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: 1,119
February 23, 2006

PubTalk 2/2006 — Science and Natural Resources along La Frontera

By Floyd Gray, Geologist

  • Natural systems-water, geology, and wildlife-tend to cross the 1,900- mile-long arbitrary political border between Mexico and the U.S.
  • Rapid population growth on the U.S. side and in Mexican border cities is creating a variety of environmental, ecological, and human health problems
  • The San Pedro River
Satellite image showing fire in California.
February 12, 2006

Southern California Wildfires, USA - 2006

These images show the nearly 11,000 acres affected by the Sierra fire in Orange County, California, in February 2006.

Andrew Schwartz and Dan Hanes hold a current profiler for a study of surf-zone hydrodynamics at Ocean Beach, San Francisco.
January 30, 2006

Studying Surf-Zone Hydrodynamics

USGS scientists Andrew Schwartz and Dan Hanes maneuver a current profiler for a study of surf-zone hydrodynamics at Ocean Beach, on the west side of San Francisco, California. Beach erosion has been a continuing problem in this area. This fieldwork is part of an effort to document, analyze, and simulate the processes that control sand transport and sedimentation patterns

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January 26, 2006

PubTalk 1/2006 — Serving California's Needs

HOW THE CALIFORNIA GEOLOGICAL SURVEY IDENTIFIES AND MAPS NATURAL HAZARDS, PROMOTES THE STATE'S ECONOMY, AND PROTECTS PUBLIC HEALTH AND SAFETY

By George J. Saucedo and Keith L. Knudson, Geologists

  • Hear about the rich and productive 125-year history of the California Geological Survey (CGS)
  • Major emphases of CGS work are mapping
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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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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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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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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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
Filter Total Items: 992
USGS
October 21, 1999

Recent devastating earthquakes have impacted Turkey, Taiwan, and Mexico. If the epicenter of last weeks 7.1 Hector earthquake in the Mojave Desert had occurred 100 miles to the east or to the west, Las Vegas or Los Angeles would still be picking up the pieces.

USGS
October 19, 1999

White abalone - 1,000 to 5,000 per acre - were easy to find in the early 1970s around the Channel Islands off California’s southern coast. But by the late 1970s, intense commercial and recreational harvesting made the abalone as difficult to locate a needle in an ocean-sized haystack.

USGS
October 14, 1999

There is a 70 percent probability that one or more damaging earthquakes of magnitude 6.7 or larger will strike the San Francisco Bay area during the next 30 years, according to a report released today (Oct. 14, 1999) by the U.S. Geological Survey. A magnitude 6.7 earthquake is equivalent to the 1994 Northridge earthquake which killed 57 people and caused $20 billion in damage.

USGS
October 8, 1999

A new set of maps from the U.S. Geological Survey explains in depth, literally, more than 30,000 earthquakes that occurred in north-central California between 1967 and 1993. That time frame, of course, includes the largest earthquake to occur in the area since 1906, the 1989, 6.9 Loma Prieta earthquake.

USGS
October 8, 1999

When is a badly damaged, but stable building safe to enter after an earthquake? That is a question that safety-response and building-department officials have to answer in order to let occupants retrieve important possessions and business records, and to let contractors begin emergency repairs

USGS
October 5, 1999

When their offices and homes began shaking at 5:04 p.m., Oct. 17, 1989, earthquake scientists at the U.S. Geological Survey in Menlo Park, Calif., were as surprised as anyone.

USGS
October 5, 1999

With a press run of more than three million copies, "The Next Big Earthquake In The Bay Area May Come Sooner Than You Think-- Are You Prepared?" is the most widely distributed publication ever prepared by the U.S. Geological Survey. Nine years after it’s publication, it is still available from the USGS, and still helpful as a preparedness guide for Bay Area residents.

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.