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
San Francisco Bay Area – SF Peninsula (BALT3) Site near Brisbane, CA
San Francisco Bay Area – Marin County (BALT2) Site near San Rafael, CA
Drivers and Impacts of North Pacific Climate Variability
Climate model forecasts indicate an increase in extreme hydrologic events, including floods and droughts, for California and the western U.S. in the future. To better understand what the consequences of this future change in climate may be, USGS scientists are studying the frequency, magnitude, and impacts of past hydroclimate variability and extremes in the region. This project produces well-...
What if the ShakeAlert Earthquake Early Warning System Had Been Operating During the M6.9 1989 Loma Prieta Earthquake?
How will ShakeAlert® likely perform now on a large earthquake impacting a major urban area? How much warning will you get? To answer this, let’s do a thought experiment...
CoSMoS 3.1: Central California
CoSMoS v3.1 for central California shows projections for future climate scenarios (sea-level rise and storms)
Topobathymetric Elevation Model of San Francisco Bay Area, California
Accurate, high-resolution elevation information is vital to understanding the natural hazards that can impact the highly populated San Francisco Bay area, such as sea-level rise, winter storms, cliff erosion, and other coastal hazards. The San Francisco Bay estuary three-dimensional (3D) topobathymetric digital elevation model (TBDEM) was developed in collaboration between ...
Earthquake Early Warning – Fine-Tuning for Best Alerts
The goal of an earthquake early warning (EEW) system is to provide an alert to people and automatic systems after an earthquake begins but before the shaking reaches their location. As the USGS and its partners are developing an EEW system, called ShakeAlert®, for the West Coast, the benefits, costs, capabilities, and limitations are being investigated. Two recent studies explored the...
Could the M7.1 Ridgecrest, CA Earthquake Sequence Trigger a Large Earthquake Nearby?
Release Date: SEPTEMBER 30, 2019
Two of the first questions that come to mind for anyone who just felt an earthquake are, “Will there be another one?” and “Will it be larger?”.
Loma Prieta Earthquake Professional Papers
The four Loma Prieta Earthquake Professional Papers, which were published as multiple chapters, comprehensively document the magnitude 6.9 earthquake in California that shook the San Francisco and Monterey Bay regions on October 17, 1989. They contain almost 3000 pages written by 401 investigators of the earthquake. The investigations were funded by a special Congressional appropriation to the...
Directions
Information to help you plan your visit to the Earthquake Science Center.
M7.9 1857 Fort Tejon Earthquake
The Last "Big One" in Southern California.
M6.9 October 17, 1989 Loma Prieta Earthquake
On October 17, 1989, at 5:04:15 p.m. (PDT), a magnitude 6.9 earthquake severely shook the San Francisco and Monterey Bay regions. The epicenter was located near Loma Prieta peak in the Santa Cruz Mountains, approximately 14 km (9 mi) northeast of Santa Cruz and 96 km (60 mi) south-southeast of San Francisco.
CoSMoS (Coastal Storm Modeling System) Central California v3.1 wave-hazard projections: 1-year storm in Santa Cruz County
This data contains maximum model-derived significant wave height (in meters) for the sea-level rise (SLR) and storm condition indicated.
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) scenar
CoSMoS (Coastal Storm Modeling System) Central California v3.1 water-level projections: average conditions in Santa Cruz County
This data contains model-derived total water levels (in meters) for the sea-level rise (SLR) and storm condition indicated.
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. Projecti
CoSMoS (Coastal Storm Modeling System) Central California v3.1 wave-hazard projections: 100-year storm in Santa Cruz County
This data contains maximum model-derived significant wave height (in meters) for the sea-level rise (SLR) and storm condition indicated.
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) scenar
CoSMoS (Coastal Storm Modeling System) Central California v3.1 ocean-currents projections: 20-year storm in Santa Cruz County
This data contains maximum model-derived ocean currents (in meters per second) for the sea-level rise (SLR) and storm condition indicated.
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) scen
CoSMoS (Coastal Storm Modeling System) Central California v3.1 flood depth and duration projections: 1-year storm in Santa Cruz County
This data contains maximum depth of flooding (cm) in the region landward of the present-day shoreline for the sea-level rise (SLR) and storm condition indicated.
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-le
CoSMoS (Coastal Storm Modeling System) Central California v3.1 ocean-currents projections: 100-year storm in Santa Cruz County
This data contains maximum model-derived ocean currents (in meters per second) for the sea-level rise (SLR) and storm condition indicated.
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) scen
CoSMoS (Coastal Storm Modeling System) Central California v3.1 ocean-currents projections: average conditions in Santa Cruz County
This data contains maximum model-derived ocean currents (in meters per second) for the sea-level rise (SLR) and storm condition indicated.
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) scen
Quaternary faults offshore of California
A comprehensive map of Quaternary faults has been generated for offshore of California. The Quaternary fault map includes mapped geometries and attribute information for offshore fault systems located in California State and Federal waters. The polyline shapefile has been compiled from previously published mapping where relatively dense, high-resolution marine geophysical data exist. The data...
Select borehole data for Anza Valley, Anza, CA
Borehole log number, State Well Number, location, construction information, and any wells tests performed on select wells from the Anza basin, Anza, CA. Also includes a lithologic data for a sub-set of borehole logs identified based on best coverage and representation of data within the study area.
SmeltCam sampling in San Joaquin River and False River near Jersey Island in the Sacramento-San Joaquin River Delta, California, 2016
This dataset includes field data for fishes sampled using mid-water trawls and the SmeltCam during daylight hours in the Sacramento- San Joaquin Delta, California. Sampling took place between February 8, 2016 and March 1, 2016. This data release includes all measured environmental parameters and fish taxa collected during sampling event.
Partitioning of six pyrethroid insecticides at varying salinities
To determine aqueous pyrethroid partitioning across a salinity gradient 20 mL Pyrex beakers were filled with 8 mL of deionized water at varying salinities (0, 0.5, 2, 6 ppt). Salinity was adjusted using a 10 ppt stock solution (made by diluting Instant Ocean into deionized water). The water samples were spiked with pyrethroids (bifenthrin, cyhalothrin, cyfluthrin, cypermethr
Otolith chemistry of fishes in Rodeo Lagoon, Marin County, California, 2016
The dataset includes multiple file types (CSV, ArcGIS shapefiles, and images), data relates to the elemental analysis of fish otoliths. Otoliths examined in this study were from randomly-sampled individual Tidewater Goby (Eucyclogobius newberryi) and Prickly Sculpin (Cottus asper) from the adult population of Rodeo Lagoon and Rodeo Creek, Marin County, California. The fish w
Mapping protected groundwater adjacent to oil and gas fields, San Joaquin Valley, California
Airborne electromagnetic (AEM) surveys are a major component of a regional study of groundwater quality adjacent to oil and gas fields in the San Joaquin Valley of California, USA. AEM resistivity models are being used to delineate groundwater salinity in an effort to locate groundwater adjacent to oil and gas fields that could have future...
Ball, Lyndsay B.; Gillespie, Janice M.; Minsley, Burke; Davis, Tracy; Landon, Matthew K. Quantifying post-wildfire hillslope erosion with lidar
Following a wildfire, flooding and debris- flow hazards are common and pose a threat to human life and infrastructure in steep burned terrain. Wildfire enhances both water runoff and soil erosion, which ultimately shape the debris flow potential. The erosional processes that route excess sediment from hillslopes to debris-flow channels in...
Rengers, Francis K.; McGuire, Luke
Application of the Stream Salmonid Simulator (S3) to the restoration reach of the Trinity River, California—Parameterization and calibration
Executive SummaryIn this report, we constructed and parameterized the Stream Salmonid Simulator (S3) for the 64-kilometer “Restoration Reach” of the Trinity River, just downstream of Lewiston Dam in northern California. S3 is a deterministic life-stage-structured population model that tracks daily growth, movement, and survival of juvenile salmon...
Perry, Russell W.; Jones, Edward C.; Plumb, John M.; Som, Nicholas A.; Hetrick, Nicholas J.; Hardy, Thomas B.; Polos, Joseph C; Martin, Aaron C.; Alvarez, Justin S.; De Juilio, Kyle P. Modeling morphodynamic development in the Alviso Slough system, South San Francisco Bay, California
Alviso Slough area, South San Francisco Bay, California, is the site of an ongoing effort to restore former salt production ponds to intertidal habitat. As restoration proceeds and the levees surrounding the former salt production ponds are breached, the increase in tidal prism and associated sediment scour in the sloughs will remobilize legacy...
Van der Wegen, Mick; Reyes, Johan; Jaffe, Bruce; Foxgrover, Amy
Emigration and transportation stress of juvenile Chinook salmon relative to their reintroduction upriver of Shasta Dam, California, 2017–18
The Bureau of Reclamation supports the Shasta Dam Fish Passage Evaluation (SDFPE; Yip, 2015) program, and in 2016 set out to determine the feasibility of reintroducing winter-run and spring-run Chinook salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss) to tributaries upstream of Shasta Dam. Ideally, reintroduction strategy includes...
Adams, Noah S.; Liedtke, Theresa L.; Plumb, John M.; Weiland, Lisa K.; Hansen, Amy C.; Evans, Scott D.
Reported investments in earthquake mitigation top $73 to $80 billion in the San Francisco Bay Area, California, since the 1989 Loma Prieta earthquake
The purpose of this report is to provide a compilation of structural retrofits and replacements of older buildings and infrastructure in the San Francisco Bay Area that have either been completed since 1989 or that are in progress as of October 2018. For the purposes of this report, all or parts of nine Bay Area counties were included:...
Brocher, Thomas M.; Gefeke, Kerri; Boatwright, John; Knudsen, Keith L.
Aeromagnetic map of Mountain Pass and vicinity, California and Nevada
Magnetic investigations of Mountain Pass and vicinity were begun as part of an effort to study regional crustal structures as an aid to understanding the geologic framework and mineral resources of the eastern Mojave Desert. The study area, which straddles the state boundary between southeastern California and southern Nevada, encompasses Mountain...
Ponce, David A.; Ponce, David A.; Denton, Kevin M.
Isostatic gravity map of Mountain Pass and vicinity, California and Nevada
Gravity investigations of Mountain Pass and vicinity were begun as part of an effort to study regional crustal structures as an aid to understanding the geologic framework and mineral resources of the eastern Mojave Desert. The study area, which straddles the state boundary between southeastern California and southern Nevada, encompasses Mountain...
Ponce, David A.; Ponce, David A.; Denton, Kevin M.
Geophysical and geologic maps of Mountain Pass and vicinity, California and Nevada
U.S. Geological Survey Scientific Investigations Map 3412 is a series of products that consists of geophysical and geologic maps of Mountain Pass and vicinity, California. Maps A and B (red outline in above map image) are gravity and aeromagnetic maps, respectively. The map series was begun as part of an effort to study regional crustal structures...
Ponce, David A. Improving earthquake rupture forecasts using California as a guide
This article discusses ways in which earthquake rupture forecast models might be improved. Because changes are most easily described in the context of specific models, the third Uniform California Earthquake Rupture Forecast (UCERF3) and its presumed successor, UCERF4, is used as a basis for discussion. Virtually all of the issues and possible...
Field, Edward H. Increasing earthquake insurance coverage in California via parametric hedges
California has the highest earthquake risk of any state in the United States. The Federal Emergency Management Agency (FEMA) reported in 2017 that 73% of the nation’s annual losses to earthquakes were expected to be concentrated in California and the Pacific Northwest. California alone constitutes 61% ($3.7 billion out of an estimated $6.1 billion...
Franco, Guillermo; Tirabassi, G; Lopeman, M; Wald, David J.; Siembieda, W.J. State transportation agencies partner to deploy and enhance ShakeCast
The California Department of Transportation (Caltrans) is organizing and leading a three-year Transportation Pooled Fund (TPF) project, Connecting the Dots: Implementing ShakeCast Across Multiple State Departments of Transportation for Rapid Post-Earthquake Response. Ten state Departments of Transportation (DOT)—CA, ID, MO, MS, OK, OR, SC, TX, UT...
Turner, L.; Wald, David J.; Lin, Kuo-wan; Chiou, Brian; Slosky, Daniel
Wintering Waterfowl at Sacramento National Wildlife Refuge
In this video, you can hear the honks and quacks of geese and ducks ring through the air, as birds fly in every direction above a wetland. This video was captured at Sacramento National Wildlife Refuge in November 2019, not long after geese and ducks began to arrive to spend the winter in the California Central Valley.
2019 November Public Lecture
2019 November Public Lecture Flyer
Sea-Level Rise, Extreme Water Levels, and Coastal Erosion ... How bad could it possibly be?
By Sean Vitousek, USGS Research Oceanographer
- Sea-level rise represents an unprecedented civil engineering challenge.
- Small amounts of sea-level rise can disproportionately increase the frequency
Chirp rests on the deck of R/V Bold Horizon
This instrument, the Edgetech SB-516 or "chirp", emits acoustic signals that penetrate the sediment on the seafloor. The reflected sound is recorded and is used to create a cross-section image, or profile, of the sub-bottom.
Klamath River mouth
A view of the mouth of the Klamath River where it meets the Pacific Ocean in northern California. The river runs from Oregon to California. Four dams along the Klamath are pending removal. USGS is studying coastal watershed response to dam removal, including long-term before-after/control-impact (BACI) studies.
Initial Observations of Cypress Structure Collapse, Oakland, CA 1989
Retrospective interview with USGS Geophysicist Susan Hough about the collapse of the Nimitz Freeway (known as the Cypress Structure) in Oakland, CA, during the October 17, 1989 Loma Prieta Earthquake and how the first responders reacted to the event.
Sight Response and Cypress Structure Collapse, Oakland, CA 1989
Retrospective interview with USGS Geophysicist Susan Hough about her early earthquake work during the 1989 Loma Prieta earthquake. The interview covers how the Cypress Structure collapse in Oakland, CA, served as a site response study for seismic research.
The Great California ShakeOut (2019) Role Play Exercise - Biola Univ.
Each year the State of California promotes a ShakeOut event where local citizens practice earthquake response and preparedness. This video shows footage from the 2019 Great California ShakeOut, which was hosted at Biola University in La Mirenda, CA. Video includes footage of the initial ShakeAlert announcement that blared across campus. Additional footage includes first
Groundwater-level Response to the July 2019 Ridgecrest, CA Earthquakes
Locations of the July 2019 earthquake epicenters and six USGS groundwater-monitoring sites. The hydrographs show the response of groundwater levels to the earthquakes. Sites shown are California (1)
...
Rossfelder P-5 Vibracorer
USGS science crew from Pacific Coastal and Marine Science Center work together to get the vibracorer coring device in position to collect sediment core samples off San Francisco, California.
Vibracorer on deck
The Rossfelder P-5 vibracorer, with its polybuterate liner visible, is secured on the deck of the research vessel Bold Horizon, awaiting deployment off the coast of California just north of San Francisco. More liners are stored in a cage off to the side.
Vibracorer on deck in San Francisco
The USGS uses the Rossfelder P-5 vibracorer to collect deep-water sediment samples from the seafloor. Here, they are heading out offshore of San Francisco with the Golden Gate Bridge in the background.
October 17, 1989 (Part 4)
On October 17, 1989, at 5:04 pm a magnitude M6.9 earthquake struck near Loma Prieta, California. It was a tragic reminder of the destructive power of earthquakes. However, it was also a watershed moment in seismic research. 30 years later, we revisit the earthquake through the eyes of the scientists who experienced it. And studied it. These are their stories. In Part 4 (of
An earthquake swarm started on the evening of July 5 at the southern margin of Coso Volcanic Field in Inyo County, California.
SACRAMENTO – A new study shows how giant gartersnakes use Central Valley rice fields
California Water Science Center Research Hydrologist Dr. Judith Drexler and others have published an article in the journal Restoration Ecology, observing the progress of a restored salt marsh in southern Puget Sound, Washington.
California Water Science Center (CAWSC) hydrologists Joseph Hevesi, Scott Wright, Alexandra Etheridge, Mathieu Marineau, and Michelle Stern will discuss their research at the 2019 Federal Interagency Sedimentation and Hydrologic Modeling (SEDHYD) Conference in Reno, Nevada.
Dr. Christina Kellogg (Research Microbiologist, SPCMSC) is a member of the judging panel that will award winners of the $7 million dollar Shell Ocean Discovery XPRIZE during the final award announcement at the Musée Océanographique de Monaco on May 31.
Schools are welcome to contact USGS about tours in Santa Cruz, California.
A new study shows that mysterious cycles in salinity in the lower Colorado River are a result of precipitation patterns in the headwaters of the upper basin more than a thousand river miles away. The salinity levels generally repeat about every 10 years.
Scientists at the volcano observatories of the U.S. Geological Survey pay close attention to volcanoes of the Cascade Range, Alaskan Peninsula and Aleutian Arc.
In less than 30 years the combination of sea-level rise plus an extreme storm along California’s coast could flood more than 150,000 residents and impact over $30 billion in property value. By 2100, up to 600,000 people and $150 billion in property could be at risk from coastal flooding.
Meet the new researchers at the USGS Pacific Coastal and Marine Science Center in Santa Cruz, California
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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