Salinian Block

Salinian Block granite at Point Lobos

The Salinian Block or Salinian terrane is a geologic terrane which lies west of the main trace of the San Andreas Fault system in California. It is bounded on the south by the Big Pine Fault in Ventura County, and on the west by the Nacimiento Fault. The block was named for the Salinas Valley in Monterey County, California.

Geology

The Salinian Block is largely granitic, in accordance with its continental crustal origin. This contrasts sharply, and paradoxically, with much of the crust to its east, which is sedimentary and oceanic in origin. The block's granitic core, fragments of the batholith of the Peninsular Ranges, shares its origins with the Sierra Nevada Mountains.

During the past 30 Ma the North American Plate overrode the East Pacific Rise and complex transform faulting along the developing San Andreas fault zone sliced successive slivers of the Sierra Nevada - Peninsular batholith, moving the "stretched out" slices to the northwest to their current location.^[1] The granitic plutons of the Salinas block stretch from Bodega Head (38°18′39.6″N 123°03′57.6″W / 38.311000°N 123.066000°W / 38.311000; -123.066000) in the north to Mount Pinos (34°48′46.1″N 119°08′43.4″W / 34.812806°N 119.145389°W / 34.812806; -119.145389) at the southern end of the block.

The connection to the southern Sierra Nevada has been questioned in the years since the 1974 study by Johnson and Normark. "...[I]t more nearly resembles granite in the Mojave Desert". ^[2]

Features

Today, northern portions of the block are visible as Bodega Head, Point Reyes, the Farallon Islands, and the picturesque coastal scenery of the Monterey Peninsula, exemplified at Point Lobos and Pebble Beach.

References

↑ Jeffrey D. Johnson and William R. Normark, Neogene Tectonic Evolution of the Salinian Block, West-Central California, Geology 1974;2;11-14
↑ Alt, David; Hyndman, Donald W. (2000), Roadside Geology of Northern and Central California, Missoula: Mountain Press, p. 176

External links

Marin College: "Feldspar Staining of the Plutonic Rocks of the Salinian Terrane"

Seismically active fault zones and tectonic blocks of California

Statewide Faults	San Andreas Fault

Faults, zones, and blocks of Southern California	Brawley Seismic Zone Chino Fault Elsinore Fault Zone Elysian Park Fault Garlock Fault Hosgri Fault Imperial Fault Zone Laguna Salada Fault Newport–Inglewood Fault Peninsular Ranges Puente Hills Fault Raymond Fault Rose Canyon Fault Salton Trough Salinian Block San Cayetano Fault San Felipe Fault Zone San Gabriel Fault San Jacinto Fault Zone Santa Maria River Fault Santa Ynez Fault Shoreline Fault Ventura Fault White Wolf Fault Whittier Fault Yorba Linda Fault

Faults and zones of Northern California	Bartlett Springs Fault Calaveras Fault Clayton-Marsh Creek-Greenville Fault Concord Fault Hayward Fault Zone Healdsburg Fault Maacama Fault Mendocino Fracture Zone Mendocino Triple Junction Mount Diablo Thrust Fault Monta Vista Fault Pleasanton Fault San Gregorio Fault San Pablo Fault Seal Cove Fault Serra Fault Silver Creek Fault Tesla Fault West Napa Fault

Sierra Nevada faults, zones, and blocks	Death Valley Fault Zone Furnace Creek Fault Zone Honey Lake Fault Zone Kern Canyon Fault Maria fold and thrust belt Owens Valley Fault Rescue Lineament-Bear Mountains fault zone Sierra Nevada Batholith Sierra Nevada Fault Sierra Nevada-Great Valley Block Smartville Block Walker Lane

Category California Geological Survey Seismic Hazards Mapping Act Mexico (list)

Coordinates: 36°24′17.9″N 121°29′31.8″W / 36.404972°N 121.492167°W / 36.404972; -121.492167

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