Unified Interior Regions

California

The Southwest Region includes California, Nevada, and Arizona. The Regional Office, headquartered in Sacramento, provides Center oversight and support, facilitates internal and external collaborations, and works to further USGS strategic science directions.

States L2 Landing Page Tabs

Filter Total Items: 1,121
3-D angular view of a bay inlet with a bridge spanning the inlet, the floor of the bay is shown as if the water is drained out.
December 31, 2005

Sand waves at mouth of San Francisco Bay

A field of giant sand waves, among the largest in the world, at the mouth of San Francisco Bay in California. This massive bed form field covers an area of approximately four square kilometers in water depths ranging from 30 to 106 meters, featuring more than 40 distinct sand waves with crests aligned approximately perpendicular to the dominant tidally generated cross-

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long fissure in the dry Mojave Desert with the mountains in the background
December 31, 2005

Fissure in the Mojave Desert

Fissure near Lucerne Lake along State Route 247 (visible in background), Mojave Desert, California. The localized subsidence in five areas near dry lake beds was caused by declining water levels in fine-grained (clay and silt) sediments. In the Mojave River and Morongo Groundwater Basins (fig. 2), the combination of variable climatic conditions, tectonic activity, and

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Poster laid out with photos, images, and text.
December 31, 2005

Should Englebright Dam Be Removed?

Large-scale poster describing USGS work.

The USGS, in cooperation with the Upper Yuba River Studies Program and the California Bay–Delta Authority (CALFED), studied Englebright Lake. Englebright Dam was built in 1941 to trap sediment washed downstream by hydraulic gold mining.

We used sonar to map the lake and took sediment cores from the lake bottom. By

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Map of the known ash-fall boundaries for several U.S. eruptions
December 31, 2005

Map of the known ash-fall boundaries for several U.S. eruptions

Eruptions of the Yellowstone volcanic system have included the two largest volcanic eruptions in North America in the past few million years; the third largest was at Long Valley in California and produced the Bishop ash bed. The biggest of the Yellowstone eruptions occurred 2.1 million years ago, depositing the Huckleberry Ridge ash bed. These eruptions left behind huge

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Map of land subsidence in the Sacramento-San Joaquin Delta, shaded by feet below sea level
December 31, 2005

Sacramento-San Joaquin Delta Land Subsidence

A map of subsidence in the Delta based on the leveling and observations of transmission-line foundations, circa 1930s-1990s. The subsidence increases stresses on the levee system, and failure of levees would cause salt water to move further up the Delta system by disrupting favorable gradients. This would degrade the quality of water that is the heart of water supply

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Image: Pacific Coast of California
December 31, 2005

Pacific Coast of California

Waves crashing against rocks off the Pacific coast of California.

Attribution: Water Resources
Image: Pacific Coast of California
December 31, 2005

Pacific Coast of California

Waves crashing against rocks off the Pacific coast of California.

Attribution: Water Resources
December 8, 2005

PubTalk 12/2005 — Frozen in Time

How Ice Cores Are Revealing the Composition and Temperature of Earth's Atmosphere During the Past Million Years

by Todd Hinkley, Geologist

 

  • Scientifically invaluable ice cores taken from Antarctic and Arctic ice are stored and safe guarded at the U.S. National Ice Core Laboratory, operated by the U.S. Geological Su rvey
November 17, 2005

PubTalk 11/2005 — Shifting Shoals and Shattered Rocks

HOW MAN HAS CHANGED THE FLOOR OF SAN FRANCISCO BAY

by John Chin and Florence Wong, Geologists

 

  • San Francisco Bay is one of the world's finest natural harbors and a major center of maritime trade
  • All ships visiting bay ports are funneled through the central bay
  • Bedrock knobs that rise from the central
October 27, 2005

PubTalk 10/2005 – Earthquake Storms

The Very Long Reach of Very Large Earthquakes

by Susan Hough, Seismologist

 

  • How did the 1992 Landers quake in the remote Mojave Desert change scientists' thinking about earthquake sequences?
  • What is the explanation for "aftershocks" of the 1906 San Francisco earthquake reported in Arizona?
  • How do large
Image: Greater Roadrunner (Geococcyx californianus)
October 24, 2005

Greater Roadrunner (Geococcyx californianus)

A roadrunner at the base of a old volcanic rock, near a trail in Petroglyph National Monument.

Attribution: Ecosystems
October 21, 2005

PubTalk 10/2005 — A Crack in the Edge of the World

America and the Great California Earthquake of 1906

by Simon Winchester

 

  • The international bestselling author of The Professor and the Madman and Kra katoa vividly brings to life the 1906 San Francisco Earthquake that leveled a city symbolic of America's relentless western expansion. Simon Winchester
Filter Total Items: 973
USGS
July 28, 1999

A new screening method, based on geology and climatology, has been shown to be a reliable means for predicting where lands in irrigated areas are susceptible to contamination from selenium, according to a report by the U.S. Geological Survey (USGS), in cooperation with the U.S. Fish and Wildlife Service, Bureau of Reclamation, and Bureau of Indian Affairs.

USGS
July 27, 1999

The USGS scientist who intrigued Ted Kennedy Jr., Tuesday, with her foot-and voice-operated computer/microscope, will give interviews and demonstrations again Wednesday, during the second day of the USGS’s seventh annual Conference on Addressing the Employment of People with Disabilities, on the USGS campus in Menlo Park.

USGS
July 26, 1999

Some employees at the U.S. Geological Survey in Menlo Park don’t wait for an annual "take your dog to work" day; they do it every day. Like the USGS human roster, some of the dogs are still in training, while others have graduate degrees and are now gainfully and fully employed.

USGS
July 19, 1999

A drilling project that is harvesting 1,000 feet of earth and rock cores from the Los Angeles basin will establish a virtual library of information on the geology of the area, according to scientists from the U.S. Geological Survey (USGS).

USGS
July 13, 1999

Providing a plan to help resource managers restore the Bering Sea and North Pacific ecosystem is a task research scientist Jim Estes of the U.S. Geological Survey will pursue during the next four years with funding help from a 1999 Pew Marine Conservation fellowship of $150,000.

USGS
June 10, 1999

It is well known that fire suppression in forests has led to an increase in catastrophic forest fires. The same has been assumed to be true for fire suppresion in shrublands. However, a recent USGS study has found that urban sprawl -- not fire suppression -- is largely responsible for the wildfires that occur in the shrublands of southern and central-coastal California.

USGS
May 12, 1999

Maps and other products of the U.S. Geological Survey will be on display,for sale and as free handouts, at the USGS booth at the Sunset Magazine open house, this weekend, May 15 and 16.

USGS
April 30, 1999

The source of tarballs in the Monterey Bay National Marine Sanctuary, new views of the seafloor of Monterey Bay and new data on the San Gregorio fault are the focus of three presentations by U.S. Geological Survey scientists at the Pacific Section Meeting of the American Association of Petroleum Geologists, in Monterey.

USGS
April 23, 1999

As United States Geological Survey (USGS) researchers skim the surface of the ocean in a small boat near Long Beach, a new never-before-seen view of Los Angeles is revealed.

USGS
March 26, 1999

U.S. Geological Survey scientists of the Western Ecological Research Center will report on the effects of exotic animals on native plants in Channel Islands National Park at the 5th California Islands Symposium, in Santa Barbara, Calif., Mar. 29-Apr. 1.

USGS
March 11, 1999

Chemical contamination in San Francisco Bay has decreased since enactment of the Clean Water Act in 1970, but the bay is still suffering from "contaminant stress," according to a a U.S. Geological Survey chemist who has been analyzing the bay’s waters for 30 years.

USGS
January 21, 1999

From the Gold Rush of 1849 through the 1960’s, California produced about 3,300 tons of gold, or about one-third of all U.S. gold production, but it left a legacy of detrimental environmental effects whose damage may never be fully determined, according to Roger Ashley of the U.S. Geological Survey in Menlo Park, Calif.