being shared between two tet ...

usually occurs in clots of . The

mafic A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron. Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite. Common mafic rocks include ...

mineral content is about 10%.

References

External links

A Masters thesis
Geology of California Geology of Yosemite National Park {{US-geology-stub