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.
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Western Basin & Range - Eastern California Shear Zone
The Eastern California Shear Zone (ECSZ) Mapping project, funded by the National Cooperative Geologic Mapping Program, combines surficial and bedrock geologic mapping, geophysical surveys, and high-resolution topographic data analysis with neotectonic, geomorphic, structural, volcanic, and geochronologic studies to better understand the tectonic framework and landscape...
Comparing Shaking Intensity from Two Bay Area Earthquakes
The 1989 Loma Prieta earthquake caused billions of dollars in damage and claimed more than sixty lives. But was it "the big one"? Take a look at the comparison between the images below for the 1989 Loma Prieta and the 1906 San Francisco earthquakes, and decide for yourself.
The colors on the map indicate Modified Mercalli Shaking Intensity (MMI) at each point, which is usually (but not...
Paleoseismology and the Hayward Fault
A large, widely damaging earthquake will occur on the Hayward fault in the future. That much we know.
What we don't know is when.
Information by Region- California
Aerial Seabird and Marine Mammal Surveys
The Seabird Studies Team at the USGS Western Ecological Research Center is conducting aerial photographic surveys of the ocean off central and southern California to create comprehensive maps of seabird and marine mammal distributions. The project is supported by the Bureau of Ocean Energy Management and will inform planning in advance of potential offshore wind energy development along the...
The Coastal Storm Modeling System
The Coastal Storm Modeling System (CoSMoS) provides emergency responders and coastal planners with critical storm-hazard information such as flood extent, flood depth, duration of flooding, wave height, and currents that can be used to increase public safety, mitigate physical damages, and more effectively manage complex coastal settings....
Ecosystem Restoration in San Francisco Bay and Delta
In many systems, particularly the relatively dry western United States, freshwater that historically flowed into estuaries has been diverted for drinking water, agriculture, and industry. The resulting changes to water flow profoundly altered estuarine ecosystems. CMHRP studies in this complex system...
Salton Seismic Imaging
Studying Earthquake Hazards and Rifting Processes in the Imperial and Coachella Valleys
San Francisco Bay Area Arrays and the East Bay Seismic Experiment
Portable Seismograph Deployments to Research the Effects of Basins, Topography, and Fault Zones on Seismic Waves.
The implosion of the Warren Hall building on California State University East Bay (CSU-EB) campus in August of 2013 provided an excellent opportunity to use a “free” seismic source that was practically located on the Hayward Fault.
Improving Forecasting for California's Snow Melt Water Supply
California's Sierra Nevada snowpack accounts for much of the water supply in many parts of the state. The snowpack retains large amounts of water in the winter that is then released as temperatures rise in the spring and summer. The snowpack also keeps the Sierra soil moist by covering it longer into spring and summer. Soil moisture influences the onset of wildfires, as well as wildfire...
Basin Characterization Model - Simulating Effects of Iowa Soil Management on Water Availability
As a result of climate change, heavy rainfall, as well as extended dry periods, are becoming more common in the Midwestern United States. These trends are only expected to continue. So, increasing the capacity of soil to store water has become more critical. Storing water increases availability in dry conditions. And the absorption of additional water in wet conditions reduces potential...
Land Subsidence in California
Extensive groundwater withdrawals from aquifer systems have caused land subsidence in many California basins. Land subsidence can cause infrastructure damage, not only to buildings and roads but also to water conveyence systems. Groundwater-level and land-subsidence monitoring provide the information needed to guide mitigation efforts and management of future effects.
Groundwater quality data from Bristol and Cadiz Basins, San Bernardino County, California, USA
Water chemistry data from wells sampled by Standard Lithium Ltd. in Bristol and Cadiz Basins in San Bernardino County, California, USA
Historical produced water chemistry data compiled for the Orcutt and Oxnard oil fields, Santa Barbara and Ventura Counties, southern California
This digital dataset represents historical geochemical and other information for 58 sample results of produced water from 56 sites in the Orcutt and Oxnard oil fields in Santa Barbara and Ventura Counties, respectively, in southern California. Produced water is a term used in the oil industry to describe water that is produced as a byproduct along with the oil and gas. The locations from whic...
Success Dam spillway seismic refraction survey, Porterville, California, December 2018 and July 2019
Compressional- (P-) wave seismic refraction data were acquired in December 2018 and July 2019 along fourteen profiles within the spillway of Success Dam in Porterville, California. A new concrete ogee weir is planned for construction within the existing spillway, and the P-wave seismic velocity models will be used to inform further geotechnical investigations, including siting new geolo
Global Positioning System Survey data from 2015, Coachella Valley, Riverside County, California
Data collection: GPS measurements were taken at 24 geodetic monuments during September 27-October 2, 2015. The GPS surveys generally followed established guidelines (Zilkoski and others, 1997), except that the data were processed with single-baseline, rather than multi-baseline, software. GPS measurements were recorded at the monuments on at least 2 different days during 1-hour ob
Interferometric Synthetic Aperture Radar Data for 1995-2017
The data set consists of twenty-four individual interferograms and two stacked interferograms. Of the twenty-four individual interferograms, two interferograms were processed from synthetic aperture radar data acquired by the German Aerospace Center’s (DLR) TerraSAR-X satellite and twenty-two interferograms were processed from synthetic aperture radar data acquired by the European S
Physical and Biological Drivers of Fish Populations in the Sacramento Deep Water Shipping Channel, California, 2016-2018
This dataset includes field and lab data for fish, vegetation, zooplankton, phytoplankton, fish diets, and stable isotopes collected during daylight hours in the Sacramento Deep Water Shipping Channel in the Northern Sacramento-San Joaquin Delta, California, USA. This data release includes all measured environmental parameters, animal taxa, and isotope values included in the ana
Archive of boomer subbottom data collected offshore Eureka, California during USGS field activity W-1-96-NC from 1996-06-29 to 1996-07-07
This data release contains boomer subbottom data collected in June and July of 1996 on the shelf and slope offshore Eureka, California. Subbottom acoustic penetration spans up to several tens of meters, and is variable by location. This data release contains digital SEG-Y data. The data were collected aboard the R/V Wecoma using a Huntec Hydrosonde Deep-Tow system.
Airborne electromagnetic and magnetic survey, southwestern San Joaquin Valley near Lost Hills, California, 2016
Airborne electromagnetic (AEM) and magnetic survey data were collected during October 2016 along 1,443 line kilometers in the southwestern San Joaquin Valley near Lost Hills, California. These data were collected in support of groundwater salinity mapping and hydrogeologic framework development as part of the U.S. Geological Survey California Oil, Gas, and Groundwater program and the
Supporting groundwater salinity data used for salinity mapping adjacent to the Lost Hills and Belridge oil fields, Kern County, California
This dataset contains summarized historical groundwater salinity observations from wells near the Lost Hills and Belridge oil fields in the southwestern San Joaquin Valley, Kern County, California. Total dissolved solids (TDS) concentration, electrical fluid conductivity (EC), and well construction information were aggregated from public data sources and local water management age
Bathymetry, topography, and acoustic backscatter data, and a digital elevation model (DEM) of the Cache Slough Complex and Sacramento River Deep Water Ship Channel, Sacramento-San Joaquin Delta, California
This data release presents bathymetric and topographic data from surveys performed between 2017 and 2018 in the Cache Slough Complex and the Sacramento River Deep Water Ship Channel (DWSC), northern Sacramento-San Joaquin Delta, California. The shallow, highly vegetated aquatic habitats of this region necessitated a variety of survey platforms and techniques. In the deeper channels, swath...
Bathymetry, topography, and acoustic backscatter data, and a digital elevation model of the Cache Slough Complex and Sacramento River Deep Water Ship Channel, Sacramento-San Joaquin Delta, California
This data release presents bathymetric and topographic data from surveys performed between 2017 and 2018 in the Cache Slough Complex and the Sacramento River Deep Water Ship Channel (DWSC), northern Sacramento-San Joaquin Delta, California. The shallow, highly vegetated aquatic habitats of this region necessitated a variety of survey platforms and techniques. In the deeper channels, swath...
Digital elevation model (DEM) of the Sacramento River Deep Water Ship Channel (DWSC), Sacramento-San Joaquin Delta, California
This metadata describes a digital elevation model (DEM) created from bathymetric and topographic data collected between 2017 and 2019 in the Sacramento River Deep Water Ship Channel (DWSC), northern Sacramento-San Joaquin Delta, California.
We merged the newly collected bathymetric and topographic data presented in this data release (DOI:10.5066/P9AQSRVH) with 2019 surveys b
A spatiotemporal clustering model for the Third Uniform California Earthquake Rupture Forecast (UCERF3‐ETAS): Toward an operational earthquake forecast
We, the ongoing Working Group on California Earthquake Probabilities, present a spatiotemporal clustering model for the Third Uniform California Earthquake Rupture Forecast (UCERF3), with the goal being to represent aftershocks, induced seismicity, and otherwise triggered events as a potential basis for operational earthquake forecasting (OEF)....
Field, Edward H.; Milner, Kevin R.; Hardebeck, Jeanne L.; Page, Morgan T.; van der Elst, Nicholas; Jordan, Thomas H.; Michael, Andrew J.; Shaw, Bruce E.; Werner, Maximillan J. Trace element contamination in feather and tissue samples from Anna’s hummingbirds
Trace element contamination (17 elements; Be, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Cd, Ba, Hg, Tl, and Pb) of live (feather samples only) and deceased (feather and tissue samples) Anna's hummingbirds (Calypte anna) was evaluated. Samples were analyzed using inductively coupled plasma-mass spectrometry (ICP-MS; 17 elements) and atomic...
Mikoni, Nicole A.; Poppenga, Robert H.; Ackerman, Joshua T.; Foley, Janet E.; Hazlehurst, Jenny; Purdin, Güthrum; Aston, Linda; Hargrave, Sabine; Jelks, Karen; Tell, Lisa A. A paleoseismic transect across the northwestern Basin and Range Province, northwestern Nevada and northeastern California, USA
We use new and existing data to compile a record of ∼18 latest Quaternary large-magnitude surface-rupturing earthquakes on 7 fault zones in the northwestern Basin and Range Province of northwestern Nevada and northeastern California. The most recent earthquake on all faults postdates the ca. 18–15 ka last glacial highstand of pluvial Lake Lahontan...
Personius, Stephen; Briggs, Richard W.; Maharrey, J. Zebulon; Angster, Stephen J.; Mahan, Shannon A. Effect of hydraulic hysteresis on the stability of infinite slopes under steady infiltration
Hydraulic hysteresis, including capillary soil water retention (SWR), air entrapment SWR, and hydraulic conductivity, is a common phenomenon in unsaturated soils. However, the influence of hydraulic hysteresis on suction stress, and subsequently slope stability, is generally ignored. This paper examines the influence of each of these three types...
Chen, Pan; Mirus, Benjamin B.; Lu, Ning; Godt, Jonathan W. The California Seafloor and Coastal Mapping Program – Providing science and geospatial data for California's State Waters
The California Seafloor and Coastal Mapping Program (CSCMP) is a collaborative effort to develop comprehensive bathymetric, geologic, and habitat maps and data for California's State Waters. CSCMP began in 2007 when the California Ocean Protection Council (OPC) and the National Oceanic and Atmospheric Administration (NOAA) allocated funding for...
Johnson, Samuel Y.; Cochrane, Guy R.; Golden, Nadine; Dartnell, Peter; Hartwell, Stephen; Cochran, Susan A.; Watt, Janet Accelerating slip rates on the puente hills blind thrust fault system beneath metropolitan Los Angeles, California, USA
Slip rates represent the average displacement across a fault over time and are essential to estimating earthquake recurrence for proba-bilistic seismic hazard assessments. We demonstrate that the slip rate on the western segment of the Puente Hills blind thrust fault system, which is beneath downtown Los Angeles, California (USA), has accel-erated...
Bergen, Kristian J.; Shaw, John H.; Leon, Lorraine A.; Dolan, James F.; Pratt, Thomas L.; Ponti, Daniel J.; Morrow, Eric; Barrera, Wendy; Rhodes, Edward J.; Murari, Madhav K.; Owen, Lewis A. Adapting California’s ecosystems to a changing climate
Significant efforts are underway to translate improved understanding of how climate change is altering ecosystems into practical actions for sustaining ecosystem functions and benefits. We explore this transition in California, where adaptation and mitigation are advancing relatively rapidly, through four case studies that span large spatial...
Elizabeth Chornesky; David Ackerly; Paul Beier; Davis, Frank W.; Flint, Lorraine E.; Lawler, Joshua J.; Moyle, Peter B.; Moritz, Max A.; Scoonover, Mary ; Byrd, Kristin B.; Alvarez, Pelayo; Heller, Nicole E.; Micheli, Elisabeth; Weiss, Stuart CoSMoS (Coastal Storm Modeling System) Southern California v3.0 Phase 2 storm-hazard projections
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 (...
Barnard, Patrick; Erikson, Li; O'Neill, Andrea; Foxgrover, Amy; Herdman, Liv Ground motion in the presence of complex Topography II: Earthquake sources and 3D simulations
Eight seismic stations were placed in a linear array with a topographic relief of 222 m over Mission Peak in the east San Francisco Bay region for a period of one year to study topographic effects. Seventy‐two well‐recorded local earthquakes are used to calculate spectral amplitude ratios relative to a reference site. A well‐defined...
Hartzell, Stephen H.; Ramirez-Guzman, Leonardo; Meremonte, Mark; Leeds, Alena L. Records of continental slope sediment flow morphodynamic responses to gradient and active faulting from integrated AUV and ROV data, offshore Palos Verdes, southern California Borderland
Variations in seabed gradient are widely acknowledged to influence deep-water deposition, but are often difficult to measure in sufficient detail from both modern and ancient examples. On the continental slope offshore Los Angeles, California, autonomous underwater vehicle, remotely operated vehicle, and shipboard methods were used to collect a...
Maier, Katherine L.; Brothers, Daniel; Paull, Charles K.; McGann, Mary; Caress, David W.; Conrad, James E. Status of White Sturgeon (Acipenser transmontanus Richardson, 1863) throughout the species range, threats to survival, and prognosis for the future
White Sturgeon, Acipenser transmontanus (WS), are distributed throughout three major river basins on the West Coast of North America: the Sacramento-San Joaquin, Columbia, and Fraser River drainages. Considered the largest North American freshwater fish, some WS use estuarine habitat and make limited marine movements between river basins...
Hildebrand, L. R.; Drauch Schreier, Andrea; Lepla, K.; McAdam, S. O.; McLellan, J; Parsley, Michael J.; Paragamian, V L; Young, S P
High-resolution seismic-reflection data from offshore northern California — Bolinas to Sea Ranch
The U.S. Geological Survey collected high-resolution seismic-reflection data in September 2009, on survey S-8-09-NC, offshore of northern California between Bolinas and Sea Ranch.The survey area spans about 125 km of California’s coast and extends around Point Reyes. Data were collected aboard the U.S. Geological Survey R/V Parke Snavely....
Sliter, Ray W.; Johnson, Samuel Y.; Chin, John L.; Allwardt, Parker; Beeson, Jeffrey; Triezenberg, Peter J.
TOC-L Laboratory Total Organic Carbon Analyzer
TOC-L Laboratory Total Organic Carbon Analyzer
Labconco WaterPros PS ultrapure water filtration system in Biology Lab
Labconco WaterPros PS ultrapure water filtration system in Biology Lab
Fume Hood in Carbon Lab used for acid storage and acid cleaning of lab
Fume Hood in Carbon Lab used for acid storage and acid cleaning of laboratory dishware
Fume Hood in Carbon Lab
Horiba Aqaulog - simultaneously measures absorbance spectra and fluorescence Excitation-Emission Matrices
PubTalk 08/2019 — Pliocene World
Title: Pliocene World: Earth's Climate 3 Million Years Ago and How it Relates to our Future
By Marci Robinson, USGS Research Geologist
- Three million years ago, during the late Pliocene, CO2 levels were similar to today, but global temperatures and sea level were much higher
- Find out how we use microfossils to reconstruct
Scott Lydeen on Strawberry Peak Seismic Station Tower
USGS technicial Scott Lydeen climbing the tower at the Strawberry Peak seismic station tower, part of the Southern California Seismic Network.
Animation of a Scenario M6.9 Earthquake on the Rose Canyon Fault
This video presents an animation of computer-simulated ground motions that might occur for a magnitude 6.9 earthquake rupturing the Rose Canyon fault in southern California. The scenario earthquake ruptures a 65-km-long section of the Rose Canyon fault that lies just offshore of San Diego, California, and Tijuana, Mexico. In this scenario, the rupture starts near the
Image of the Week - A Tear in the Mojave
Satellite imagery shows the rupture and shifting of land near Ridgecrest, CA from the July 2019 earthquakes.
Researchers from the USGS Pacific Coastal and Marine Science Center (PCMSC) participated in a research cruise to survey deep-water coral, sponge, and fish habitats off U.S. West Coast.
A low-flying helicopter under contract to the U.S. Geological Survey, in cooperation with the California State Water Resources Control Board, has begun collecting and recording geophysical measurements for purpose of groundwater salinity and aquifer mapping.
Turbidity currents have historically been described as fast-moving currents that sweep down submarine canyons, carrying sand and mud into the deep sea. But a new paper in Nature Communications shows that, rather than just consisting of sediment-laden seawater flowing over the seafloor, turbidity currents also involve large-scale movements of the seafloor itself.
From October 9–15, USGS personnel surveyed beaches and the adjacent ocean floor along Monterey Bay’s northern coast.
On October 17, 2018, 17 staff members from the City of Santa Cruz, California toured USGS facilities in the city.
By Thomas M. Brocher, Jack Boatwright, James J. Lienkaemper, Carol S. Prentice, David P. Schwartz, and Howard Bundock
Drawn from: USGS Fact Sheet 2018-3052
Large underwater experiment in California’s Monterey Canyon shows that “turbidity currents” are not just currents, but involve movement of the seafloor itself.
On September 18, Congressman Jimmy Panetta (20th district, California) and staffer Emmanuel Garcia visited the USGS Pacific Coastal and Marine Science Center in Santa Cruz.
Did you know that the USGS is studying raptors in California? Biologists with the USGS Western Ecological Research Center are hard at work in the field, learning more about the ecology of Northern Harriers and their interactions with migratory waterfowl of concern to the U.S. Fish and Wildlife Service.
From July 31 to August 23, a joint USGS-NOAA cruise mapped seafloor depths, texture, and gas seeps in the Cascadia subduction zone offshore of Washington, Oregon, and northern California.
USGS and NASA researchers met July 16 at NASA’s Jet Propulsion Laboratory (JPL) to discuss Synthetic Aperture Radar (SAR) imagery of the Southern California coast collected during higher-than-normal tides (“king tides”) in fall 2016.
New report on how the bend in an offshore fault helps shape the Big Sur coast
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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
Fort Collins Science Center
Phone: 970-226-9100
Fax: 970-226-9230
USGS California Volcano Observatory (CalVO package delivery)
askcalvo@usgs.gov
Phone: 650-329-5083
Poway Field Office (USGS California Water Science Center)
Phone: 858-679-4015
Fax: 858-679-4019
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
USGS Menlo Park Library
men_lib@usgs.gov
Phone: 650-329-5027
Fax: 650-329-5132