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: 421
Date published: October 30, 2017
Status: Active

Population Biology and Behavior of Sea Otters

WERC's sea otter researchers are developing and utilizing a variety of methodological and analytical tools to understand the causes of biological and ecological trends in sea otter populations, and to predict the ecological consequences of management practices on these populations and their ecosystems.

Date published: October 30, 2017
Status: Active

Waterfowl Ecology in California and the Pacific Flyway

The Suisun Marsh and Central Valley in California offer some of the world’s most important wetland habitats for waterfowl in the Pacific Flyway. Mike Casazza and USGS WERC biologists are providing the science to support and evaluate waterfowl populations and habitat management in North America.

Contacts: Michael Casazza
Date published: October 30, 2017
Status: Active

Pacific Nearshore Project

Sea otters are crucial indicators of the health of our nearshore waters and coastal resources, from kelp forests to fisheries. What clues does the sea otter's decline hold for our knowledge of ecosystem and global change? WERC's sea otter team and U.S. and Canadian researchers have teamed together to investigate. 

Relevance to USGS Missions:

This research project has direct...

Date published: October 30, 2017
Status: Active

Modeling Sea-Level Rise in San Francisco Bay Estuary

With sea level rise, how will the coastal habitats of the San Francisco Bay Estuary change over the next 100 years? Mapping and modeling studies by Dr. Karen Thorne, WERC scientists, and partners have produced scenarios for this important coastal ecosystem.

Date published: October 30, 2017
Status: Active

Ecology and Population Dynamics of Ridgway's Rails along the West Coast of the U.S.

The Ridgway’s rail is a federal and state listed endangered species that occurs in wetlands along the Pacific Coast and from the Lower Colorado River drainage to southern Baja California. Three subspecies of Ridgway’s rail are found within the United States: the California Ridgway’s Rail, Yuma Ridgway’s rail, and Light-footed Ridgway’s rail.  All three subspecies have declined since 1900 as a...

Contacts: Michael Casazza
Date published: October 30, 2017
Status: Active

Wildland Fire Science in Forests and Deserts

Fuel conditions and fire regimes in western forests and deserts have been altered due to past land management, biological invasions, and recent extreme weather events and climate shifts. These changes have created extreme fire risk to local and regional communities, threatening their economic health related to wildland recreation, forest production, livestock operations, and other uses of...

Contacts: Matthew Brooks
Date published: October 30, 2017
Status: Active

Aridlands Disturbances and Restoration Ecology

Desert landscapes are rapidly changing due to increases in invasive plant species, frequency of wildfires, urban and energy development, recreational use, military training, and climate variation. Dr. Todd Esque, USGS researchers, and collaborators are working together to investigate these changes and provide managers with key information that can be used to manage natural resources more...

Contacts: Todd Esque
Date published: October 30, 2017
Status: Active

Desert Tortoise Ecology, Health, Habitat, and Conservation Biology

The desert tortoise is listed as “threatened” under the Endangered Species Act. USGS WERC scientists, along with project partners have been conducting long-term analyses on how changes in the southwestern deserts of the United States can affect desert tortoise populations. Dr. Todd Esque and his team are investigating how habitat disturbances and restoration projects influence tortoise...

Contacts: Todd Esque
Date published: October 30, 2017
Status: Active

Breeding and Wintering Ecology of Waterfowl

Western U.S. wetlands provide critical habitat for wintering and breeding waterfowl in California. WERC's Dr. Josh Ackerman is working toward collecting data to understand factors influencing duck nest success, to improve and restore breeding habitat for resident duck populations in California, and understand composition of predator communities. To learn more about how USGS WERC is...

Contacts: Josh T Ackerman
Date published: October 30, 2017
Status: Active

Coastal Ecosystem Response to Sea-level Rise

USGS WERC’s Dr. Karen Thorne, her team of reseachers, and her partners are currently taking a local site network approach to describe current and future conditions and projected responses of coastal ecosystems to sea-level rise and other stressors. The Coastal Ecosystem Response to Climate Change (CERCC) program’s goal is to understand how ecosystems vary in their ability to keep up with sea-...

Date published: September 20, 2017
Status: Active

Land Treatment Digital Library

The LTDL was created by the U.S. Geological Survey (USGS) to catalog information about land treatments on Federal lands in the western United States for all interested parties. The flexible framework of the library allows for the storage of a wide variety of data in different formats. The LTDL currently stores previously established land treatments or what often are called legacy data. The...

Date published: August 5, 2017
Status: Active

RestoreNet: Distributed Field Trial Network for Dryland Restoration

U.S. Geological Survey (USGS) researchers and land managers are co-producing a network of restoration field trial sites on DOI and surrounding lands in the southwestern U.S. The network systematically tests restoration treatments across a broad range of landscape, soil, and climate conditions. Each site in the network is used to test suitable seed mixes and treatments that promote plant...

Contacts: Seth Munson, Molly McCormick, Katie Laushman, Rebecca Mann, Mike Duniway, Ph.D., Brad Butterfield, Elise Gornish, Loralee Larios, Akasha Faist, Helen Rowe, Christopher Lortie, Caroline A. Havrilla
Filter Total Items: 588
Date published: November 30, 2018

Downloadable Data for Sonoma-Livermore Basin Oil and Gas Assessments

GIS Data Sonoma-Livermore Basin Oil and Gas Assessments 

Date published: November 30, 2018

Downloadable Data for Northern Coastal Basin Oil and Gas Assessments

Northern Coastal Basin Oil and Gas Assessments

Date published: November 29, 2018

Downloadable Data for San Joaquin Basin Oil and Gas Assessments

Downloadable Data for San Joaquin Basin Oil and Gas Assessments

Date published: November 29, 2018

Downloadable Data for Sacramento Basin Oil and Gas Assessments

Downloadable Data for Sacramento Basin Oil and Gas Assessments

Date published: November 8, 2018

2010 Estimated California Water Use

Withdrawal estimates for each category represent the total amount of water removed from the water source, regardless of how much of that total is consumptively used. In most cases, some fraction of the total withdrawal will be returned to the same or a different water source after use and is available for other withdrawals.

Date published: October 29, 2018

California Seafloor Mapping Program progress

Table showing California Seafloor Mapping Program map block mapping progress by block number, as of April 2018.

Date published: October 25, 2018

Beach topography and nearshore bathymetry of northern Monterey Bay, California

This data release presents beach topography and nearshore bathymetry data from repeated surveys in northern Monterey Bay, California to document changes in shoreline position and coastal morphology as they relate to episodic (storms), seasonal, and interannual and longer processes. Since October 2014, semi-annual surveys have been performed in late summer (September or October...

Date published: October 22, 2018

Grain size, mineralogic, and trace-element data from field samples near Hinkley, California

This data release is part of a study examining the occurrence of chromium and natural and anthropogenic hexavalent Chromium, Cr(VI) in groundwater. Data will be used to estimate naturally-occurring background Cr(VI) concentrations upgradient, near the plume margins, and downgradient from a mapped Cr(VI) contamination plume near Hinkley, CA (Izbicki and Groover, 2016).

Date published: October 5, 2018

Bathymetry, acoustic-backscatter, and time-series datasets collected between 2014 and 2016 of a field of crescent-shaped rippled scour depressions in northern Monterey Bay, California

Between 11/14-6/16 USGS PCMSC conducted 8 repeat, high-resolution bathymetry and acoustic-backscatter surveys of a small patch of seafloor offshore Santa Cruz in northern Monterey Bay, California. We also collected oceanographic time-series data over the same two-year period. This data release provides the eight bathymetry and acoustic-backscatter datasets, the time-series data, and FGDC...

Date published: October 4, 2018

Electrical Resistivity Tomography Data at Fort Irwin National Training Center, San Bernardino County, California, 2015 and 2017

The U.S. Army Fort Irwin National Training Center (NTC), approximately 35 mi north-northeast of Barstow, California, covers approximately 1,177 square miles, and is comprised of ten groundwater basins, three of which have been subdivided into subbasins on the basis of additional hydrologic testing. Since the early 1990s, the U.S. Geological Survey (USGS) has been studying water resources...

Date published: September 24, 2018

Bathymetry and acoustic backscatter data collected in 2007 from the San Miguel Passage in the Channel Islands, California

Bathymetry and acoustic backscatter data were collected in the San Miguel Passage, Channel Islands, California in August 2007. Data collection was conducted aboard the ship R/V Shearwater as part of the USGS research cruise S-2-07-SC. The San Miguel Passage is within the Channel Islands National Marine Sanctuary, and is the body of water between the two western-most islands of the...

Date published: August 28, 2018

USGS Domestic Continuous (Unconventional) Oil & Gas Assessments, 2000-Present

Interactively explore assessment summary information for continuous (unconventional) assessments conducted at the USGS from 2000-2018. The assessment results data used to generate this visualization can be downloaded here in Excel Format.  These data represent all assessment results...

Filter Total Items: 485
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Year Published: 2008

Environmental factors affecting mercury in Camp Far West Reservoir, California, 2001-03

This report documents water quality in Camp Far West Reservoir from October 2001 through August 2003. The reservoir, located at approximately 300 feet above sea level in the foothills of the northwestern Sierra Nevada, California, is a monomictic lake characterized by extreme drawdown in the late summer and fall. Thermal stratification in summer...

Alpers, Charles N.; Stewart, A. Robin; Saiki, Michael K.; Marvin-DiPasquale, Mark C.; Topping, Brent R.; Rider, Kelly M.; Gallanthine, Steven K.; Kester, Cynthia A.; Rye, Robert O.; Antweiler, Ronald C.; De Wild, John F.
Environmental Factors Affecting Mercury in Camp Far West Reservoir, California, 2001-03; 2008; SIR; 2006-5008; Alpers, Charles N.; Stewart, A. Robin; Saiki, Michael K.; Marvin-DiPasquale, Mark C.; Topping, Brent R.; Rider, Kelly M.; Gallanthine, Steven K.; Kester, Cynthia A.; Rye, Robert O.; Antweiler, Ronald C.; De Wild, John F.

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Year Published: 2008

Using Logistic Regression to Predict the Probability of Debris Flows in Areas Burned by Wildfires, Southern California, 2003-2006

Logistic regression was used to develop statistical models that can be used to predict the probability of debris flows in areas recently burned by wildfires by using data from 14 wildfires that burned in southern California during 2003-2006. Twenty-eight independent variables describing the basin morphology, burn severity, rainfall, and soil...

Rupert, Michael G.; Cannon, Susan H.; Gartner, Joseph E.; Michael, John A.; Helsel, Dennis R.
Using Logistic Regression to Predict the Probability of Debris Flows in Areas Burned by Wildfires, Southern California, 2003-2006; 2008; OFR; 2008-1370; Rupert, Michael G.; Cannon, Susan H.; Gartner, Joseph E.; Michael, John A.; Helsel, Dennis R.

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Year Published: 2008

Sediment Deposition, Erosion, and Bathymetric Change in Central San Francisco Bay: 1855-1979

Central San Francisco Bay is the hub of a dynamic estuarine system connecting the San Joaquin and Sacramento River Deltas, Suisun Bay, and San Pablo Bay to the Pacific Ocean and South San Francisco Bay. To understand the role that Central San Francisco Bay plays in sediment transport throughout the system, it is necessary to first determine...

Fregoso, Theresa A.; Foxgrover, Amy C.; Jaffe, Bruce E.
Sediment Deposition, Erosion, and Bathymetric Change in Central San Francisco Bay: 1855-1979; 2008; OFR; 2008-1312; Fregoso, Theresa A.; Foxgrover, Amy C.; Jaffe, Bruce E.

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Year Published: 2008

Survival and migration behavior of juvenile coho salmon in the Klamath River relative to discharge at Iron Gate Dam, Northern California, 2007

This report describes a study of survival and migration behavior of juvenile coho salmon in the Klamath River relative to discharge at Iron Gate Dam in 2006. This was the second year of a multi-year study with the goal of determining the effects of discharge at Iron Gate Dam on survival of juvenile coho salmon downstream. The study was a...

Beeman, John W.; Stutzer, Greg; Juhnke, Steve; Hetrick, Nicholas
Survival and Migration Behavior of Juvenile Coho Salmon in the Klamath River Relative to Discharge at Iron Gate Dam, Northern California, 2007; 2008; OFR; 2008-1332; Beeman, John W.; Juhnke, Steve; Stutzer, Greg; Hetrick, Nicholas

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Year Published: 2008

Year 3 Summary Report: Baseline Selenium Monitoring of Agricultural Drains Operated by the Imperial Irrigation District in the Salton Sea Basin

This report summarizes findings from the third year of a 4-year-long field investigation to document selected baseline environmental conditions in 29 agricultural drains and ponds operated by the Imperial Irrigation District along the southern border of the Salton Sea. Routine water quality and fish species were measured at roughly quarterly...

Saiki, Michael K.; Martin, Barbara A.; May, Thomas W.
Year 3 Summary Report: Baseline Selenium Monitoring of Agricultural Drains Operated by the Imperial Irrigation District in the Salton Sea Basin; 2008; OFR; 2008-1271; Saiki, Michael K.; Martin, Barbara A.; May, Thomas W.

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Year Published: 2008

Liquefaction hazard maps for three earthquake scenarios for the communities of San Jose, Campbell, Cupertino, Los Altos, Los Gatos, Milpitas, Mountain View, Palo Alto, Santa Clara, Saratoga, and Sunnyvale, Northern Santa Clara County, California

Maps showing the probability of surface manifestations of liquefaction in the northern Santa Clara Valley were prepared with liquefaction probability curves. The area includes the communities of San Jose, Campbell, Cupertino, Los Altos, Los Gatos Milpitas, Mountain View, Palo Alto, Santa Clara, Saratoga, and Sunnyvale. The probability curves were...

Holzer, Thomas L.; Noce, Thomas E.; Bennett, Michael J.
Liquefaction Hazard Maps for Three Earthquake Scenarios for the Communities of San Jose, Campbell, Cupertino, Los Altos, Los Gatos, Milpitas, Mountain View, Palo Alto, Santa Clara, Saratoga, and Sunnyvale, Northern Santa Clara County, California; 2008; OFR; 2008-1270; Holzer, Thomas L.; Noce, Thomas E.; Bennett, Michael J.

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Year Published: 2008

Historical seismicity in the South San Francisco Bay Region

Locations (intensity centers) and moment magnitude M for 24 earthquakes (1858-1911) in the southern San Francisco Bay area are estimated from Modified Mercalli intensity (MMI) assignments. The uncertainties in location and M are generally large because there are few MMI assignments available. Preferred locations are selected to be consistent with...

Bakun, William H.
Historical Seismicity in the South San Francisco Bay Region; 2008; OFR; 2008-1151; Bakun, William H.

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Year Published: 2008

Structure of the San Bernardino Basin along two seismic transects: Rialto-Colton Fault to the San Andreas Fault and along the I-215 Freeway (I-10 to SR30)

In this report, we present seismic data and acquisition parameters for two seismic profiles acquired in the San Bernardino, California area in May and October 2003. We refer to these seismic profiles as the San Bernardino Regional (SBR) and San Bernardino High-Resolution (SBHR) seismic profiles. We present both un-interpreted and interpreted...

Catchings, R. D.; Rymer, M. J.; Goldman, M. R.; Gandhok, G.; Steedman, C.E.
Structure of the San Bernardino Basin Along Two Seismic Transects: Rialto-Colton Fault to the San Andreas Fault and Along the I-215 Freeway (I-10 to SR30); 2008; OFR; 2008-1197; Catchings, R. D.; Rymer, M. J.; Goldman, M. R.; Gandhok, G.; Steedman, C. E.

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Year Published: 2008

Total selenium and selenium species in irrigation drain inflows to the Salton Sea, California, October 2007 and January 2008

This report presents the results for two sampling periods (October 2007 and January 2008) during a 4-year monitoring program to characterize selenium concentrations in selected irrigation drains flowing into the Salton Sea, California. Total selenium, selenium species (selenite, selenate, organoselenium), and total suspended solids were determined...

May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.
Total Selenium and Selenium Species in Irrigation Drain Inflows to the Salton Sea, California, October 2007 and January 2008; 2008; OFR; 2008-1178; May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.

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Year Published: 2008

The ShakeOut Earthquake Scenario— A story that southern Californians are writing

The question is not if but when southern California will be hit by a major earthquake - one so damaging that it will permanently change lives and livelihoods in the region. How severe the changes will be depends on the actions that individuals, schools, businesses, organizations, communities, and governments take to get ready. To help prepare for...

Perry, Suzanne; Cox, Dale; Jones, Lucile; Bernknopf, Richard; Goltz, James; Hudnut, Kenneth; Mileti, Dennis; Ponti, Daniel; Porter, Keith; Reichle, Michael; Seligson, Hope; Shoaf, Kimberley; Treiman, Jerry; Wein, Anne
The ShakeOut Earthquake Scenario - A Story That Southern Californians Are Writing; 2008; CIR; 1324; Perry, Suzanne; Cox, Dale; Jones, Lucile; Bernknopf, Richard; Goltz, James; Hudnut, Kenneth; Mileti, Dennis; Ponti, Daniel; Porter, Keith; Reichle, Michael; Seligson, Hope; Shoaf, Kimberley; Treiman, Jerry; Wein, Anne

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Year Published: 2008

The ShakeOut Scenario

This is the initial publication of the results of a cooperative project to examine the implications of a major earthquake in southern California. The study comprised eight counties: Imperial, Kern, Los Angeles, Orange, Riverside, San Bernardino, San Diego, and Ventura. Its results will be used as the basis of an emergency response and preparedness...

Jones, Lucile M.; Bernknopf, Richard; Cox, Dale; Goltz, James; Hudnut, Kenneth; Mileti, Dennis; Perry, Suzanne; Ponti, Daniel; Porter, Keith; Reichle, Michael; Seligson, Hope; Shoaf, Kimberley; Treiman, Jerry; Wein, Anne
The ShakeOut Scenario; 2008; OFR; 2008-1150; Jones, Lucile M.; Bernknopf, Richard; Cox, Dale; Goltz, James; Hudnut, Kenneth; Mileti, Dennis; Perry, Suzanne; Ponti, Daniel; Porter, Keith; Reichle, Michael; Seligson, Hope; Shoaf, Kimberley; Treiman, Jerry; Wein, Anne

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Year Published: 2008

Leachate Geochemical Results for Ash and Burned Soil Samples from the October 2007 Southern California Wildfires

This report is the second release of leachate geochemical data included as part of a multidisciplinary study of ash and burned soil samples from the October 2007 wildfires in southern California. Geochemical data for the first set of samples were released in an Open-File Report (Plumlee and others, 2007). This study is a continuation of that work...

Hageman, Philip L.; Plumlee, Geoffrey S.; Martin, Deborah A.; Hoefen, Todd M.; Meeker, Gregory P.; Adams, Monique; Lamothe, Paul J.; Anthony, Michael W.
Leachate Geochemical Results for Ash and Burned Soil Samples from the October 2007 Southern California Wildfires; 2008; OFR; 2008-1139; Hageman, Philip L.; Plumlee, Geoffrey S.; Martin, Deborah A.; Hoefen, Todd M.; Meeker, Gregory P.; Adams, Monique; Lamothe, Paul J.; Anthony, Michael W.

Filter Total Items: 1,119
April 20, 2018

MODIS and VIIRS Observe Snowpack in the Sierra Nevada Mountain Range

The Moderate Resolution Imaging Spectroradiometer (MODIS) sensor is located onboard NASA’s Terra and Aqua satellites. The Visible Infrared Imaging Radiometer Suite (VIIRS) sensor is located onboard the joint NASA/NOAA Suomi National Polar-Orbiting Partnership (S-NPP) and data products created by NASA provide a continuation of the MODIS data heritage. These data are crucial

View from a rooftop looking down into a cove with gentle ocean waves, coastal bluffs, surfers and anchored boat in distance.
April 19, 2018

Cowells Beach Snapshot

Snapshot, or first frame of from a 10-minute video taken on April 19, 2018, in Santa Cruz, California. View is from atop a hotel looking down on Cowells Beach, a popular surf spot. Researchers at the USGS are using these and other video images to improve understanding and computer modeling of beach processes, especially those that change the coast. 

...
April 18, 2018

HayWired Scenario - Movie

The HayWired earthquake scenario, led by the U.S. Geological Survey (USGS), anticipates the impacts of a hypothetical magnitude-7.0 earthquake on the Hayward Fault. The fault is along the east side of California’s San Francisco Bay and is among the most active and dangerous in the United States, because it runs through a densely urbanized and interconnected region. 

Gas chromatograph-mass spectrometer (GCMS) used for pesticide analysis
April 4, 2018

Gas chromatograph-mass spectrometer (GCMS) used for pesticide analysis

Organic Chemistry Research Laboratory — Sacramento, California. Gas chromatograph-mass spectrometer - GCMS

View from the sky of a marsh labeled with sample locations.
April 2, 2018

Little Holland Tract and Liberty Island sample locations, 2014-2017

Sediment sampling locations in the Sacramento-San Joaquin Delta, California near Little Holland Tract and Liberty Island, 2014 to 2017

Map of California showing the sections of the coast where the USGS has generated computer models of storm impacts.
April 2, 2018

CoSMoS Implementation versions

The Coastal Storm Modeling System (CoSMoS) makes detailed predictions (meter-scale) over large geographic scales (100s of kilometers) of storm-induced coastal flooding and erosion for both current and future SLR scenarios, as well as long-term shoreline change and cliff retreat.  Resulting projections for future climate scenarios (sea-level rise and storms) provide

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Comparison maps indicating short or long times available for earthquake shaking arrival times
March 31, 2018

Earthquake Alerts: Early and Often? Or Possibly Late?

The choice when issuing earthquake warnings is to: 1) issue alerts for weak shaking and potentially provide long warning times, but risk sending alerts for the many events that do not go on to produce damaging ground shaking, or 2) issue alerts only when ground shaking is expected to be damaging, with the tradeoff that the alert will be sent much later, reducing the

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A coastline with trees on the beach berm on left, two people looking out at two jet skis, waves are gentle, sun is gleaming.
March 28, 2018

Nearshore survey of San Ysidro Creek

Two USGS scientists operate personal watercraft equipped with sonar and GPS along the beachfront off San Ysidro Creek, near Fernald Point in Montecito, California. They will use the data collected to create bathymetric (depth) maps. Collecting these data on a seasonal basis over many years provides a detailed picture of how the coastline reacts to changes in waves and

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Two women stand together smiling on a boat wearing life jackets and sun hats with other safety gear.
March 27, 2018

Fieldwork in the Delta

Shruti Khanna (left, California Department of Fish and Wildlife) and Judy Drexler (USGS California Water Science Center) on the USGS Pacific Coastal and Marine Science Center’s research vessel Parke Snavely during fieldwork in the Sacramento-San Joaquin River Delta.

An object of two circular pieces of mixed materials are partially covered with mud and plant debris.
March 27, 2018

Instrument package for river data collection

Patches of dark sand cling to an instrument package that collected data for approximately two weeks at the Mokelumne River site—evidence that currents at the site were strong enough to carry sand, which is heavier than mud, probably during elevated river flows following two storms in the watershed.

A woman and a man stand on the stern of a boat wearing safety gear, man is pressing on a piece of equipment.
March 19, 2018

Gomex sediment corer preparation

Dan Powers (USGS PCMSC) and Rachel Marcuson (USGS PCMSC) prepare to deploy a Gomex sediment corer from the R/V Snavely in the Mokulumne River near confluence of San Joaquin River in the Sacramento-San Joaquin Delta, CA.

Filter Total Items: 992
Historical photo of a flood on Willamette River in Oregon from 1964
December 11, 2014

The Christmas flood of 1964 encompassed about 200,000 square miles, or roughly the size of France, resulted in 47 deaths, left thousands homeless and caused more than $540 million ($3.9 billion today) worth of damage.

Map showing drought coverage of California
December 8, 2014

A newly released interactive California Drought visualization website aims to provide the public with atlas-like, state-wide coverage of the drought and a timeline of its impacts on water resources.

Earthquake swarm near Lassen Volcanic Center Nov 6 to Nov 12, 2014...
November 12, 2014

CalVO is tracking an earthquake swarm that began on November 9 located at the Tehama County-Plumas County border within Lassen National Forest.

Seismicity in the Long Valley Volcanic Region between 2004 and 2014...
October 31, 2014

A cataclysmic eruption of 600 km3 of rhyolite magma (Bishop Tuff) about 760,000 years ago resulted in the collapse of the partially evacuated magma chamber to form the present 17 by 32 km (10 by 20 mi) Long Valley Caldera.

thumbnail image of flyer for Wolf and Elk Diseases in Yellowstone presentation
October 30, 2014

What can wildlife diseases tell us about the emergence of human pandemics? 

Image: Coastal Survey Vessel in Use at Santa Cruz, California
October 20, 2014

During the week of Oct 20 - 24 scientists from the U.S. Geological Survey will be working along the coastline from Santa Cruz to Moss Landing. Either by all-terrain vehicle, personal watercraft, or on foot, they will be surveying local beaches and the nearby ocean bottom to compile a three-dimensional map of how beaches change in northern Monterey Bay.

USGS
October 14, 2014

The Downtown Association of Santa Cruz will host a 25th anniversary commemoration of the Loma Prieta Earthquake.

WERC Sierra Nevadas
October 13, 2014

The USGS California Volcano Observatory (CalVO) is tracking an earthquake swarm in the Sierra Nevada range south of Long Valley Caldera, about 8 miles SW of Toms Place and 15 miles SE of the town of Mammoth Lakes.

Long Valley Caldera Earthquakes greater than M1.0 from 09/22 to 09/...
September 28, 2014

Over the past 42 hours, the earthquake swarm in California's Long Valley Caldera, which began last Friday (see September 26 post), has gradually diminished in terms of numbers of earthquakes and in earthquake magnitude.

Long Valley Caldera Earthquakes greater than M1.0 from 09/22 to 09/...
September 26, 2014

We have been closely tracking an earthquake swarm in California's Long Valley Caldera, which started yesterday at around 4AM PDT (September 25, 2014).

Mount Shasta looming over the town of Weed in the evening....
September 25, 2014

On the afternoon of September 20, a large volume of water surged down Mount Shasta's south flank into Mud Creek, entraining debris and inundating the drainage and roads near McCloud, California.