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: 421
Date published: October 21, 2016

USGS WERC Ecology Research Update: March 2016

USGS Western Ecological Research Center newsletters are posted on our blog. Check back for a rundown of new research and events on ecology and wildlife science in California and Nevada. 

Date published: August 1, 2016
Status: Active

Ecology of Insect-eating Bats

Bats are the only flying mammals that are active mostly at night and occur on all continents except Antarctica. Bats are ecologically diverse, with a range of species that specialize in feeding on fruit, nectar, blood, fish, small mammals, and insects. However, of the more than 1,100 known species of bats on Earth, the majority specialize in feeding on insects. In the United States for example...

Date published: July 26, 2016
Status: Active

HDgov: Multi-agency Website for Human Dimensions of Natural Resources

HDgov is an interactive and mobile-responsive online portal to interagency, academic, and non-government resources focused on the human dimensions of natural resource management. The web portal provides easy access to tools, publications, data, and methods that help ensure that the people side of natural resources is considered throughout the entire natural resource management process. The...

Date published: July 26, 2016
Status: Active

National Park Service Visitor Spending Effects

The National Park Service (NPS) manages the Nation’s most iconic destinations that attract millions of visitors from across the Nation and around the world. Trip-related spending by NPS visitors generates and supports a considerable amount of economic activity within park gateway communities. USGS economists collaborate with the National Park Service social science program to estimate NPS...

Date published: July 21, 2016
Status: Active

Using Quantile Regression to Investigate Ecological Limiting Factors

Unexplained heterogeneity in statistical models of animal responses to their physical environment is reasonable to expect because the measured habitat resources are a constraint on—but not the sole determinant of—abundance, survival, fecundity, or fitness. The ecological understanding and reliability of management predictions based on animal habitat models can be improved by shifting focus ...

Date published: July 21, 2016
Status: Active

North American Waterfowl Management Plan

The ultimate success of North American Waterfowl Management Plan (NAWMP) depends on maintaining relevance to stakeholders and society. In order to be relevant, a first step is to better understand what people value in regard to waterfowl and their habitats. 

Date published: July 19, 2016
Status: Completed

Quantitative and Statistical Research Collaboration

Mathematical and statistical models are powerful research tools that play several important roles in conceptualizing and understanding the structure and dynamics of complicated ecological systems, including developing mechanistic hypotheses pertaining to ecological systems, designing studies that elucidate ecosystem structure and function, and extracting information from data.

Date published: June 27, 2016
Status: Active

Using Cell Technology to Track Species Movement

The Information Science Branch explored and developed ways to track species locations using a standard cellular phone network. This technology provides more tracking data at a faster rate and lower cost than traditional satellite tracking systems. The initial implementation of this approach currently provides support for the California Condor recovery program and is being extended to include...

Contacts: Gail Montgomery
Date published: April 13, 2016

Understanding Coastal Change

Scientists perform a range of studies that document, assess, and model coastal change, risk, and vulnerability. Studies include historical shoreline change, the geologic structure and history of coastal regions, sediment supply and transport, sea-level rise, and how extreme storm events affect rates and impacts of coastal change.

Date published: April 13, 2016

Geologic Hazards and Catastrophic Events

We study the distribution and hazard potential of coastal and submarine events such as earthquakes and submarine landslides and associated tsunami potential, hurricane induced coastal inundation, extreme storms, sea-level rise and oil and gas spills. We also model development to help evaluate and forecast coastal hazard probability and occurrence.

Date published: April 13, 2016

Ocean Resources for America's Needs

Our scientists conduct research studies focused on geologic mapping, sampling and understanding of mineral and energy resources and studies of the geologic setting and processes to inform renewable energy development offshore.

Date published: April 12, 2016
Status: Active

USGS Library

The USGS Library, managed by CSAS&L, supports all fundamental scientific research conducted within USGS. It serves both internal and external customers with comprehensive access to literature, data, and information necessary understand USGS mission areas and make critical decisions about how to proceed with research initiatives and investigations in the earth and natural sciences.

Filter Total Items: 588
Date published: January 1, 2018

Acoustic backscatter data collected in 2007 from the San Miguel Passage in the Channel Islands, California

This portion of the data release presents acoustic backscatter data from the San Miguel Passage, in the Channel Islands, California. The data were collected in August 2007 by the U.S. Geological Survey, Pacific Coastal and Marine Science Center (USGS, PCMSC) using a 234.5 kHz SEA (AP) Ltd. SWATHplus-M phase-differencing sidescan sonar mounted on the NOAA, Channel Islands Nationa

Date published: January 1, 2018

Structure-from-Motion (SfM) surface models derived from seafloor video from the Channel Islands, California

Structure-from-Motion (SfM) surface models were created using seafloor video collected over a visible fault scarp in the Channel Islands, California, during a 2016 U.S. Geological Survey (USGS) field activity. Four SfM surface models were created, each with a different combination of locating, scaling, and optimizing methods. Video imagery was collected using the USGS Pacific Co

Date published: January 1, 2018

Grain size and bulk density of sediment cores from Little Holland Tract and Liberty Island, Sacramento-San Joaquin Delta, California, 2014

Grain size distribution and bulk density are reported for sediment push cores from two flooded agricultural tracts, Little Holland Tract and Liberty Island, in the Sacramento-San Joaquin Delta, California. Push core samples were collected from 14 sites by the U.S Geological Survey in August, 2014. Each core was analyzed at multiple depths to investigate variations in particle sizes with d

Date published: January 1, 2018

Photographs and video clips of Clear Lake Hitch (Lavinia exilicauda chi)

This data release includes a collection of photographs and video clips. Above water observations were taken with with a Nikon D5300 digital camera and underwater observations were taken with a SOOCOO S100Pro digital camera. All observations were made on April 1, 2018 in Kelsey, Creek, Lake County, California. Further details can be found in: Feyrer, F. 2018. Rapid potamodromy int

Date published: January 1, 2018

California Groundwater Ambient Monitoring and Assessment (GAMA) Program Priority Basin Project Study Areas and grid cells for assessment of groundwater resources used for public drinking-water supply.

The California Groundwater Ambient Monitoring and Assessment Program (GAMA) is a statewide, comprehensive assessment of groundwater quality designed to help better understand and identify risks to groundwater resources. GAMA is being implemented by the California State Water Resources Control Board. The USGS is the technical lead for the Priority Basin Project (PBP), one of the compon

Date published: January 1, 2018

Central Mojave Desert Vegetation Mapping Project, California, 1997-1999

The U.S. Geological Survey (USGS) Data at Risk (DaR) team partnered with the USGS Southwest Biological Science Center (SBSC) to preserve and release tabular data, shapefiles and field photographs of the Central Mojave Desert from 1997-1999. The data were originally collected as part of an effort through the Desert Managers Group (DMG) to develop scientific information on the dis

Date published: January 1, 2018

Geochemical and geophysical data for wells in the Fruitvale oil and gas field

The U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board compiled and analyzed data for the purpose of mapping groundwater salinity in selected oil and gas fields in California. The data for the Fruitvale and Rosedale Ranch oil fields include well construction data, digitized borehole geophysical data, geochemical analyses of water samples f

Date published: January 1, 2018

CoSMoS (Coastal Storm Modeling System) Southern California v3.0 Phase 2 wave-hazard projections: 1-year storm in Channel Islands

Model-derived significant wave height (in meters) for the given storm condition and sea-level rise (SLR) scenario.
The Coastal Storm Modeling System (CoSMoS) makes detailed predictions (meter-scale) over large geographic scales (100s of kilometers) of storm-induced coastal flooding and erosion for both current and future sea-level rise (SLR) scenarios. CoSMoS v3.0 for So

Date published: December 26, 2017

Hydrodynamic and sediment transport data from San Pablo Bay and China Camp marsh (northern San Francisco Bay), 2013-2016

The USGS Pacific Coastal and Marine Science Center collected data to investigate sediment dynamics in the shallows of San Pablo Bay (SP) and sediment exchange between bay shallows and the tidal salt marsh in China Camp State Park (CMC) in a series of deployments between December 2013 and June 2016. This data release includes two related groups of data sets, one for SP and one for CMC.

Date published: December 12, 2017

River-channel topography, grain size, and turbidity records from the Carmel River, California, before, during, and after removal of San Clemente Dam

The San Clemente Dam, built in the 1920s on the Carmel River in Monterey County, California, was removed during 2014 and 2015. The dam-removal project was the largest in California to date, and one of the largest in the U.S. The USGS collected data before, during, and after the removal of the dam to study how the river channel's topographic profiles and sediment distributions changed...

Date published: November 16, 2017

Multibeam bathymetry and acoustic-backscatter data collected in 2016 in Catalina Basin, southern California and merged multibeam bathymetry datasets of the northern portion of the Southern California Continental Borderland

In February 2016 the University of Washington in cooperation with USGS PCMSC collected multibeam bathymetry and acoustic-backscatter data in and near the Catalina Basin, southern California aboard the University of Washington's Research Vessel Thomas G. Thompson. Data was collected using a hull-mounted Kongsberg EM300 multibeam...

Date published: October 30, 2017

Hydrogen stable isotope data for: 'Mechanisms associated with an advance in the timing of seasonal reproduction in an urban songbird'

This dataset includes stable hydrogen isotope values of the nonexchangeable hydrogen contained in the outer most secondary feathers of dark-eyed juncos (Junco hyemalis thurberi) collected from the University of California San Diego campus in La Jolla, California in 2014.

Filter Total Items: 485
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Year Published: 2006

Subsurface structure of the East Bay Plain ground-water basin: San Francisco Bay to the Hayward fault, Alameda County, California

The area of California between the San Francisco Bay, San Pablo Bay, Santa Clara Valley, and the Diablo Ranges (East Bay Hills), commonly referred to as the 'East Bay', contains the East Bay Plain and Niles Cone ground-water basins. The area has a population of 1.46 million (2003 US Census), largely distributed among several cities, including...

Catchings, R. D.; Borchers, J.W.; Goldman, M. R.; Gandhok, G.; Ponce, D. A.; Steedman, C.E.
Subsurface structure of the East Bay Plain ground-water basin: San Francisco Bay to the Hayward fault, Alameda County, California; 2006; OFR; 2006-1084; Catchings, R. D.; Borchers, J. W.; Goldman, M. R.; Gandhok, G.; Ponce, D. A.; Steedman, C. E.

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Year Published: 2006

Seismic constraints and coulomb stress changes of a blind thrust fault system, 2: Northridge, California

We review seismicity, surface faulting, and Coulomb stress changes associated with the 1994 Northridge, California, earthquake. All of the observed surface faulting is shallow, extending meters to tens of meters below the surface. Relocated aftershocks reveal no seismicity shallower than 2 km depth. Although many of the aftershocks lie along the...

Stein, Ross S.; Lin, Jian
Seismic constraints and coulomb stress changes of a blind thrust fault system, 2: Northridge, California; 2006; OFR; 2006-1158; Stein, Ross S.; Lin, Jian

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Year Published: 2006

Seismic constraints and coulomb stress changes of a blind thrust fault system, 1: Coalinga and Kettleman hills, California

This report reviews the seismicity and surface ruptures associated with the 1982-1985 earthquake sequence in the Coalinga region in California, and the role of Coulomb stress in triggering the mainshock sequence and aftershocks. The 1982-1985 New Idria, Coalinga, and Kettleman Hills earthquakes struck on a series of west-dipping, en echelon blind...

Lin, Jian; Stein, Ross S.
Seismic constraints and coulomb stress changes of a blind thrust fault system, 1: Coalinga and Kettleman hills, California; 2006; OFR; 2006-1149; Lin, Jian; Stein, Ross S.

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Year Published: 2006

Digital database of recently active traces of the Hayward Fault, California

The purpose of this map is to show the location of and evidence for recent movement on active fault traces within the Hayward Fault Zone, California. The mapped traces represent the integration of the following three different types of data: (1) geomorphic expression, (2) creep (aseismic fault slip),and (3) trench exposures. This publication is...

Lienkaemper, James J.
Lienkaemper, J.J., 2006, Digital Database of Recently Active Traces of the Hayward Fault, California (ver. 1.1, November 2008): U.S Geological Survey Data Series 177, https://doi.org/10.3133/ds177.

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Year Published: 2006

Maps of quaternary deposits and liquefaction susceptibility in the Central San Francisco Bay Region, California

This report presents a map and database of Quaternary deposits and liquefaction susceptibility for the urban core of the San Francisco Bay region. It supercedes the equivalent area of U.S. Geological Survey Open-File Report 00-444 (Knudsen and others, 2000), which covers the larger 9-county San Francisco Bay region. The report consists of (1) a...

Witter, Robert C.; Knudsen, Keith L.; Sowers, Janet M.; Wentworth, Carl M.; Koehler, Richard D.; Randolph, Carolyn E.; Brooks, Suzanna K.; Gans, Kathleen D.
Maps of Quaternary Deposits and Liquefaction Susceptibility in the Central San Francisco Bay Region, California; 2006; OFR; 2006-1037; Witter, Robert C.; Knudsen, Keith L.; Sowers, Janet M.; Wentworth, Carl M.; Koehler, Richard D.; Randolph, Carolyn E.; Brooks, Suzanna K.; Gans, Kathleen D.

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Year Published: 2006

USGS science in Menlo Park -- a science strategy for the U.S. Geological Survey Menlo Park Science Center, 2005-2015

In the spring of 2004, the U.S. Geological Survey (USGS) Menlo Park Center Council commissioned an interdisciplinary working group to develop a forward-looking science strategy for the USGS Menlo Park Science Center in California (hereafter also referred to as "the Center"). The Center has been the flagship research center for the USGS in the...

Brocher, Thomas M.; Carr, Michael D.; Halsing, David L.; John, David A.; Langenheim, Victoria E.; Mangan, Margaret T.; Marvin-DiPasquale, Mark C.; Takekawa, John Y.; Tiedeman, Claire

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Year Published: 2006

Coastal landslide material loss rates associated with severe climatic events

Deep-seated landslides along the California coast deliver large amounts of material to the nearshore littoral environment. Landslide movement, a combined result of slope base undercutting by waves and ground saturation, is highly episodic. Movement occurs primarily during periods of high rainfall and large waves, such as those associated with El...

Hapke, C.J.; Green, K.R.
Coastal landslide material loss rates associated with severe climatic events; 2006; Article; Journal; Geology; Hapke, C. J.; Green, K. R.

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Year Published: 2006

Trophic structure and avian communities across a salinity gradient in evaporation ponds of the San Francisco Bay estuary

Commercial salt evaporation ponds comprise a large proportion of baylands adjacent to the San Francisco Bay, a highly urbanized estuary. In the past two centuries, more than 79% of the historic tidal wetlands in this estuary have been lost. Resource management agencies have acquired more than 10 000 ha of commercial salt ponds with plans to...

Takekawa, John Y.; Miles, A.K.; Schoellhamer, D.H.; Athearn, N.D.; Saiki, M.K.; Duffy, W.D.; Kleinschmidt, S.; Shellenbarger, G.G.; Jannusch, C.A.
Trophic structure and avian communities across a salinity gradient in evaporation ponds of the San Francisco Bay estuary; 2006; Conference Paper; Hydrobiologia; Takekawa, J. Y.; Miles, A. K.; Schoellhamer, D. H.; Athearn, N. D.; Saiki, M. K.; Duffy, W. D.; Kleinschmidt, S.; Shellenbarger, G. G.; Jannusch, C. A.

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Year Published: 2006

Trophic structure and avian communities across a salinity gradient in evaporation ponds of the San Francisco Bay estuary

Commercial salt evaporation ponds comprise a large proportion of baylands adjacent to the San Francisco Bay, a highly urbanized estuary. In the past two centuries, more than 79% of the historic tidal wetlands in this estuary have been lost. Resource management agencies have acquired more than 10 000 ha of commercial salt ponds with plans...

Takekawa, John Y.; Miles, A.K.; Schoellhamer, D.H.; Athearn, N.D.; Saiki, M. K.; Duffy, W.D.; Kleinschmidt, S.; Shellenbarger, G.G.; Jannusch, C.A.

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Year Published: 2005

Decadal-scale analysis of coastal landslides along the Big Sur coast: rates and processes

Hapke, Cheryl J.; Green, Krystal R.
Decadal-scale analysis of coastal landslides along the Big Sur coast: rates and processes; 2005; OFR; 2005-1434; Hapke, Cheryl J.; Green, Krystal R.

Filter Total Items: 1,119
Photo of a laboratory with various equipment and tables to work on.
December 31, 2017

PCMSC Marine Minerals Laboratory

A look into the USGS Pacific Coastal and Marine Science Center’s Marine Minerals Laboratory Suite.

man in yellow shirt and camo coveralls standing in thigh-high water with instrument.
December 31, 2017

Measuring streamflow in the Sisquoc River near Garey, California.

USGS technician measuring streamflow in the Sisquoc River near Garey, California, upstream of the Santa Maria Mesa Road Bridge.

scientific instruments and platform next to river surrounded by snow
December 31, 2017

USGS Streamgaging on the Pit River operates year round.

 USGS Streamgaging equipment and cableway on the Pit River near Canby, California operates year round.

USGS scientist collecting samples of aquatic species from the Pike River, Wis., for later analysis of mercury contamination.
December 31, 2017

Collecting samples of aquatic species from the Pike River, Wisconsin

Microbial Biogeochemistry Laboratory — Menlo Park, California. USGS scientist collecting samples of aquatic species from the Pike River, Wis., for later analysis of mercury contamination.

Two technicians in a cablecar over a river, with an instrument hanging below them
December 31, 2017

Lowering an acoustic Doppler current profiler from a cable way.

USGS technicians preparing for a streamflow measurement by lowering an acoustic Doppler current profiler from a cable way on the American River near Fair Oaks, California. 

two men in camo-patterned overalls standing next to a boat on the shore of a river with an instrument on the ground.
December 31, 2017

Technicians prepare to board a boat to measure water flow.

USGS technicians prepare to board a boat to go out to the center of the channel in the San Joaquin River below Friant Dam to get an accurate measurement of water flow during releases from the Dam for flood control.

 model grid with four rows and four columns showing A, types of cascading hydrologic response units (HRUs) and B, land-surface a
December 31, 2017

Model Grids with Cascading Hydrologic Response Units

Hypothetical model grid showing A, types of cascading hydrologic response units and B, land-surface altitudes and cascading flow directions.

man in yellow slicker standing in rushing river up to his thighs, holding a stick-like instrument in the water
December 31, 2017

Measuring streamflow in fast moving floodwater.

USGS hydrographer measuring streamflow using a handheld Acoustic Doppler Velocimeter in fast moving floodwater Cajon Creek near Keenbrook, California. 

Map shows a coastal city with an airport and how, during a large storm, ocean water would flood around city features.
December 31, 2017

CoSMoS projection for San Diego

Example of CoSMoS projected flooding extents for a 1.5 meter sea level rise in combination with possible 100 year return period coastal storms.

USGS
December 31, 2017

Big Brown Bat (Eptesicus fuscus) Call

Bats produce a variety of vocalizations that are used for navigation, feeding, and social communication. Most vocalizations are pitched well above the range of human hearing and are referred to as ultrasonic. These calls are often known as echolocation calls since bats use the echoes produced when a sound bounces off a bug or a building to determine what is in the area. 

Map of Active Faults and Historic Earthquakes in California
December 31, 2017

California Seismicity

Map of historic seismicity, major faults, and paleoseismic summary of San Andreas Fault system.

Filter Total Items: 991
USGS
December 13, 2013

Drought conditions are linked to declines in a protected desert tortoise population in part of the Sonoran Desert, according to a U.S. Geological Survey study. 

USGS
December 6, 2013

The U.S. Geological Survey participates in the American Geophysical Union's fall meeting with hundreds of technical presentations.  Below are some highlights of USGS science at AGU this year. Highlights about the technical sessions are presented in chronological order with session numbers, and room numbers in San Francisco's Moscone Convention Center...

USGS
November 18, 2013

Extensive groundwater pumping from San Joaquin Valley aquifers is increasing the rate of land subsidence, or sinking, that could result in serious operational and structural challenges and repairs to water infrastructure, according to a new report by the U.S. Geological Survey.

USGS
November 7, 2013

Although dousing the flames was foremost in people's minds during the recent Rim Fire in Stanislaus National Forest and Yosemite National Park, U.S. Geological Survey scientific work continues well after the fire is out. USGS scientists are continuing their critical research characterizing the hidden dangers faced after large wildfires.

USGS
November 4, 2013

A new cooperative study by the U.S. Geological Survey and the Hi-Desert Water District indicates that the artificial replenishment of the groundwater aquifer system in the west hydrogeologic unit of the Warren groundwater basin in San Bernardino County’s Yucca Valley resulted in a decrease of nitrate concentrations in groundwater samples and a rise in water levels.

Volcanic eruptions have a much longer warning phase before the onse...
October 29, 2013

On October 6, 2013 the California Office of Emergency Services (CalOES) published its 2013 State of California Multi-Hazard Mitigation Plan complete with a chapter from the USGS on volcano hazard mitigation.

Magnitude 3.8 earthquake (large purple dot) located about 18 km SE ...
October 21, 2013

A magnitude 3.8 earthquake occurred on October 21, 2013 at 10:04 PDT 18 km (11 miles) SE of the town of Mammoth Lakes in eastern California.

USGS
September 26, 2013

Nitrate was detected at high concentrations in 10 percent of the aquifer system used for public supply in coastal areas of Santa Barbara and San Luis Obispo counties, according to a new U.S. Geological Survey report.

USGS
September 12, 2013

California’s Sea Otter Numbers Continue Slow Climb

Tsunami Messaging Image
September 5, 2013

The fearsome aftermath of a tsunami striking California might cost at least $3.4 billion to repair, but neither of the state's nuclear power plants would be damaged, suggests a new analysis that could help officials and the public prepare for a tsunami and reduce risks before any such disasters happen.

USGS
September 4, 2013

While scientists can't predict when a great earthquake producing a pan-Pacific tsunami will occur, thanks to new tools being developed by federal and state officials, scientists can now offer more accurate insight into the likely impacts when tsunamis occur. This knowledge can lead officials and the public to reduce the risk of the future tsunamis that will impact California.

USGS
August 20, 2013

A new interagency report provides a plan for long-term scientific monitoring and assessment for California's Salton Sea. Monitoring of the Salton Sea ecosystem is critical for informed decision making and the success of restoration efforts.