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: 416
Date published: August 19, 2020
Status: Completed

2019 Seafloor Geodesy cruise

Performed maintenance on and retrieved data from seafloor geodetic instrument arrays offshore of Oregon and northern California in 2019, a USGS-Scripps-University of Washington-University of Hawaii partnership

Contacts: Janet Watt
Date published: August 19, 2020
Status: Completed

2019 USGS-NOAA Multibeam Bathymetry

Multibeam bathymetric surveys conducted offshore of Oregon and northern California in 2019, a USGS-NOAA partnership

Contacts: Peter Dartnell
Date published: August 19, 2020
Status: Completed

3-D Geologic and Seismic Velocity Models of the San Francisco Bay Region

The USGS 3-D Geologic and Seismic Velocity Models of the San Francisco Bay region provide a three-dimensional view of the geologic structure and physical properties of the region down to a depth of 45 km (28 miles). Construction of this 3D Bay Area model has been a joint effort of the USGS Earthquake Hazards Program and the...

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 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: August 3, 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
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 23, 2020
Status: Active

California Sand Resource Assessment Project

The USGS is working in partnership with the Bureau of Ocean Energy Management (BOEM) and the State of California Ocean Protection Council (OPC) to evaluate sand and gravel resources in Federal and State waters for potential use in future beach nourishment projects.  Prior to the leasing and development of outer continental shelf (OCS) sand resources for use in beach restoration or coastal...

Contacts: Jonathan Warrick, Mark Leung
Filter Total Items: 550
Date published: July 6, 2020

Chirp sub-bottom data of USGS field activity 2018-645-FA collected in the Santa Barbara Channel in July of 2018

High-resolution chirp sub-bottom data were collected by the U.S. Geological Survey in July of 2018 between Point Conception and Coal Oil Point in the Santa Barbara Channel, California. Data were collected aboard the USGS R/V Parke Snavely during field activity 2018-645-FA, using an EdgeTech SB-512i sub-bottom profiler. Sub-bottom acoustic penetration spans several tens of meters and is vari...

Date published: July 5, 2020

Bed sediment properties in Little Holland Tract and Liberty Island, Sacramento-San Joaquin Delta, California, 2014 to 2019 (ver. 2.0, May 2020)

Bed sediments were collected in two submerged agricultural tracts. Samples were analyzed for grain size distribution, bulk density, or both, from multiple locations during surveys from 2014-2019. This effort was part of a large study to investigate how shallow water habitats in the Delta function and whether they provide good habitat for native fish species, including the Delta smelt.

Date published: June 26, 2020

CTD profiles and discrete water-column measurements collected off California and Oregon during NOAA cruise SH-18-12 (USGS field activity 2018-663-FA) from October to November 2018

Various water column variables, including CTD (Conductivity Temperature Depth) data were measured at selected depths from sites offshore of California and Oregon from October to November 2018 during NOAA cruise SH-18-12 on R/V Bell M. Shimada (USGS field activity 2018-663-FA).

Date published: June 25, 2020

Multibeam bathymetry, acoustic backscatter, and multichannel minisparker seismic-reflection data of USGS field activity 2016-666-FA collected in the Santa Barbara Basin in September and October of 2016

High-resolution multichannel minkisparker seismic-reflection profiles were collected by the USGS in September and October of 2016 from the northern portion of the Santa Barbara Basin offshore southern California. Data were collected aboard USGS R/V Parke Snavely and NOAA R/V Shearwater during field activity 2016-666-FA. Data were acquired to support USGS geologic hazards...

Date published: June 25, 2020

Multibeam bathymetry data of USGS field activity 2016-666-FA collected in the Santa Barbara Basin in September and October of 2016

These metadata describe bathymetry data collected during an October 2016 multibeam-echosounder survey of the northern portion of the Santa Barbara Channel, California. Data were collected and processed by the the U.S. Geological Survey (USGS), Pacific Coastal and Marine Science Center (PCMSC) with fieldwork activity number 2016-666-FA. The bathymetry data are provided as a GeoTIFF ima

Date published: June 25, 2020

Multichannel minisparker seismic-reflection data of USGS field activity 2016-666-FA collected in the Santa Barbara Basin in September and October of 2016

High-resolution multichannel minkisparker seismic-reflection (MCS) profiles were collected by the U.S. Geological Survey in September and October of 2016 from the northern portion of the Santa Barbara Basin offshore southern California. Data were collected aboard the USGS R/V Parke Snavely and NOAA R/V Shearwater during field activity 2016-666-FA using a SIG 2-mille minisparker and record

Date published: June 25, 2020

Acoustic-backscatter data of USGS field activity 2016-666-FA collected in the Santa Barbara Basin in September and October of 2016

These metadata describe acoustic-backscatter data collected during an October 2016 multibeam-echosounder survey of the northern portion of the Santa Barbara Channel, California. Data were collected and processed by the U.S. Geological Survey (USGS), Pacific Coastal and Marine Science Center (PCMSC) with fieldwork activity number 2016-666-FA. The acoustic-backscatter data are provided

Date published: June 25, 2020

Little Holland Tract and Wildlands Flux Study; Zooplankton, Phytoplankton, and Larval Fish Taxonomic Data, 2017-2018

This data set includes taxonomic data for zooplankton, larval fish, and phytoplankton sampled in Little Holland Tract and Liberty Island Conservation Bank, in the northern Sacramento-San Joaquin River Delta, California. Zooplankton and larval fish were collected with target specific trawl nets and phytoplankton was collected from water grabs. This data release includes all measured enviro

Date published: June 23, 2020

Global Geochemical Database for Critical Minerals in Archived Mine Samples

The Critical Minerals in Archived Mine Samples Database (CMDB) contains chemistry and geologic information for historic ore and ore-related rock samples from mineral deposits in the United States. In addition, the database contains samples from archetypal deposits from 27 other countries in North America, South America, Asia, Africa and Europe. Samples were obtained from archived ore

Date published: May 27, 2020

Bathymetry, topography and orthomosaic imagery for Whiskeytown Lake, northern California

Approximately 93% of the area within Whiskeytown National Recreation Area was burned extensively during the Carr Fire, including all of the landscape surrounding and draining into Whiskeytown Lake. The lake, a federally managed reservoir, therefore acted as a sediment trap for material eroded from hillslopes and streambeds in the aftermath of the Carr Fire. USGS measured ...

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

Filter Total Items: 416
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Year Published: 2019

κ0 and broadband site spectra in Southern California from source model-constrained inversion

Ground-motion modeling requires accurate representation of the earthquake source, path, and site. Site amplification is often modeled by VS30, the time-averaged shear-wave velocity of the top 30 meters of the Earth’s surface, though recent studies find that its ability to accurately predict site effects varies. Another measure of the site is κ0,...

Klimasewski, Alexis; Sahakian, Valerie J.; Baltay, Annemarie S.; Boatwright, John; Fletcher, Jon Peter; Baker, Lawrence

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Year Published: 2019

Santa Rosa's past and future earthquakes

Santa Rosa is no stranger to earthquakes. This northern California city was damaged several times in the late 19th and early 20th centuries by shaking from earthquakes, culminating in the devastating earthquake of 1906, whose rupture passed 20 miles to the west of the city on the San Andreas Fault. Then in 1969, Santa Rosa was again strongly...

Hecker, Suzanne; McPhee, Darcy K.; Langenheim, Victoria E.; Watt, Janet T.
Hecker, S., McPhee, D.K., Langenheim, V.E., and Watt, J.T., 2019, Santa Rosa's past and future earthquakes: U.S. Geological Survey Fact Sheet 2019–3035, 4 p., https://doi.org/10.3133/fs20193035.

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Year Published: 2019

Offshore shallow structure and sediment distribution, Punta Gorda to Point Arena, Northern California

This publication consists of two map sheets that display shallow geologic structure, along with sediment distribution and thickness, for an approximately 150-km-long offshore section of the northern California coast between Punta Gorda and Point Arena. Each map sheet includes three maps at scales of either 1:100,000 or 1:200,000, and together the...

Beeson, Jeffrey W.; Johnson, Samuel Y.
Beeson, J.W., and Johnson, S.Y., 2019, Offshore shallow structure and sediment distribution, Punta Gorda to Point Arena, northern California: U.S. Geological Survey Open-File Report 2019–1072, 2 sheets, scales 1:100,000 and 1:200,000, https://doi.org/10.3133/ofr20191072.

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Year Published: 2019

Airborne radiometric maps of Mountain Pass, California

Geophysical 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 encompasses Mountain Pass, host to one of the world’s largest rare earth element carbonatite deposits. The...

Ponce, David A.; Ponce, David A.; Denton, Kevin M.
Ponce, D.A., and Denton, K.M. (D.A. Ponce, ed.), 2019, Airborne radiometric maps of Mountain Pass, California: U.S. Geological Survey Scientific Investigations Map 3412–C, scale 1:62,500, https://doi.org/10.3133/sim3412C.

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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.

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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.

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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.

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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

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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

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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.

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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.

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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.

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June 11, 2020

Land Treatment Exploration Tool — Step 5: Select Search Parameters

This video describes Step 5 of the Land Treatment Exploration Tool. In Step 5 the user determines a distance or boundary to search for legacy Land Treatment Digital Library records. The user also indicates if the returned LTDL treatments are statistically evaluated against the planned treatment boundary using a Bray-Curtis Dissimilarity calculation.

These tutorial

June 11, 2020

Land Treatment Exploration Tool — Step 6: Compare the LTDL Treatments

This video describes Step 6 of the Land Treatment Exploration Tool. In Step 6 the user filters through the returned list of legacy LTDL treatments to identify records that contain useful information or context for the current planned treatment boundary. Selected treatments are added to the developing report and subsequent exported Site Characterization PDFs.  

These

Illustration of the seafloor showing depth and locations of surveys.
June 5, 2020

Figure 5 offshore Morro Bay seafloor detail

Colored shaded-relief bathymetry including pockmarks offshore Morro Bay, California. Map generated from AUV-based multibeam bathymetry data collected by MBARI.

Figure 1: EXPRESS surveys, dives, and sampling locations
Figure 2: 

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Illustration of a coastal area with lines, dots, and boxes drawn on it to show where data was collected.
June 5, 2020

EXPRESS surveys, dives, and sampling locations

The west coast of the United States showing locations of EXPRESS ship-based multibeam surveys, ROV dives, AUV dives, and sediment samples. Red boxes show locations of close-up views of multibeam bathymetry in Figures 2 and 3.

Figure 1: EXPRESS surveys, dives, and sampling

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Illustration of the seafloor that shows depth, and where data was collected.
June 5, 2020

Trinidad submarine canyon bathymetry

Colored, shaded-relief bathymetry of Trinidad Submarine Canyon northwest of Humboldt Bay in northern California. Area is in the vicinity of a potential offshore renewable energy development. See larger map for location.

Figure 1: 

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Illustration of the seafloor off a coastal area, with lines and dots to show where data was collected.
June 5, 2020

Offshore central California bathymetry

Colored, shaded-relief bathymetry offshore central California. Data supported management of National Marine Sanctuaries and prospective renewable energy decisions. Black ovals are locations of AUV-based multibeam surveys. Close-up views of two AUV surveys are shown in Figures 4 and 5.

Figure 1: 

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Illustration of the seafloor showing depth and locations of surveys.
June 5, 2020

Figure 4 offshore Morro Bay seafloor detail

Colored shaded-relief bathymetry including submarine channels and pockmarks offshore Morro Bay, California. Map generated from AUV-based multibeam bathymetry data collected by MBARI both prior to and as a part of EXPRESS.

Figure 1: EXPRESS surveys, dives, and sampling locations

...
May 21, 2020

Count the bats -- how do your skills compare to a bat biologist's?

Do you have what it takes to be a bat biologist? USGS bat researchers are counting Townsend’s big eared bats to monitor how their populations are doing. Watch the video to try your hand at a bat count and see how your skills compare to a USGS scientist! You don’t need sound to count the bats—but if you turn your sound on you’ll be able to hear the bats’ echolocation calls

A man stands on the bow of a small aluminum boat wearing bib waders, a personal floatation device, and a mask.
May 4, 2020

The new face of fieldwork

Marine technician Dan Powers, from the Pacific Coastal and Marine Science Center's Marine Facility (PCMSC MarFac), wears all the required personal protective equipment: bib waders, personal floatation device, and mask. He and MarFac engineering technician Pete Dal Ferro went out on Alviso Slough to retrieve and clean current meters that are secured to metal frames. The

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A man navigates a personal watercraft slowly out of a harbor along a jetty.
March 12, 2020

Personal watercraft equipped with sonar and GPS

A USGS scientist navigates a personal watercraft (PWC) slowly through Elkhorn Slough. The PWC is equipped with an echosounder and GPS, to record accurate depth and location. This mapping effort is part of recurring surveys in the Monterey Bay area. Data from these surveys help the USGS understand how sand moves around the Bay, how the beaches, inlets, harbors, and other

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A person navigates a personal watercraft in the nearshore with coastal bluffs in the background.
March 10, 2020

Collecting nearshore bathymetry data off Rio del Mar

A USGS scientist navigates a personal watercraft equipped with sonar and GPS to collect depth information (bathymetry) of the nearshore. This mapping effort is part of recurring surveys in the Monterey Bay area. Data from these surveys help the USGS understand how sand moves around the Bay, how the beaches, inlets, harbors, and other coastal features change with storms and

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A young woman walks along the sand wearing a backpack with light equipment in it.
March 9, 2020

Collecting beach profile data with GPS

A USGS scientist walks along Santa Cruz Main Beach at the edge of the San Lorenzo River in Santa Cruz, California, wearing a backpack with GPS equipment. She is collecting elevation data that will be used to create a topographic map of the beach. This mapping effort is part of recurring surveys in the Monterey Bay area. Data from these surveys help the USGS understand how

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Shallow Structure and Geomorphology along the Offshore Northern San Andreas Fault, Tomales Point to Fort Ross, California
August 3, 2020

Study of New Offshore Fault Mapping Related to the 1906 San Francisco Earthquake:  In 2019, for the first time ever, scientists comprehensively mapped a previously overlooked offshore section of the San Andreas Fault system which may provide insight on how the fault could rupture in the future.

Dragonfly larvae being held in an open hand
July 21, 2020

A team of federal, academic, and NGO researchers conducted a national-scale assessment of mercury bioaccumulation in aquatic ecosystems using dragonfly larvae as biosentinels.

Illustration model of the Cascadia Subduction Zone
June 22, 2020

The geologic research and mapping in the offshore areas is foundational to understanding how to manage resources and improve public safety in subduction zone areas.

Underwater photo of a rocky outcrop with fish.
June 22, 2020

As state and national interest in offshore renewable energy development and substantial commercial and recreational fishing activities grows, managing offshore habitats becomes increasingly challenging. In response, USGS and BOEM have joined NOAA and several non-Federal partners to initiate EXpanding Pacific Research and Exploration of Submerged Systems (EXPRESS), a multiyear campaign.

map of Los Angeles area with different gradational colors
June 1, 2020

One USGS scientist has sorted through the challenges, the claims, and the data to determine what the possibilities and limitations really are for EEW, and the results may surprise you.

Read the new Science for Everyone article: The Blind Zone of Earthquake Early Warning

Animated GIF of Clear Lake volcanic field monitoring extents, cycling between two maps with polygons enclosing earthquake zones.
May 13, 2020

If you've noticed any changes to the earthquake counts released in CalVO's weekly updates, don't worry - some behind-the-scenes improvements to our monitoring system have been implemented which allow us to focus on unrest specifically related to our volcanoes and volcanic regions.

Southern Rincon Valley in Doña Ana County, New Mexico
April 22, 2020

Changes in population, agricultural practices, and climate are increasing demands on available water resources, particularly groundwater, in the southwest.

Hydrologist Michael Land is shown sampling a public supply well in the upper Santa Ana watershed.
April 1, 2020

In California, groundwater is a major source for drinking and other uses. Identifying where groundwater quality is getting better or worse is essential for managing groundwater resources.

Photo of hydrologist Steve Ingebritsen (2015)
March 31, 2020

Dr. Steve Ingebritsen retires this week from the USGS after a stellar career spanning four decades.

California Volcano Observatory emblem
March 24, 2020

California Volcano Observatory monitoring activities continue as normal; scientists and staff following precautionary safety measures.

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