Intrusive Suite of Sonora Pass | |
---|---|
Stratigraphic range: Late Cretaceous, | |
Type | Suite |
Location | |
Region | Yosemite National Park |
Country | United States |
Type section | |
Named for | Sonora Pass |
The Intrusive Suite of Sonora Pass is visible, in light red |
The Intrusive Suite of Sonora Pass (also, the Sonora Pass Intrusive Suite) is one of several intrusive suites in Yosemite National Park. These also include
The Intrusive Suite of Sonora Pass is ~92-89 Ma, and is the northernmost of four large Late Cretaceous zoned intrusive suites in the central Sierra Nevada batholith. [1]
On a large scale, it is composed of Kinney Lakes granodiorite and the younger Topaz Lake granodiorite. [2]
On a finer scale, the Intrusive Suite of Sonora Pass is made of light-gray, coarse-grained biotite granodiorite, plus granite with roughly equant, well-formed potassium feldspar phenocrysts composing about 2–10% of the rock. Quartz usually occurs in clots of 0.5 centimetres (0.20 in). The mafic mineral content is about 10%. [3]
A batholith is a large mass of intrusive igneous rock, larger than 100 km2 (40 sq mi) in area, that forms from cooled magma deep in Earth's crust. Batholiths are almost always made mostly of felsic or intermediate rock types, such as granite, quartz monzonite, or diorite.
The exposed geology of the Yosemite area includes primarily granitic rocks with some older metamorphic rock. The first rocks were laid down in Precambrian times, when the area around Yosemite National Park was on the edge of a very young North American continent. The sediment that formed the area first settled in the waters of a shallow sea, and compressive forces from a subduction zone in the mid-Paleozoic fused the seabed rocks and sediments, appending them to the continent. Heat generated from the subduction created island arcs of volcanoes that were also thrust into the area of the park. In time, the igneous and sedimentary rocks of the area were later heavily metamorphosed.
Cathedral Peak is part of the Cathedral Range, a mountain range in the south-central portion of Yosemite National Park in eastern Mariposa and Tuolumne Counties. The range is an offshoot of the Sierra Nevada. The peak which lends its name to the range derives its name from its cathedral-shaped peak, which was formed by glacial activity: the peak remained uneroded above the glaciers in the Pleistocene.
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 Kern Canyon Fault is a dextral strike-slip fault (horizontal) that runs roughly around 150 km (93 mi) beside the Kern River Canyon through the mountainous area of the Southern Sierra Nevada Batholith. The fault was a reverse fault in the Early Cretaceous epoch during the primal stages of the Farallon Plate subduction beneath the North American Continental Plate and fully transitioned into a strike-slip shear zone during the Late Cretaceous.
The Cathedral Peak Granodiorite (CPG) was named after its type locality, Cathedral Peak in Yosemite National Park, California. The granodiorite forms part of the Tuolumne Intrusive Suite, one of the four major intrusive suites within the Sierra Nevada. It has been assigned radiometric ages between 88 and 87 million years and therefore reached its cooling stage in the Coniacian.
Vogelsang Pass is a mountain pass in the Cathedral Range of Yosemite National Park, at 10,680 ft (3,260 m). It lies between the cirque containing Vogelsang Lake and the valley with Lewis Creek. The pass also lies on the ridge between Fletcher Peak and Vogelsang Peak.
The Idaho Batholith is a granitic and granodioritic batholith of Cretaceous-Paleogene age that covers approximately 25,000 square kilometres (9,700 sq mi) of central Idaho and adjacent Montana. The batholith has two lobes that are separate from each other geographically and geologically. The Bitterroot lobe is the smaller lobe and the larger lobe is the Atlanta lobe. The Bitterroot lobe is in the north and is separated from the larger Atlanta lobe in the south by the Belt Supergroup metamorphic rocks that compose the Salmon River Arch. Much of the Atlanta and Bitterroot lobes are in the Idaho Batholith ecoregion.
Half Dome Granodiorite is granodiorite found in a region on and near Half Dome, in Yosemite National Park, California, United States. The granodiorite forms part of the Tuolumne Intrusive Suite, one of the four major intrusive suites within the Sierra Nevada.
El Capitan Granite is a type of granite, in a large area near El Capitan, in Yosemite National Park, California, United States. The granite forms part of the Tuolumne Intrusive Suite, one of the four major intrusive suites within the Sierra Nevada.
Kuna Crest Granodiorite, is found, in Yosemite National Park, United States. The granodiorite forms part of the Tuolumne Intrusive Suite, one of the four major intrusive suites within the Sierra Nevada. Of the Tuolumne Intrusive Suite, it is the oldest and darkest rock.
Sentinel granodiorite is a type of granodiorite found in Yosemite National Park. It is a poorly understood western "outlier" of the ~93-85-Ma Tuolumne Intrusive Suite of the Sierra Nevada batholith. It is only slightly older than the undated Yosemite Creek Granodiorite and the Kuna Crest Granodiorite.
Mokelumne Peak is a peak in the Mokelumne Wilderness, Sierra Nevada, Amador County, California, consisting of metamorphic and granitic rock.
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 Crest Granodiorite.
The Fine Gold Intrusive Suite is one of several intrusive suites that crosses into Yosemite National Park. These also include
The Intrusive Suite of Buena Vista Crest is an intrusive suite which extends 30 kilometres (19 mi) southward, from Yosemite Valley to Yosemite National Park's southeastern boundary, into plutons of the Sierra Nevada Batholith, which are slightly older. These intrusive suites also include
The Intrusive Suite of Yosemite Valley is one of several intrusive suites in Yosemite National Park. These also include
Mammoth Peak is a mountain in the area of Tuolumne Meadows, Yosemite National Park, California. The summit is a class 1-2 cross-country hike that features river crossings and boulder scrambling. The peak lies at the northern end of the Kuna Crest and is close to California State Route 120. From the road, its summit appears rounded and quite rocky. Though Mammoth Peak is not as popular as other nearby peaks, its relatively easily accessed summit affords tremendous views of Mount Gibbs, Mount Dana, and Mount Lewis.
The Intrusive Suite of Merced Peak is one of several intrusive suites in Yosemite National Park. These also include:
Johnson Granite Porphyry is found in Tuolumne Meadows, Yosemite National Park.