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
Population Biology and Behavior of Sea Otters
WERC's sea otter researchers are developing and utilizing a variety of methodological and analytical tools to understand the causes of biological and ecological trends in sea otter populations, and to predict the ecological consequences of management practices on these populations and their ecosystems.
Waterfowl Ecology in California and the Pacific Flyway
The Suisun Marsh and Central Valley in California offer some of the world’s most important wetland habitats for waterfowl in the Pacific Flyway. Mike Casazza and USGS WERC biologists are providing the science to support and evaluate waterfowl populations and habitat management in North America.
Pacific Nearshore Project
Sea otters are crucial indicators of the health of our nearshore waters and coastal resources, from kelp forests to fisheries. What clues does the sea otter's decline hold for our knowledge of ecosystem and global change? WERC's sea otter team and U.S. and Canadian researchers have teamed together to investigate.
Relevance to USGS Missions:
This research project has direct...
Modeling Sea-Level Rise in San Francisco Bay Estuary
With sea level rise, how will the coastal habitats of the San Francisco Bay Estuary change over the next 100 years? Mapping and modeling studies by Dr. Karen Thorne, WERC scientists, and partners have produced scenarios for this important coastal ecosystem.
Ecology and Population Dynamics of Ridgway's Rails along the West Coast of the U.S.
The Ridgway’s rail is a federal and state listed endangered species that occurs in wetlands along the Pacific Coast and from the Lower Colorado River drainage to southern Baja California. Three subspecies of Ridgway’s rail are found within the United States: the California Ridgway’s Rail, Yuma Ridgway’s rail, and Light-footed Ridgway’s rail. All three subspecies have declined since 1900 as a...
Wildland Fire Science in Forests and Deserts
Fuel conditions and fire regimes in western forests and deserts have been altered due to past land management, biological invasions, and recent extreme weather events and climate shifts. These changes have created extreme fire risk to local and regional communities, threatening their economic health related to wildland recreation, forest production, livestock operations, and other uses of...
Aridlands Disturbances and Restoration Ecology
Desert landscapes are rapidly changing due to increases in invasive plant species, frequency of wildfires, urban and energy development, recreational use, military training, and climate variation. Dr. Todd Esque, USGS researchers, and collaborators are working together to investigate these changes and provide managers with key information that can be used to manage natural resources more...
Coastal Ecosystem Response to Sea-level Rise
USGS WERC’s Dr. Karen Thorne, her team of reseachers, and her partners are currently taking a local site network approach to describe current and future conditions and projected responses of coastal ecosystems to sea-level rise and other stressors. The Coastal Ecosystem Response to Climate Change (CERCC) program’s goal is to understand how ecosystems vary in their ability to keep up with sea-...
Desert Tortoise Ecology, Health, Habitat, and Conservation Biology
The desert tortoise is listed as “threatened” under the Endangered Species Act. USGS WERC scientists, along with project partners have been conducting long-term analyses on how changes in the southwestern deserts of the United States can affect desert tortoise populations. Dr. Todd Esque and his team are investigating how habitat disturbances and restoration projects influence tortoise...
Breeding and Wintering Ecology of Waterfowl
Western U.S. wetlands provide critical habitat for wintering and breeding waterfowl in California. WERC's Dr. Josh Ackerman is working toward collecting data to understand factors influencing duck nest success, to improve and restore breeding habitat for resident duck populations in California, and understand composition of predator communities. To learn more about how USGS WERC is...
Land Treatment Digital Library
The LTDL was created by the U.S. Geological Survey (USGS) to catalog information about land treatments on Federal lands in the western United States for all interested parties. The flexible framework of the library allows for the storage of a wide variety of data in different formats. The LTDL currently stores previously established land treatments or what often are called legacy data. The...
RestoreNet: Distributed Field Trial Network for Dryland Restoration
U.S. Geological Survey (USGS) researchers and land managers are co-producing a network of restoration field trial sites on DOI and surrounding lands in the southwestern U.S. The network systematically tests restoration treatments across a broad range of landscape, soil, and climate conditions. Each site in the network is used to test suitable seed mixes and treatments that promote plant...
California Seafloor Mapping Program progress
Table showing California Seafloor Mapping Program map block mapping progress by block number, as of April 2018.
Beach topography and nearshore bathymetry of northern Monterey Bay, California
This data release presents beach topography and nearshore bathymetry data from repeated surveys in northern Monterey Bay, California to document changes in shoreline position and coastal morphology as they relate to episodic (storms), seasonal, and interannual and longer processes. Since October 2014, semi-annual surveys have been performed in late summer (September or October...
Grain size, mineralogic, and trace-element data from field samples near Hinkley, California
This data release is part of a study examining the occurrence of chromium and natural and anthropogenic hexavalent Chromium, Cr(VI) in groundwater. Data will be used to estimate naturally-occurring background Cr(VI) concentrations upgradient, near the plume margins, and downgradient from a mapped Cr(VI) contamination plume near Hinkley, CA (Izbicki and Groover, 2016).
Bathymetry, acoustic-backscatter, and time-series datasets collected between 2014 and 2016 of a field of crescent-shaped rippled scour depressions in northern Monterey Bay, California
Between 11/14-6/16 USGS PCMSC conducted 8 repeat, high-resolution bathymetry and acoustic-backscatter surveys of a small patch of seafloor offshore Santa Cruz in northern Monterey Bay, California. We also collected oceanographic time-series data over the same two-year period. This data release provides the eight bathymetry and acoustic-backscatter datasets, the time-series data, and FGDC...
Electrical Resistivity Tomography Data at Fort Irwin National Training Center, San Bernardino County, California, 2015 and 2017
The U.S. Army Fort Irwin National Training Center (NTC), approximately 35 mi north-northeast of Barstow, California, covers approximately 1,177 square miles, and is comprised of ten groundwater basins, three of which have been subdivided into subbasins on the basis of additional hydrologic testing. Since the early 1990s, the U.S. Geological Survey (USGS) has been studying water resources...
Bathymetry and acoustic backscatter data collected in 2007 from the San Miguel Passage in the Channel Islands, California
Bathymetry and acoustic backscatter data were collected in the San Miguel Passage, Channel Islands, California in August 2007. Data collection was conducted aboard the ship R/V Shearwater as part of the USGS research cruise S-2-07-SC. The San Miguel Passage is within the Channel Islands National Marine Sanctuary, and is the body of water between the two western-most islands of the...
USGS Domestic Continuous (Unconventional) Oil & Gas Assessments, 2000-Present
Interactively explore assessment summary information for continuous (unconventional) assessments conducted at the USGS from 2000-2018. The assessment results data used to generate this visualization can be downloaded here in Excel Format. These data represent all assessment results...
GAMA-Priority Basin Project Groundwater-Quality Results: Assessment and Trends
This interactive webmap plots water-quality data from domestic and public-supply wells sampled by the USGS for the California Groundwater Ambient Monitoring and Assessment Program (GAMA) Priority Basin Project, and allows users to download datasets.
In situ geochemical data related to the gold-quartz veins of Grass Valley, California, 2014-2015
In situ geochemical data were obtained for pyrite crystals and native gold from two distinct vein sets in the Grass Valley gold district, California. Samples of the N-S (north-south-trending) veins were collected underground at the Empire Mine State Historic Park and samples of the E-W (east-west-trending) veins were collected from drill core provided by the Idaho-Maryland Mining Corpor
Water Use Data for California
State water-use data are reported by source (surface water or groundwater, fresh and saline, and total), category, and area type (county). The water-use data presented here are the current best estimates, and may have been revised from previous publications. Data collection varied between the different compilations. Pre-1995 datasets have more data available than 2000 and later.
Groundwater-quality data and ancillary data for selected wells in the San Joaquin Valley, California, 1900-2015
This report provides a full digitization of historic groundwater-quality and depth-to-water data from Mendenhall and others (1916) Water Supply Paper 398, “Ground Water in San Joaquin Valley, California” in a modern format suitable for further analysis of California’s water supply resources. Included are geochemical data for over 400 wells collected by Mendenhall i
Historic Depth-to-Water, San Joaquin Valley, California, 1910
Mendenhall and others (1916) published depth-to-water data compiled in 1910 for all known wells in the San Joaquin Valley, California. Data for the 3,429 wells having depth-to-water of greater than zero feet were used to construct an interpolated depth-to-water surface for the entire SJV. This map represents groundwater levels in approximately 1910, prior to extensive development of the
Year 3 Summary Report: Baseline Selenium Monitoring of Agricultural Drains Operated by the Imperial Irrigation District in the Salton Sea Basin
This report summarizes findings from the third year of a 4-year-long field investigation to document selected baseline environmental conditions in 29 agricultural drains and ponds operated by the Imperial Irrigation District along the southern border of the Salton Sea. Routine water quality and fish species were measured at roughly quarterly...
Saiki, Michael K.; Martin, Barbara A.; May, Thomas W. Liquefaction hazard maps for three earthquake scenarios for the communities of San Jose, Campbell, Cupertino, Los Altos, Los Gatos, Milpitas, Mountain View, Palo Alto, Santa Clara, Saratoga, and Sunnyvale, Northern Santa Clara County, California
Maps showing the probability of surface manifestations of liquefaction in the northern Santa Clara Valley were prepared with liquefaction probability curves. The area includes the communities of San Jose, Campbell, Cupertino, Los Altos, Los Gatos Milpitas, Mountain View, Palo Alto, Santa Clara, Saratoga, and Sunnyvale. The probability curves were...
Holzer, Thomas L.; Noce, Thomas E.; Bennett, Michael J. Historical seismicity in the South San Francisco Bay Region
Locations (intensity centers) and moment magnitude M for 24 earthquakes (1858-1911) in the southern San Francisco Bay area are estimated from Modified Mercalli intensity (MMI) assignments. The uncertainties in location and M are generally large because there are few MMI assignments available. Preferred locations are selected to be consistent with...
Bakun, William H. Structure of the San Bernardino Basin along two seismic transects: Rialto-Colton Fault to the San Andreas Fault and along the I-215 Freeway (I-10 to SR30)
In this report, we present seismic data and acquisition parameters for two seismic profiles acquired in the San Bernardino, California area in May and October 2003. We refer to these seismic profiles as the San Bernardino Regional (SBR) and San Bernardino High-Resolution (SBHR) seismic profiles. We present both un-interpreted and interpreted...
Catchings, R.D.; Rymer, M.J.; Goldman, M.R.; Gandhok, G.; Steedman, C.E. Total selenium and selenium species in irrigation drain inflows to the Salton Sea, California, October 2007 and January 2008
This report presents the results for two sampling periods (October 2007 and January 2008) during a 4-year monitoring program to characterize selenium concentrations in selected irrigation drains flowing into the Salton Sea, California. Total selenium, selenium species (selenite, selenate, organoselenium), and total suspended solids were determined...
May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G. The ShakeOut Earthquake Scenario— A story that southern Californians are writing
The question is not if but when southern California will be hit by a major earthquake - one so damaging that it will permanently change lives and livelihoods in the region. How severe the changes will be depends on the actions that individuals, schools, businesses, organizations, communities, and governments take to get ready. To help prepare for...
Perry, Suzanne; Cox, Dale; Jones, Lucile; Bernknopf, Richard; Goltz, James; Hudnut, Kenneth; Mileti, Dennis; Ponti, Daniel; Porter, Keith; Reichle, Michael; Seligson, Hope; Shoaf, Kimberley; Treiman, Jerry; Wein, Anne The ShakeOut Scenario
This is the initial publication of the results of a cooperative project to examine the implications of a major earthquake in southern California. The study comprised eight counties: Imperial, Kern, Los Angeles, Orange, Riverside, San Bernardino, San Diego, and Ventura. Its results will be used as the basis of an emergency response and preparedness...
Jones, Lucile M.; Bernknopf, Richard; Cox, Dale; Goltz, James; Hudnut, Kenneth; Mileti, Dennis; Perry, Suzanne; Ponti, Daniel; Porter, Keith; Reichle, Michael; Seligson, Hope; Shoaf, Kimberley; Treiman, Jerry; Wein, Anne Leachate Geochemical Results for Ash and Burned Soil Samples from the October 2007 Southern California Wildfires
This report is the second release of leachate geochemical data included as part of a multidisciplinary study of ash and burned soil samples from the October 2007 wildfires in southern California. Geochemical data for the first set of samples were released in an Open-File Report (Plumlee and others, 2007). This study is a continuation of that work...
Hageman, Philip L.; Plumlee, Geoffrey S.; Martin, Deborah A.; Hoefen, Todd M.; Meeker, Gregory P.; Adams, Monique; Lamothe, Paul J.; Anthony, Michael W. A-priori rupture models for Northern California Type-A faults
This appendix describes how a-priori rupture models were developed for the northern California Type-A faults. As described in the main body of this report, and in Appendix G, “a-priori” models represent an initial estimate of the rate of single and multi-segment surface ruptures on each fault. Whether or not a given model is moment balanced (i.e...
Wills, Chris J.; Weldon, Ray J.; Field, Edward H. Compilation of surface creep on California faults and comparison of WGCEP 2007 deformation model to Pacific-North American plate Mmtion
This Appendix contains 3 sections that 1) documents published observations of surface creep on California faults, 2) constructs line integrals across the WG-07 deformation model to compare to the Pacific - North America plate motion, and 3) constructs strain tensors of volumes across the WG-07 deformation model to compare to the Pacific - North...
Wisely, Beth A.; Schmidt, David A.; Weldon, Ray J. Conditional, time-dependent probabilities for segmented Type-A faults in the WGCEP UCERF 2
This appendix presents elastic-rebound-theory (ERT) motivated time-dependent probabilities, conditioned on the date of last earthquake, for the segmented type-A fault models of the 2007 Working Group on California Earthquake Probabilities (WGCEP). These probabilities are included as one option in the WGCEP?s Uniform California Earthquake Rupture...
Field, Edward H.; Gupta, Vipin Paleoseismic Investigations of the Walnut Site on the San Jacinto Fault
The Walnut paleoseismic site is located along the northern San Jacinto fault about 3 km southeast of the San Bernardino, California city center (Figures 1, 2). More than 340 meters of trenches were excavated across the fault zone at this site as part of an Alquist-Priolo fault study (Figure 3). We photographed and logged the SE wall and most of...
Fumal, T.E.; Kendrick, K.J.
Gas chromatograph-mass spectrometer (GCMS) used for pesticide analysis
Organic Chemistry Research Laboratory — Sacramento, California. Gas chromatograph-mass spectrometer - GCMS
Little Holland Tract and Liberty Island sample locations, 2014-2017
Sediment sampling locations in the Sacramento-San Joaquin Delta, California near Little Holland Tract and Liberty Island, 2014 to 2017
CoSMoS Implementation versions
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 SLR scenarios, as well as long-term shoreline change and cliff retreat. Resulting projections for future climate scenarios (sea-level rise and storms) provide
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Earthquake Alerts: Early and Often? Or Possibly Late?
The choice when issuing earthquake warnings is to: 1) issue alerts for weak shaking and potentially provide long warning times, but risk sending alerts for the many events that do not go on to produce damaging ground shaking, or 2) issue alerts only when ground shaking is expected to be damaging, with the tradeoff that the alert will be sent much later, reducing the
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Striped Bass diet sampling in the San Francisco Estuary
Sampling Striped Bass for diet items in the San Francisco Estuary.
Nearshore survey of San Ysidro Creek
Two USGS scientists operate personal watercraft equipped with sonar and GPS along the beachfront off San Ysidro Creek, near Fernald Point in Montecito, California. They will use the data collected to create bathymetric (depth) maps. Collecting these data on a seasonal basis over many years provides a detailed picture of how the coastline reacts to changes in waves and
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Instrument package for river data collection
Patches of dark sand cling to an instrument package that collected data for approximately two weeks at the Mokelumne River site—evidence that currents at the site were strong enough to carry sand, which is heavier than mud, probably during elevated river flows following two storms in the watershed.
Fieldwork in the Delta
Shruti Khanna (left, California Department of Fish and Wildlife) and Judy Drexler (USGS California Water Science Center) on the USGS Pacific Coastal and Marine Science Center’s research vessel Parke Snavely during fieldwork in the Sacramento-San Joaquin River Delta.
Gomex sediment corer preparation
Dan Powers (USGS PCMSC) and Rachel Marcuson (USGS PCMSC) prepare to deploy a Gomex sediment corer from the R/V Snavely in the Mokulumne River near confluence of San Joaquin River in the Sacramento-San Joaquin Delta, CA.
Deploying tripod in the Delta
USGS physical scientist Cordell Johnson, at left, and USGS research oceanographer Jessie Lacy, both from the Pacific Coastal and Marine Science Center, guide a tripod with instruments into the waters of the Mokelumne River near the confluence with the San Joaquin River. The Mokelumne is part of the vast Sacramento-San Joaquin River Delta in California, located east of San
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Mokelumne River survey
Mokelumne River near confluence with the San Joaquin River in the Sacramento-San Joaquin Delta, CA, looking downstream, with Cordell Johnson (USGS PCMSC) and Rachel Allen (USGS PCMSC) collecting data from the R/V Fast Eddy.
Mokelumne River survey
Mokelumne River near confluence with the San Joaquin River in the Sacramento-San Joaquin Delta, CA, looking downstream, with Cordell Johnson (USGS PCMSC) and Rachel Allen (USGS PCMSC) collecting data from the R/V Fast Eddy.
What can wildlife diseases tell us about the emergence of human pandemics?
During the week of Oct 20 - 24 scientists from the U.S. Geological Survey will be working along the coastline from Santa Cruz to Moss Landing. Either by all-terrain vehicle, personal watercraft, or on foot, they will be surveying local beaches and the nearby ocean bottom to compile a three-dimensional map of how beaches change in northern Monterey Bay.
The Downtown Association of Santa Cruz will host a 25th anniversary commemoration of the Loma Prieta Earthquake.
The USGS California Volcano Observatory (CalVO) is tracking an earthquake swarm in the Sierra Nevada range south of Long Valley Caldera, about 8 miles SW of Toms Place and 15 miles SE of the town of Mammoth Lakes.
Over the past 42 hours, the earthquake swarm in California's Long Valley Caldera, which began last Friday (see September 26 post), has gradually diminished in terms of numbers of earthquakes and in earthquake magnitude.
We have been closely tracking an earthquake swarm in California's Long Valley Caldera, which started yesterday at around 4AM PDT (September 25, 2014).
On the afternoon of September 20, a large volume of water surged down Mount Shasta's south flank into Mud Creek, entraining debris and inundating the drainage and roads near McCloud, California.
When sea otters want to rest, they wrap a piece of kelp around their body to hold themselves steady among the rolling waves. Likewise, California’s sea otter numbers are holding steady against the many forces pushing against their population recovery, according to the latest field survey led by federal, state, aquarium, and university scientists.
The U.S. Geological Survey will host an educational event for the news media focused on earthquakes on Wednesday September 24, 2014.
Scientists at the U.S. Geological Survey have developed a new mapping tool, the Pedestrian Evacuation Analyst, for use by researchers and emergency managers to estimate how long it would take for someone to travel on foot out of a tsunami-hazard zone.
Newly released US Topo maps for Oregon now feature segments of the Pacific Crest National Scenic Trail. Several of the 1,835 new US Topo quadrangles for the state now display parts of the Trail along with other improved data layers.
Naturally occurring trace elements were detected at high concentrations in less than 3 percent of raw groundwater sources used for public water supply in the Klamath Mountain area, according to the ongoing U.S. Geological Survey study of California groundwater quality.
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Locations
Southwest Regional Director's Office
Phone: (916) 278-9551
Fax: (916) 278-9566
Pacific Coastal and Marine Science Center
Phone: 831-460-7401
Fax: 831-427-4748
Sacramento Projects Office (USGS California Water Science Center)
Phone: 916-278-3000
Fax: 916-278-3070
Western Ecological Research Center - Headquarters
Phone: (916) 278-9485
Fax: (916) 278-9475
Geology, Minerals, Energy and Geophysics Science Center
Phone: (650) 329-4881
Earthquake Science Center
Western Geographic Science Center - Main Office
San Diego Projects Office (USGS California Water Science Center)
Phone: 619-225-6100
Fax: 619-225-6101
USGS California Volcano Observatory (CalVO package delivery)
askcalvo@usgs.gov
Phone: 650-329-5083
Truckee Field Office (USGS California Water Science Center)
Phone: 530-587-0910
Fax: 530-587-0914
Redding Field Office (USGS California Water Science Center)
Phone: 530-246-5282
Fax: 530-246-0717
Ukiah Field Office (USGS California Water Science Center)
Phone: 707-468-4040
Fax: 707-468-4022
Redlands Field Office (USGS California Water Science Center)
Phone: 909-798-3272
West Sacramento Projects Office (USGS California Water Science Center)
Phone: 916-617-2799
Eureka Satellite Office (USGS California Water Science Center)
Phone: 707-442-3169
Fax: 707-445-7860
Sacramento Field Office (USGS California Water Science Center)
Phone: 916-381-0207
Fax: 916-381-0556
Santa Cruz Field Office (USGS California Water Science Center)
Phone: 831-460-7494
Santa Maria Field Office (USGS California Water Science Center)
Phone: 805-928-9539
Fax: 805-928-9220
Poway Field Office (USGS California Water Science Center)
Phone: 858-679-4015
Fax: 858-679-4019
USGS Menlo Park Library
men_lib@usgs.gov
Phone: 650-329-5027
Fax: 650-329-5132