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: 408
Date published: August 19, 2020
Status: Active

Remote Sensing Coastal Change

We use remote-sensing technologies—such as aerial photography, satellite imagery, structure-from-motion (SfM) photogrammetry, and lidar (laser-based surveying)—to measure coastal change along U.S. shorelines.

Date published: August 18, 2020
Status: Completed

2019 Regional geophysical surveys of northern and central Cascadia (offshore Washington and Oregon)

Geophysical data collected offshore of Washington and Oregon in 2019, a USGS-University of Washington partnership

Contacts: Janet Watt
Date published: August 18, 2020
Status: Completed

2018 Regional geophysical surveys of southern Cascadia (offshore northern California and southern Oregon)

Regional geophysical surveys conducted offshore of northern California and southern Oregon in 2018, a USGS-Humboldt State University partnership

Contacts: Janet Watt
Date published: August 18, 2020
Status: Active

CoSMoS-Groundwater

The USGS Coastal Storm Modeling System (CoSMoS) team has extensively studied overland flooding and coastal change due to rising seas and storms. Interactions with coastal stakeholders have elucidated another important question; will rising seas also intrude into coastal aquifers and raise groundwater...

Contacts: Patrick Barnard
Date published: August 14, 2020
Status: Completed

2018 USGS-NOAA multibeam bathymetry surveys

Multibeam bathymetric surveys conducted offshore of Oregon and northern California in 2018, a USGS-NOAA partnership

Contacts: Janet Watt
Date published: August 13, 2020
Status: Active

SWATHplus 234kHz

The ITER Systems SWATHplus 234 kHz is an interferometric bathymetric survey tool for surveys in water depths from 1 to 200 meters.

Date published: August 12, 2020
Status: Active

Ecosystems: EXPRESS

The continental shelf and slope offshore California, Oregon, and Washington are home to deep-sea corals, chemosynthetic communities, and other sensitive habitats that could be impacted by the development of energy and mineral resources. The EXPRESS campaign will map and...

Date published: August 5, 2020
Status: Active

Evaluating the effects of wastewater-derived nutrients on phytoplankton abundance and community structure in the San Francisco Estuary and Delta

Planned upgrades to the Sacramento Regional wastewater treatment plant (SRWTP) will substantially reduce nutrient discharge and also alter the types and amounts of nutrients being distributed across the San Francisco Delta and Estuary (Delta).

One highly anticipated outcome of lower nutrients is improved productivity in the phytoplankton communities that supply aquatic food webs, which...

Date published: July 28, 2020
Status: Active

U.S. West Coast and Alaska Marine Geohazards

Marine geohazards are sudden and extreme events beneath the ocean that threaten coastal populations. Such underwater hazards include earthquakes, volcanic eruptions, landslides, and tsunamis.

Devastating earthquakes in Japan (2011) and Chile (2010) that spawned pan-oceanic tsunamis sent a sobering reminder that U.S. coastlines are also vulnerable to natural disasters that originate in...

Date published: July 27, 2020
Status: Active

Seafloor Faults off Southern California

More than 22 million people live along Southern California’s coast, and many more migrate there every year. Faults and earthquake threats in this region have been heavily studied on land. USGS aims to boost our knowledge about faults on the seafloor, so they can be included in hazard assessments.

Contacts: Danny Brothers
Date published: July 27, 2020
Status: Active

Underwater Landslides off Southern California

An earthquake can trigger a landslide along the ocean floor, which can then set off a tsunami. Without modern, high-resolution imaging of the seafloor, many historical slides and threats from future slides remain undetected.

Contacts: Jared Kluesner
Filter Total Items: 527
Date published: May 18, 2020

Sediment transport and aquatic vegetation data from three locations in the Sacramento-San Joaquin Delta, California, 2017 to 2018

We measured currents, suspended-sediment concentration, bed sediment characteristics, and vegetation biomass density in the Sacramento-San Joaquin Delta in 2017-2018, as part of a project investigating the influence of invasive aquatic vegetation on flow and sediment flux. This data release includes data from three sites: Lindsey Slough, Middle River, and lower Mokelumne River.

Date published: May 18, 2020

Hydrodynamic time-series data from three locations in the Sacramento-San Joaquin Delta, California, 2017 to 2018

Hydrodynamic and sediment transport time-series data, including water depth, velocity, turbidity, conductivity, and temperature, were collected by the U.S. Geological Survey (USGS) Pacific Coastal and Marine Science Center at three locations in the Sacramento-San Joaquin Delta. Data were collected in Lindsey Slough in April 2017, and Middle River and the Mokelumne River in March

Date published: May 18, 2020

Swath bathymetric data from three locations in the Sacramento-San Joaquin Delta, California, 2017 to 2018

This part of the data release contains high-resolution swath bathymetry data collected by the U.S. Geological Survey (USGS) Pacific Coastal and Marine Science Center at three locations in the Sacramento-San Joaquin Delta. Data were collected in Lindsey Slough in April 2017, Middle River in March 2018, and Mokelumne River in March 2018 using an interferometric bathymetric sidescan sonar sy

Date published: May 18, 2020

Acoustic-backscatter data from three locations in the Sacramento-San Joaquin Delta, California, 2017 to 2018

This part of the data release contains high-resolution acoustic-backscatter data collected by the U.S. Geological Survey (USGS) Pacific Coastal and Marine Science Center at three study locations in the Sacramento-San Joaquin Delta, California. Data were collected in Lindsey Slough in April 2017, Middle River in March 2018, and Mokelumne River in March 2018, using an interferometric ba

Date published: May 18, 2020

Vegetation biomass and density from three locations in the Sacramento-San Joaquin Delta, California, 2017 to 2018

Vegetation type and density data were collected by the U.S. Geological Survey (USGS) Pacific Coastal and Marine Science Center at three locations in the Sacramento-San Joaquin Delta. Data were collected in Lindsey Slough in April 2017, and Middle River and the Mokelumne River in March 2018. Vegetation samples were collected by divers, and used to determine dry biomass density. These data

Date published: May 18, 2020

Suspended particle size distribution data from three locations in the Sacramento-San Joaquin Delta, California, 2017 to 2018

These data present suspended particle size distributions collected by the U.S. Geological Survey (USGS) Pacific Coastal and Marine Science Center at three locations in the Sacramento-San Joaquin Delta. Data were collected in Lindsey Slough on April 4 and April 18, 2017, and near the mouth of the Mokelumne River and in Middle River on March 14, 2018 by deploying a Sequoia Scientific Lase

Date published: May 18, 2020

Grain size, bulk density, and organic carbon of sediment cores from three locations in the Sacramento-San Joaquin Delta, California, 2017 to 2018

Bed sediment samples were collected in Lindsey Slough in April 2017, and Middle River and the Mokelumne River in March 2018, to analyze for sediment properties, including bulk density, particle size distribution, and percent organic carbon. Sediment samples were collected within the vegetation with push corers deployed from a small vessel, and in the unvegetated channel with a Gomex b

Date published: May 4, 2020

Coastal Storm Modeling System (CoSMoS) for Central California, v3.1

This dataset contains spatial projections of coastal cliff retreat (and associated uncertainty) for future scenarios of sea-level rise (SLR) in Central California. Present-day cliff-edge positions used as the baseline for projections are also included. Projections were made using numerical models and field observations as part of Coastal Storm Modeling System (CoSMoS). Read metadata carefully...

Date published: May 4, 2020

Coastal Storm Modeling System (CoSMoS)

CoSMoS makes detailed predictions over large geographic scales of storm-induced coastal flooding and erosion for both current and future SLR scenarios, as well as long-term shoreline change and cliff retreat. Several versions of CoSMoS have been implemented for areas of the California coast, including Southern California, Central California, and San Francisco Bay.

Date published: May 4, 2020

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

Date published: May 4, 2020

CoSMoS (Coastal Storm Modeling System) Central California v3.1 flood depth and duration projections: 100-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

Date published: May 4, 2020

CoSMoS (Coastal Storm Modeling System) Central California v3.1 water-level projections: 1-year storm 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

Filter Total Items: 43
Figure 6 for Southwestern Willow Flycatcher Habitat Viewer webpage
August 8, 2016

Figure 6. Map showing changes in predicted flycatcher habitat along the upper Gila River after conducting a tamarisk leaf beetle-impact simulation. The upper Gila River was divided into nine zones in order to quantify changes. A satellite model was used to predict flycatcher habitat at a 40-percent probability threshold.

Figure 5 for Southwestern Willow Flycatcher Habitat Viewer webpage
August 8, 2016

Figure 5. Map showing changes in predicted flycatcher habitat along the lower Virgin River, Nevada and Arizona, 2010–2015, as determined from a satellite model at a 40-percent probability threshold.

Figure 3 for Southwestern Willow Flycatcher Habitat Viewer webpage
August 8, 2016

Map showing relative changes in predicted flycatcher habitat, as determined from a satellite model at a 40-percent probability threshold, Southwestern United States, 2013–15.

Figure 2 for Southwestern Willow Flycatcher Habitat Viewer webpage
August 8, 2016

Map showing area of predicted flycatcher breeding habitat (averaged across 2013–15) at all elevations in 6,521 U.S. Geological Survey 7.5-minute quadrangles, Southwestern United States. Only areas within a prescribed distance of streams and greater than stream-order 3, or within 1 kilometer of a lake or reservoir, were included in this analysis.

Figure 1 for Southwestern Willow Flycatcher Habitat Viewer webpage
August 8, 2016

Figure 1. Maps showing location of the project area and the 35 U.S. Fish and Wildlife Service Southwestern Willow Flycatcher management unit boundaries, designated critical-habitat reaches, and waterbodies considered by the satellite model for regionwide modeling, Southwestern United States.

Digital Elevation Model in the Atchafalaya Basin, LA
April 19, 2016

The 3DEP products and services available through The National Map consist of standard digital elevation models (DEMs) at various horizontal resolutions, elevation source and associated datasets, an elevation point query service and bulk point query service. All 3DEP products are available, free of charge and without use restrictions.

Filter Total Items: 374
Publication Thumbnail
Year Published: 2019

Occurrence and sources of radium in groundwater associated with oil fields in the southern San Joaquin Valley, California

Geochemical data from 40 water wells were used to examine the occurrence and sources of radium (Ra) in groundwater associated with three oil fields in California (Fruitvale, Lost Hills, South Belridge). 226Ra+228Ra activities (range=0.010-0.51 Bq/L) exceeded the 0.185 Bq/L drinking-water standard in 18% of the wells (not drinking-water wells)....

McMahon, Peter B.; Avner Vengosh; Davis, Tracy; Landon, Matthew K.; Rebecca L. Tyne; Wright, Michael; Kulongoski, Justin T.; Hunt, Andrew G.; Peter H. Barry; A.J. Kondash; Z. Wang; Christopher J. Ballentine
McMahon, P.B., A. Vengosh, T.A. Davis, M.K. Landon, R.L. Tyne, M.T. Wright, J.T. Kulongoski, A.G. Hunt, P.H. Barry, A.J. Kondash, Z. Wang, C.J. Ballentine, 2019. Occurrence and sources of radium in groundwater associated with oil fields in the southern San Joaquin Valley, California. Environmental Science & Technology, 53, 9398-9406.

Publication Thumbnail
Year Published: 2019

Preliminary report on engineering and geological effects of the July 2019 Ridgecrest earthquake sequence

The Ridgecrest Earthquake sequence included a foreshock event on July 4 2019 (M6.4) and a M7.1 mainshock event on July 5 2019. These events occurred in the Eastern California Shear Zone, near Indian Wells Valley, south of China Lake and west of Searles Valley. GEER has partnered with several organizations to collect perishable data and document...

Stewart, Jonathan P.; Brandenberg, Scott J; Wang, Pengfei; Nweke, Chukwuebuka C; Hudson, Kenneth; Mazzoni, Silvia; Bozorgnia, Yousef; Hudnut, Kenneth W.; Davis, Craig A.; Ahdi, Sean K; Zareian, Farzin; Fayaz, Jawad; Koehler, Richard D; Chupik, Colin; Pierce, Ian; Williams, Alana; Akciz, Sinan; Hudson, Martin B; Kishida, Tadahiro; Brooks, Benjamin A.; Gold, Ryan D.; Ponti, Daniel J.; Scharer, Katherine; McPhillips, Devin; Duross, Christopher; Ericksen, Todd; Hernandez, Janis; Patton, Jay; Olson, Brian; Dawson, Timothy E.; Treiman, Jerome; Blake, Kelly; Buchhuber, Jeffrey; Madugo, Chris L M; Sun, Joseph; Donnellan, Andrea; Lyzenga, Greg; Conway, Erik
Stewart, J.P. (ed.), Brandenberg, S.J., Wang, Pengfei, N., Chukwuebuka C., Hudson, K., Mazzoni, S., Bozorgnia, Y., Hudnut, K.W., Davis, C.A., Ahdi, S.K., Zareian, F., Fayaz, J., Koehler, R.D., Chupik, C., Pierce, I., Williams, A., Akciz, S., Hudson, M.B., Kishida, T., Brooks, B.A., Gold, R.D., Ponti, D.J., Scharer, K.M., McPhillips, D.F., Ericksen, T.., Hernandez, J., Patton, J., Olson, B., Dawson, T., Treiman, J., Duross, C.B., Blake, K., Buchhuber, J., Madugo, C., Sun, J., Donnellan, A., Lyzenga, G., and Conway, E., 2019, Preliminary report on engineering and geological effects of the July 2019 Ridgecrest Earthquake sequence: Geotechnical Extreme Event Reconnaissance Association Report GEER-064, https://doi.org/10.18118/G6H66K.

Publication Thumbnail
Year Published: 2019

Offshore shallow structure and sediment distribution, Point Sur to Point Arguello, central California

This publication consists of three map sheets that display shallow geologic structure, along with sediment distribution and thickness, for an about 225-km-long offshore section of the central California coast between Point Sur and Point Arguello. Each map sheet includes three maps, at scales of either 1:150,000 or 1:200,000, as well as a set of...

Johnson, Samuel Y.; Hartwell, Stephen R.; Watt, Janet T.; Beeson, Jeffrey W.; Dartnell, Peter
Johnson, S.Y., Hartwell, S.R., Watt, J.T., Beeson, J.W., and Dartnell, P., 2019, Offshore shallow structure and sediment distribution, Point Sur to Point Arguello, central California: U.S. Geological Survey Open-File Report 2018–1158, 3 sheets, scales 1:150,000 and 1:200,000, https://doi.org/10.3133/ofr20181158.

Publication Thumbnail
Year Published: 2019

Widespread initiation, reactivation, and acceleration of landslides in the northern California Coast Ranges due to extreme rainfall

Episodically to continuously active slow-moving landslides are driven by precipitation. Climate change, which is altering both the frequency and magnitude of precipitation world21 wide, is therefore predicted to have a major impact on landslides. Here we examine the behavior of hundreds of slow-moving landslides in northern California in...

Handwerger, Alexander L.; Fielding, Eric J.; Huang, Mong-Han; Bennett, Georgina L.; Liang, Cunren; Schulz, William

Publication Thumbnail
Year Published: 2019

Event detection performance of the PLUM earthquake early warning algorithm in southern California

We test the Japanese ground‐motion‐based earthquake early warning (EEW) algorithm, propagation of local undamped motion (PLUM), in southern California with application to the U.S. ShakeAlert system. In late 2018, ShakeAlert began limited public alerting in Los Angeles to areas of expected modified Mercalli intensity (⁠IMMI⁠) 4.0+ for magnitude 5.0...

Cochran, Elizabeth S.; Bunn, Julian; Minson, Sarah E.; Baltay, Annemarie S.; Kilb, Deborah L.; Kodera, Y.; Hoshiba, Mitsuyuki

Publication Thumbnail
Year Published: 2019

An evaluation of debris-flow runout model accuracy and complexity in Montecito, CA: Towards a framework for regional inundation-hazard forecasting

Numerous debris-flow inundation models have been applied retroactively to noteworthy events around the world. While such studies can be useful in identifying controlling factors, calibrating model parameters, and assessing future hazards in specific study areas, model parameters tailored to individual events can be difficult to apply regionally....

Bessette-Kirton, Erin; Kean, Jason W.; Coe, Jeffrey A.; Rengers, Francis K.; Staley, Dennis M.
Bessette-Kirton, E.K., Kean, J.W., Coe, J.A., Rengers, F.K., Staley, D.M., 2019, An evaluation of debris-flow runout model accuracy and complexity in Montecito, California: Towards a framework for regional inundation-hazard forecasting, in Kean, J.W., Coe, J.A., Santi, P.M., and Guillen, B.K., eds., Debris-Flow Hazards Mitigation: Mechanics, Monitoring, Modeling, and Assessment, Proceedings of the 7th International Conference on Debris Flow Hazards Mitigation, Golden, Colorado p. 257-264.

Publication Thumbnail
Year Published: 2019

Taking the pulse of debris flows: Extracting debris-flow dynamics from good vibrations in southern California and central Colorado

The destructive nature of debris flows makes it difficult to quantify flow dynamics with direct instrumentation. For this reason, seismic sensors placed safely away from the flow path are often used to identify the timing and speed of debris flows. While seismic sensors have proven to be a valuable tool for event detection and early warning, their...

Michel, A.; Kean, Jason W.; Smith, Joel B.; Allstadt, Kate E.; Coe, Jeffrey A.
Michel, A., Kean, J.W., Smith, J.B., Allstadt, K., and Coe, J.A. (2019), Taking the pulse of debris flows: extracting debris-flow dynamics from good vibrations in southern California and central Colorado, in Debris-Flow Hazards Mitigation: Mechanics, Monitoring, Modeling, and Assessment, edited by Kean, J.W., Coe, J.A., Santi, P.M., and Guillen, B.K., Association of Environmental and Engineering Geologists, Special Publication #28, p. 154-161.

Publication Thumbnail
Year Published: 2019

Inundation, flow dynamics, and damage in the 9 January 2018 Montecito Debris-Flow Event, California, USA: Opportunities and challenges for post-wildfire risk assessment

Shortly before the beginning of the winter rainy season, one of the largest fires in California history (Thomas Fire) substantially increased the susceptibility of steep slopes in Santa Barbara and Ventura Counties to debris flows. On January 9, 2018, before the fire was fully contained, an intense burst of rain fell on the portion of the burn...

Kean, Jason W.; Staley, Dennis M.; Lancaster, Jeremy T.; Rengers, Francis K.; Swanson, Brian J.; Coe, Jeffrey A.; Hernandez, Janis; Sigman, Aaron; Allstadt, Kate E.; Lindsay, Donald N.

Publication Thumbnail
Year Published: 2019

Ground-motion residuals, path effects, and crustal properties: A pilot study in southern California

To improve models of ground motion estimation and probabilistic seismic hazard analyses, the engineering seismology field is moving toward developing fully nonergodic ground motion models, models specific for individual source‐to‐site paths. Previous work on this topic has examined systematic variations in ground‐motion along particular paths (...

Sahakian, Valerie J.; Baltay, Annemarie S.; Hanks, Thomas C.; Bueler, Janine; Vernon, Frank; Kilb, Deborah L.; Abrahamson, Norm A.
Sahakian, V. J., Baltay, A., Hanks, T. C., Buehler, J., Vernon, F. L., Kilb, D., & Abrahamson, N. A. ( 2019). Ground motion residuals, path effects, and crustal properties: A pilot study in Southern California. Journal of Geophysical Research: Solid Earth, 124, 5738– 5753. https://doi.org/10.1029/2018JB016796

Publication Thumbnail
Year Published: 2019

A revised continuous surface elevation model for modeling

A digital elevation model (DEM) is an essential component of any hydrodynamic model. The Delta Modeling Section (Section) has maintained a database of bathymetry soundings and levee surveys for decades and published a 10-meter (10m) DEM for the San Francisco Bay and Sacramento-San Joaquin Delta (Delta) (California Department of Water Resources...

Wang, Rueen-Fang; Ateljevich, Eli; Fregoso, Theresa A.; Jaffe, Bruce E.

Publication Thumbnail
Year Published: 2019

Discovery of an extensive deep-sea fossil serpulid reef associated with a cold seep, Santa Monica Basin, California

Multi-beam mapping of the Santa Monica Basin in the eastern Pacific has revealed the existence of a number of elevated bathymetric features, or mounds, harboring cold seep communities. During 2013-2014, mounds at ~600 m water depth were observed for the first time and sampled by Monterey Bay Aquarium Research Institute’s ROV Doc Ricketts. Active...

Georgieva, Magdalena N; Paull, Charles K.; Little, Crispin TS; McGann, Mary; Sahy, Diana; Condon, Daniel; Lundsten, Lonny; Pewsey, Jack; Caress, David W; Vrijenhoek, Robert C
Georgieva, M.N., Paull, C.K., Little, C.T.S., McGann, M., Sahy, D., Condon, D., Lundsten, L., Pewsey, J., Caress, D.W., and Vrijenhoek, R.C., 2019, Discovery of an extensive deep-sea fossil serpulid reef associated with a cold seep, Santa Monica Basin, California: Frontiers in Marine Science, https://doi.org/10.3389/fmars.2019.00115.

Publication Thumbnail
Year Published: 2019

Characterizing the catastrophic 2017 Mud Creek Landslide, California, using repeat Structure-from-Motion (SfM) photogrammetry

Along the rugged coast of Big Sur, California, the Mud Creek landslide failed catastrophically on May 20, 2017 and destroyed over 400 m of scenic California State Highway 1. We collected structure-from-motion (SfM) photogrammetry data using airborne platforms that, when combined with existing airborne lidar data, revealed that the area exhibited...

Warrick, Jonathan; Ritchie, Andrew C.; Reid, Mark E.; Schmidt, Kevin M.; Logan, Joshua B.

Filter Total Items: 1,045
A structure made of wooden pilings with a platform around the top stands in water with fog and hills in the far background.
January 22, 2020

Grizzly Bay dolphin with weather station installed on top

A structure called a dolphin, permanently affixed in the sediment, stands in Grizzly Bay near San Francisco, CA, with a weather station installed on top. The USGS will use the data from the weather station in conjunction with other oceanographic data, in their studies of sediment movement in the bay.

A nondescript white instrument box sits up high atop piers in the water with cables and a small solar panel.
January 22, 2020

Weather station power supply and modem

A weather station, installed in the middle of Grizzly Bay east of San Pablo Bay (near San Francisco), gets its power from a small solar panel. Data collected from the station is transmitted via a wireless modem. Far in the background is the city of Benicia, and the plume rising into the sky is water vapor emitted from the Benicia oil refinery.

A boat floats on calm waters with some people sitting in it.
January 22, 2020

Sampling on Grizzly Bay

On PCMSC vessel Jewell, a team of USGS scientists sit in Grizzly Bay, a baylet of San Francisco Bay in Solano County, California. USGS collects sediment samples to study how sediment moves through sensitive coastal environments like this.

A photograph shows a boat sitting at a dock, with tall grasses in the foreground and the setting sun in the distance.
January 22, 2020

Preparing for a day of sampling on Grizzly Bay

Scientists from the USGS Pacific Coastal and Marine Science Center in their vessel jewell, docked at Belden's Landing Water Access Facility on Montezuma Slough. They are preparing for a day of sampling on Grizzly Bay, where they study how sediment moves through sensitive coastal environments.

People sit in a small boat floating the water, preparing a sampling device to collect sediment from the bottom of the water.
January 22, 2020

Preparing the GOMEX on Grizzly Bay

From left to right, USGS scientists Sam McGill, Lucas WinklerPrins, David Hart, Selina Davila Olivera, and Pete Dal Ferro work on Grizzly Bay on the vessel Jewell, to collect sediment samples using the GOMEX box corer.

Five people on a small boat in calm water work on a sampling device being retrieved from the water.
January 22, 2020

Sediment collected in a GOMEX box corer

USGS science crew works to free the muddy sediment from a GOMEX box corer. They are on board the Pacific Coastal and Marine Science Center's vessel Jewell on Grizzly Bay in the San Francisco Bay area.

Illustration of a bay and delta region with different colors to depict varying depths of water.
January 17, 2020

Bathymetric map of the northern portion of San Francisco Bay (MLLW)

Digital elevation model (DEM) of northern San Francisco Bay, California, created using bathymetry data collected between 1999 and 2016 (MLLW)

Photo of a rugged coastline with bluffs, gentle waves, and rocks jutting out from the sand.
January 16, 2020

California coastline

The U.S. west coast is an area of complex coastal geography. This photograph depicts several examples of geological features along the California coastline that are shaped by varied coastal processes. The gently sloping beach, stark bluffs, and presence of smooth rocks suggests that the coastal processes shaping this coastline are complex.

Photo of a coastline where sections of bluff have eroded into a network of small gullies in a dendritic pattern.
January 16, 2020

California coastal erosion

This region of the California coastline is lined with coastal bluffs that have been shaped not only by runoff from rain, but also by wave- and wind-driven erosion. This photo from Pescadero State Beach displays an example of a bluff undergoing erosional processes. Water from the ocean, delivered in waves, can overtop some of these coastal bluffs. As water runs off the

...
map of Indian Wells Valley displaying subbasin boundaries and shaded by recharge in mm/year
December 31, 2019

Natural Recharge (1981 - 2010), Indian Wells Valley, CA

The USGS California Basin Characterization Model (BCM) was used to understand the rate and amounts of natural groundwater recharge in the Indian Wells Valley and to refine historical estimates of groundwater recharge in the valley. Results from this study provide validation of recharge estimates

...
Illustration helps visualize the seafloor character showing canyons and and the rivers that form them.
December 31, 2019

Southern Cascadia topography and bathymetry

Topography and bathymetry of southern Cascadia, which includes southern Oregon and northern California (seafloor depths between 200 and 3000 m are shown in the spectrum color scale from red (shallower) to purple (deeper). The land and continental shelf are shown in grayscale slope shading where darker colors represent steeper slopes. Green lines are locations of known

...
Thurston Lake and Mount Konocti, Clear Lake Volcanic Field
December 16, 2019

Thurston Lake and Mount Konocti, Clear Lake Volcanic Field

Thurston Lake and Mount Konocti, Clear Lake Volcanic Field, California.

Filter Total Items: 946
Dr. Barnard
December 5, 2019

Briefing held on science and policy initiatives that are helping protect West Coast ecosystems and communities from erosion, sea level rise, and other coastal hazards.

USGS scientist Nancy Prouty collects deep-sea water samples as part of the EXPRESS 2019 expedition
October 30, 2019

Keep up to speed with the latest USGS deep-sea research cruise with this seafloor syntax.

A crowd of about 20 people stand facing a ship docked along a pier.
October 21, 2019

Expanding Pacific Research and Exploration of Submerged Systems (EXPRESS) Expedition Team Hosts National Oceanic and Atmospheric Administration (NOAA), USGS, and Bureau of Ocean Energy Management (BOEM) Leadership on October 21, 2019, in San Francisco

gray-scale map of San Francisco Bay area
October 17, 2019

Today, the U.S. Geological Survey and the State of California pressed the “go” button to allow the first-ever statewide public testing of the California Early Earthquake Warning System, which is powered by USGS’s earthquake early warning alerts, called ShakeAlerts.

vertical timeline with text bullets
October 17, 2019

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...

Read the new Science for Everyone article at What if the ShakeAlert Earthquake Early Warning System Had Been Operating During the M6.9 1989 Loma Prieta Earthquake?

Deep-sea organisms
October 16, 2019

Keep up to speed with the latest USGS deep-sea research cruise with this seafloor syntax.

ROV control room
October 16, 2019

Keep up to speed with our EXPRESS research cruise with this latest seafloor syntax!

aerial view of road damage after the Ridgecrest, CA earthquake
October 15, 2019

Effects from the two July 2019 Ridgecrest, CA earthquakes were observed in several USGS continuous groundwater-level monitoring sites in California, Nevada, and Arizona.

satellite image of wildfires in Southern California, featuring big smoke plumes extending out from the coast
October 10, 2019

Two new publications underscore the role of wind in destructive California wildfires

Ground view of collapsed building and burned area, Beach and Divisadero Sts., Marina District.
October 7, 2019

Next week, USGS and the nation commemorate the 30th anniversary of one of the most destructive earthquake disasters in U.S. history – the 1989 Loma Prieta earthquake in northern California. The magnitude 6.9 quake struck on October 17 in the southern portion of the San Francisco Bay Area near Santa Cruz and was responsible for the deaths of 63 people and more than 3,500 injuries.

Filter Total Items: 237