Coast Range Geomorphic Province
Encyclopedia
The Coast Range Geomorphic Province is a portion of coastal California
, United States
. This orogen geomorphic province constitutes a barrier between the Pacific Ocean
and the San Joaquin Valley
which trends northwest from Point Conception
to the border with Oregon
, with a significant break in the San Francisco Bay Area
by the basins of the Sacramento River
and San Joaquin River
that discharge into the Pacific. The province consists of mountain range
s and the corresponding valley
s and basins.
The San Francisco Bay Area naturally subdivides the province into the North Coast Ranges and South Coast Ranges.
The province is formed as an interaction between the North American
and Pacific
tectonic plates. The Pacific Plate moves northwest relatively to the North American one with speed of about 35-38 mm/year, with the majority of motion occurring during large earthquake
s, with some aseismic fault creep. The overlap of the plates is about 100 km wide and contains all major geologic fault
s of the Northern California
. The mountain ranges of the province are composed primarily of late Mesozoic
(200 to 70 million years old) Cenozoic
(less than 70 million years old) sedimentary strata.
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
, United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. This orogen geomorphic province constitutes a barrier between the Pacific Ocean
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
and the San Joaquin Valley
San Joaquin Valley
The San Joaquin Valley is the area of the Central Valley of California that lies south of the Sacramento – San Joaquin River Delta in Stockton...
which trends northwest from Point Conception
Point Conception
Point Conception is a headland along the Pacific coast of U.S. state of California, located in southwestern Santa Barbara County. It is the point where the Santa Barbara Channel meets the Pacific Ocean, and as the corner between the mostly north-south trending portion of coast to the north and the...
to the border with Oregon
Oregon
Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...
, with a significant break in the San Francisco Bay Area
San Francisco Bay Area
The San Francisco Bay Area, commonly known as the Bay Area, is a populated region that surrounds the San Francisco and San Pablo estuaries in Northern California. The region encompasses metropolitan areas of San Francisco, Oakland, and San Jose, along with smaller urban and rural areas...
by the basins of the Sacramento River
Sacramento River
The Sacramento River is an important watercourse of Northern and Central California in the United States. The largest river in California, it rises on the eastern slopes of the Klamath Mountains, and after a journey south of over , empties into Suisun Bay, an arm of the San Francisco Bay, and...
and San Joaquin River
San Joaquin River
The San Joaquin River is the largest river of Central California in the United States. At over long, the river starts in the high Sierra Nevada, and flows through a rich agricultural region known as the San Joaquin Valley before reaching Suisun Bay, San Francisco Bay, and the Pacific Ocean...
that discharge into the Pacific. The province consists of mountain range
Mountain range
A mountain range is a single, large mass consisting of a succession of mountains or narrowly spaced mountain ridges, with or without peaks, closely related in position, direction, formation, and age; a component part of a mountain system or of a mountain chain...
s and the corresponding valley
Valley
In geology, a valley or dale is a depression with predominant extent in one direction. A very deep river valley may be called a canyon or gorge.The terms U-shaped and V-shaped are descriptive terms of geography to characterize the form of valleys...
s and basins.
The San Francisco Bay Area naturally subdivides the province into the North Coast Ranges and South Coast Ranges.
The province is formed as an interaction between the North American
North American Plate
The North American Plate is a tectonic plate covering most of North America, Greenland, Cuba, Bahamas, and parts of Siberia, Japan and Iceland. It extends eastward to the Mid-Atlantic Ridge and westward to the Chersky Range in eastern Siberia. The plate includes both continental and oceanic crust...
and Pacific
Pacific Plate
The Pacific Plate is an oceanic tectonic plate that lies beneath the Pacific Ocean. At 103 million square kilometres, it is the largest tectonic plate....
tectonic plates. The Pacific Plate moves northwest relatively to the North American one with speed of about 35-38 mm/year, with the majority of motion occurring during large earthquake
Earthquake
An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...
s, with some aseismic fault creep. The overlap of the plates is about 100 km wide and contains all major geologic fault
Geologic fault
In geology, a fault is a planar fracture or discontinuity in a volume of rock, across which there has been significant displacement along the fractures as a result of earth movement. Large faults within the Earth's crust result from the action of tectonic forces...
s of the Northern California
Northern California
Northern California is the northern portion of the U.S. state of California. The San Francisco Bay Area , and Sacramento as well as its metropolitan area are the main population centers...
. The mountain ranges of the province are composed primarily of late Mesozoic
Mesozoic
The Mesozoic era is an interval of geological time from about 250 million years ago to about 65 million years ago. It is often referred to as the age of reptiles because reptiles, namely dinosaurs, were the dominant terrestrial and marine vertebrates of the time...
(200 to 70 million years old) Cenozoic
Cenozoic
The Cenozoic era is the current and most recent of the three Phanerozoic geological eras and covers the period from 65.5 mya to the present. The era began in the wake of the Cretaceous–Tertiary extinction event at the end of the Cretaceous that saw the demise of the last non-avian dinosaurs and...
(less than 70 million years old) sedimentary strata.