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: March 27, 2018
Status: Active

Assessing Deposit Build-up in Corte Madera Flood Control Channel

The Corte Madera Flood Control Channel was designed to prevent waters from overflowing Corte Madera Creek in a highly populated area of Marin County. Since the channel was last dredged in 1990 approximately 5,400 cubic feet of sediment has accumulated. The accumulation of sediment is of concern because the sediment may reduce the effectiveness of the channel, posing a flooding threat to...

Contacts: Daniel Livsey
Date published: March 21, 2018
Status: Active

Studying Threatened Fish Species in Clear Lake, CA

A fish species known as the Clear Lake Hitch, presently listed as threatened under the California Endangered Species Act, is now being considered by the U.S. Fish and Wildlife Service for placement on its endangered species list. The hitch population, which once flourished in great abundance, has been decimated by loss of spawning habitat, nursery areas, and the encroachment of non-native...

Date published: March 20, 2018
Status: Active

Tsunamis

The 2004 Indian Ocean, 2010 Chilean, and 2011 Tohoku disasters have shown how tsunamis are significant threats to coastal communities. To help U.S. coastal communities prepare for future tsunamis, the Hazards Vulnerability Team completed projects related to population exposure and sensitivity, pedestrian evacuation modeling, and vertical-evacuation decision support.

A recent article of...

Date published: March 16, 2018
Status: Active

Chiricahua Mountains - Reduction of Channel Gradients

Drainages in the Chiricahua Mountains are impacted by large rain events that cause gullying effects in the headwaters, overflow at road crossings, flooding of campgrounds, and overwhelming sediment loads at outlets (Chiricahua National Monument). Monsoon rains following recent fires cause severe flooding in most drainages and debris flows in many others (Youberg et al. 2013). Watershed...

Date published: March 14, 2018
Status: Active

Babocomari - Managed Aquifer Recharge

We are working to investigate the most cost-efficient way to recharge the Sierra Vista sub-basin aquifer using rainwater harvesting in the tributaries of the San Pedro River using low-technology methods. Research is being conducted on the Babacomari Ranch, property of the Brophy family. The Walton Family Foundation (WFF) is supporting our research with partners, Borderlands Restoration (BR), ...

Date published: March 14, 2018
Status: Active

Aridland Water Harvesting Study

Most of western North America has been severely grazed by cattle, causing grasslands to deteriorate and desert scrub expansion. Climate in arid and semi-arid regions is often typified by short, intense rainfall events which contribute to short-term flooding and erosion. Associated arroyo cutting occurs when ephemeral creek beds are carved into the floodplain when erratic overland flow occurs;...

Date published: January 18, 2018
Status: Active

Forecasting Coastal Change

This project focuses on understanding the magnitude and variability of extreme storm impacts on sandy beaches. The overall objective is to improve real-time and scenario-based predictions of coastal change to support management of coastal infrastructure, resources, and safety. 

Contacts: Kara Doran
Date published: January 18, 2018
Status: Active

National Assessment of Coastal Vulnerability to Sea Level Rise

The original national coastal vulnerability index (CVI) assessment was motivated by expected accelerated sea-level rise (SLR) and the uncertainty in the response of the coastline to SLR. This research was conducted between 1999 and 2001, and is currently being updated using new data sources and methodology. This original study was part of the ...

Date published: January 18, 2018
Status: Active

Long-Term Coastal Change

Goals of this task include developing and improving coastal-change assessments and supporting long-term planning and decision making to ensure sustainable coastal economies, infrastructure, and ecosystems.

Date published: December 7, 2017
Status: Active

The Mud Creek landslide on California’s Big Sur coast

On May 20, 2017, the steep slopes at Mud Creek on California’s Big Sur coast, about 140 miles south of San Francisco, suffered a catastrophic collapse. USGS Scientists from the Pacific Coastal and Marine and the Geology, Minerals, Energy, and Geophysics Science Centers are monitoring this section of the coastline, in collaboration with the California Department of Transportation.

Date published: October 30, 2017
Status: Active

Ecology of Infectious Diseases

The public is most familiar with parasites' role in spreading infectious diseases to people and domestic animals. In tropical developing countries, malaria, schistosomiasis, and other infectious diseases cause significant human suffering. While most related studies focus on treating patients, Dr. Kevin Lafferty is studying how ecology of the local environment affects transmission of infectious...

Contacts: Kevin Lafferty
Filter Total Items: 583
Date published: December 21, 2018

California Flood Activity Alerts

USGS Project Alert Notices RSS feed includes response summaries of USGS streamgaging network activity during storm events in California. These Notices are produced by USGS Streamgaging Programs nationally and can be found on the USGS Current Floods Website.

Date published: December 19, 2018

Drought & Groundwater in California

Long-term groundwater-level data are fundamental to the resolution of problems dealing with groundwater availability and sustainability. Significant periods of time typically are required to collect water-level data needed to assess the effects of climate variability, to monitor the effects of regional aquifer development, or to obtain data sufficient for analysis of water-level trends.

Date published: December 19, 2018

Runoff Estimates for California

Streams, rivers, lakes and reservoirs are important natural resources for irrigation, public supply, wetlands and wildlife.  Excess precipitation that flows into these sources is called runoff, and it's an important drought indicator.  The California Water Science Center tracks both monthly and annual runoff. 

Date published: December 18, 2018

Mojave River and Morongo Groundwater Basins Data

Interactive map of the Mojave and Morongo groundwater basins.  Data layers include sites and data for groundwater levels, water quality, and land subsidence.  Groundwater data spans 1992 to the present.

Date published: December 18, 2018

Drought & Surface Water in California

Careful observation and analysis of the movement and condition of surface water is essential for understanding this resource, especially during times of drought. The California Water Science Center uses a network of more than 500 streamgages to collect real-time data on surface water at locations across the state.

Date published: December 18, 2018

San Antonio Creek Valley Hydrologic Monitoring

In order to understand the integrated hydrologic systems in the San Antonio Creek Valley, many different types of data are being gathered from both the surface water and groundwater system. Learn about these data types and explore them with the interactive map.

Date published: December 17, 2018

Central Valley: Drought Indicators

During the recent droughts of 2007-2010 and 2012-2017, groundwater pumping has increased from the combined effects of the drought and land-use changes, re-initiating land subsidence. In order to document historical subsidence and monitor continued changes, the USGS has gathered and interpreted data from a variety of sources.

Date published: December 17, 2018

Benchmark Site Data | San Joaquin Valley, CA

These 5 northern benchmarks in the San Joaquin Valley are where the largest magnitude of subsidence was recently measured using repeat surveys. That doesn't mean these locations are where the largest magnitude of subsidence occurred, just where it's been measured. The southernmost benchmark in this set is where the largest magnitude was historically measured using repeat surveys.

Date published: December 17, 2018

Compaction | Data from Central Valley, CA Extensometers

Aquifer-system compaction has been monitored at selected locations for various periods with borehole extensometers by different agencies, including the USGS, DWR, SLDMWA, and CCID, and by Luhdorff and Scalmanini Consulting Engineers.  This dataset contains compaction data for 23 extensometers across California's Central Valley.

Date published: December 17, 2018

Continuous Global Positioning System (CGPS) Stations

The CGPS data were obtained from the UNAVCO Plate Boundary Observatory (PBO) network of continuously operating GPS stations. The PBO is the geodetic component of UNAVCO, a consortium of research institutions whose focus is measuring vertical and horizontal plate boundary deformation across the North American and Pacific Plates in the western U.S. using high-precision measurement techniques....

Date published: December 17, 2018

InSAR | Central Valley Areas of Interest

The InSAR technique uses two SAR scenes of the same area taken at different times which are then processed together to produce maps called interferograms that show relative land-surface-elevation change between the two SAR acquisition dates. This Areas of Interest dataset is where InSAR data has been interpreted to produce a time-history of subsidence in the Central Valley, CA.

Date published: December 14, 2018

Water Quality Sites, San Bernardino County, CA

List of USGS sites in San Bernardino County, CA that have water quality data samples.  Data is on the USGS National Water Information System database.

Filter Total Items: 481
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Year Published: 2009

Distribution and Joint Fish-Tag Survival of Juvenile Chinook Salmon Migrating through the Sacramento-San Joaquin River Delta, California, 2008

Acoustic telemetry was used to obtain the movement histories of 915 juvenile fall-run Chinook salmon (Oncorhynchus tshawytscha) through the lower San Joaquin River and Sacramento-San Joaquin Delta, California, in 2008. Data were analyzed within a release-recapture framework to estimate survival, route distribution, and detection probabilities...

Holbrook, Christopher M.; Perry, Russell W.; Adams, Noah S.
Distribution and Joint Fish-Tag Survival of Juvenile Chinook Salmon Migrating through the Sacramento-San Joaquin River Delta, California, 2008; 2009; OFR; 2009-1204; Holbrook, Christopher M.; Perry, Russell W.; Adams, Noah S.

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Year Published: 2009

Total selenium and selenium species in irrigation drain inflows to the Salton Sea, California, October 2008 and January 2009

This report presents the results for two sampling periods (October 2008 and January 2009) during a 4-year monitoring program to characterize selenium concentrations in selected irrigation drains flowing into the Salton Sea, California. Total selenium, selenium species (dissolved selenite, selenate, organoselenium), and total suspended solids were...

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 2008 and January 2009; 2009; OFR; 2009-1123; May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.

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Year Published: 2009

Population Dynamics of Adult Lost River (Deltistes luxatus) and Shortnose (Chasmistes brevirostris) Suckers in Clear Lake Reservoir, California, 2006-08

We report results from ongoing research into the population dynamics of endangered Lost River and shortnose suckers in Clear Lake Reservoir, California. Results are included for sampling that occurred from fall 2006 to spring 2008. We summarize catches and passive integrated transponder tagging efforts from trammel net sampling in fall 2006 and...

Barry, Patrick M.; Janney, Eric C.; Hewitt, David A.; Hayes, Brian S.; Scott, Alta C.
Population Dynamics of Adult Lost River (Deltistes luxatus) and Shortnose (Chasmistes brevirostris) Suckers in Clear Lake Reservoir, California, 2006-08; 2009; OFR; 2009-1109; Barry, Patrick M.; Janney, Eric C.; Hewitt, David A.; Hayes, Brian S.; Scott, Alta C.

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Year Published: 2009

Cone penetration test and soil boring at the Bayside Groundwater Project Site in San Lorenzo, Alameda County, California

Aquifer-system deformation associated with ground-water-level changes is being investigated cooperatively by the U.S. Geological Survey (USGS) and the East Bay Municipal Utility District (EBMUD) at the Bayside Groundwater Project (BGP) near the modern San Francisco Bay shore in San Lorenzo, California. As a part of this project, EBMUD has proposed...

Bennett, Michael J.; Sneed, Michelle; Noce, Thomas E.; Tinsley, John C.
Cone Penetration Test and Soil Boring at the Bayside Groundwater Project Site in San Lorenzo, Alameda County, California; 2009; OFR; 2009-1050; Bennett, Michael J.; Sneed, Michelle; Noce, Thomas E.; Tinsley, John C., III

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Year Published: 2009

Summary of Migration and Survival Data from Radio-Tagged Juvenile Coho Salmon in the Trinity River, Northern California, 2008

The survival of hatchery-origin juvenile coho salmon from the Trinity River Hatchery was estimated as they migrated seaward through the Trinity and Klamath Rivers. The purpose of the study was to collect data for comparison to a similar study in the Klamath River and provide data to the Trinity River Restoration Program. A total of 200 fish fitted...

Beeman, John W.; Hansel, Hal; Juhnke, Steve; Stutzer, Greg
Summary of Migration and Survival Data from Radio-Tagged Juvenile Coho Salmon in the Trinity River, Northern California, 2008; 2009; OFR; 2009-1092; Beeman, John W.; Hansel, Hal; Juhnke, Steve; Stutzer, Greg

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Year Published: 2009

Data files for ground-motion simulations of the 1906 San Francisco earthquake and scenario earthquakes on the Northern San Andreas Fault

This data set contains results from ground-motion simulations of the 1906 San Francisco earthquake, seven hypothetical earthquakes on the northern San Andreas Fault, and the 1989 Loma Prieta earthquake. The bulk of the data consists of synthetic velocity time-histories. Peak ground velocity on a 1/60th degree grid and geodetic displacements from...

Aagaard, Brad T.; Barall, Michael; Brocher, Thomas M.; Dolenc, David; Dreger, Douglas; Graves, Robert W.; Harmsen, Stephen; Hartzell, Stephen H.; Larsen, Shawn; McCandless, Kathleen; Nilsson, Stefan; Petersson, N. Anders; Rodgers, Arthur; Sjogreen, Bjorn; Zoback, Mary Lou
Data Files for Ground-Motion Simulations of the 1906 San Francisco Earthquake and Scenario Earthquakes on the Northern San Andreas Fault; 2009; DS; 413; Aagaard, Brad; Barall, Michael; Brocher, Thomas M.; Dolenc, David; Dreger, Douglas; Graves, Robert W.; Harmsen, Stephen; Hartzell, Stephen; Larsen, Shawn; McCandless, Kathleen; Nilsson, Stefan; Petersson, N. Anders; Rodgers, Arthur; Sjogreen, Bjorn; Zoback, Mary Lou

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Year Published: 2009

Total selenium and selenium species in irrigation drain inflows to the Salton Sea, California, April and July 2008

This report presents the results for two sampling periods (April 2008 and July 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 (dissolved selenite, selenate, organoselenium), and total suspended solids were...

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, April and July 2008; 2009; OFR; 2009-1011; May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.

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Year Published: 2009

Summary of Survival Data from Juvenile Coho Salmon in the Klamath River, Northern California, 2008

A study to estimate the effects of Iron Gate Dam discharge on ESA-listed juvenile coho salmon during their seaward migration to the ocean was begun in 2005. Estimates of survival through various reaches of river downstream from the dam were completed in 2006, 2007, and 2008 as part of this process. This report describes the estimates of survival...

Beeman, John W.; Juhnke, Steven; Hansel, Hal C.
Summary of Survival Data from Juvenile Coho Salmon in the Klamath River, Northern California, 2008; 2009; OFR; 2009-1019; Beeman, John W.; Juhnke, Steven; Hansel, Hal C.

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Year Published: 2009

A search in strainmeter data for slow slip associated with triggered and ambient tremor near Parkfield, California

We test the hypothesis that, as in subduction zones, slow slip facilitates triggered and ambient tremor in the transform boundary setting of California. Our study builds on the study of Peng et al. (2009) of triggered and ambient tremor near Parkfield, California during time intervals surrounding 31, potentially triggering, M ≥ 7.5 teleseismic...

Smith, E.F.; Gomberg, J.
A search in strainmeter data for slow slip associated with triggered and ambient tremor near Parkfield, California; 2009; Article; Journal; Journal of Geophysical Research B: Solid Earth; Smith, E. F.; Gomberg, J.

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Year Published: 2009

Habitat requirements of the endangered California freshwater shrimp (Syncaris pacifica) in lagunitas and Olema creeks, Marin County, California, USA

This study was conducted to better understand the habitat requirements and environmental limiting factors of Syncaris pacifica, the California freshwater shrimp. This federally listed endangered species is native to perennial lowland streams in a few watersheds in northern California. Field sampling occurred in Lagunitas and Olema creeks at...

Martin, Barbara A.; Saiki, Michael K.; Fong, Darren
Habitat requirements of the endangered California freshwater shrimp (Syncaris pacifica) in lagunitas and olema creeks, Marin County, California, USA; 2009; Article; Journal; Journal of Crustacean Biology; Martin, B. A.; Saiki, M. K.; Fong, D.

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Year Published: 2009

Linking habitat quality with trophic performance of steelhead along forest gradients in the South Fork Trinity River Watershed, California

We examined invertebrate prey, fish diet, and energy assimilation in relation to habitat variation for steelhead Oncorhynchus mykiss (anadromous rainbow trout) and rainbow trout in nine low-order tributaries of the South Fork Trinity River, northern California. These streams spanned a range of environmental conditions, which allowed us to use...

McCarthy, Sarah G.; Duda, Jeffrey J.; Emlen, John M.; Hodgson, Garth R.; Beauchamp, David A.

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Year Published: 2009

Moderate rates of late Quaternary slip along the northwestern margin of the Basin and Range Province, Surprise Valley fault, northeastern California

The 86-km-long Surprise Valley normal fault forms part of the active northwestern margin of the Basin and Range province in northeastern California. We use trench mapping and radiocarbon, luminescence, and tephra dating to estimate displacements and timing of the past five surface-rupturing earthquakes on the central part of the fault near...

Personius, Stephen F.; Crone, Anthony J.; Machette, Michael N.; Mahan, Shannon; Lidke, David J.
Moderate rates of late Quaternary slip along the northwestern margin of the Basin and Range Province, Surprise Valley fault, northeastern California; 2009; Article; Journal; Journal of Geophysical Research B: Solid Earth; Personius, Stephen F.; Crone, Anthony J.; Machette, Michael N.; Mahan, Shannon A.; Lidke, David J.

Filter Total Items: 1,116
Tidal marsh or wetland area with little rivulets winding their way through the marshland.
June 26, 2018

Tidal marsh near San Pablo Bay

Lower Tubbs Island is a tidal marsh near Midshipman Point in northern San Pablo Bay, California, and is part of the San Pablo Bay National Wildlife Refuge. Historically, Tubbs Island was used as a club for duck hunters, protected by levees that could be opened with the tides to release salt water into the sloughs. In 1969, it was purchased by the Nature Conservancy, and in

...
Vehicles cross over a amphibian passage on a forest road via an elevated road segment
June 2, 2018

Vehicles Using An Elevated Road Segment Over Wildlife Passage

Vehicles drive on an elevated road segment that allows amphibians and reptiles to pass safely beneath and cross the road.

May 31, 2018

PubTalk 5/2018 — Yes Humans really are causing induced earthquakes

Title: Yes, Humans Really Are Causing Earthquakes! How Energy Industry Practices are Causing Earthquakes in America's Heartland

  • In every year since 2014, Oklahoma has had more earthquakes than California.
  • Oil and gas operations are "inducing" these earthquakes.
  • The earthquake rate has dropped by more than 50 percent due to changes in industry
Attribution:
Vegetation in foreground up on a beach bluff above flat beach with waves.
May 23, 2018

Sunset State Beach Video Camera 1 bright image

Two video cameras overlook the coast at Sunset State Beach in Watsonville, California. Camera 1 looks northwest while Camera 2 looks north. Every half hour during daylight hours, the cameras collect snapshots and video for 10 minutes. The various imagery collected:

  • Snapshot: first frame of the video, just like a standard photo
  • Timex (time-exposure):
...
Vegetation in foreground up on a beach bluff above flat beach with waves.
May 23, 2018

Sunset State Beach Video Camera 1 dark image

Two video cameras overlook the coast at Sunset State Beach in Watsonville, California. Camera 1 looks northwest while Camera 2 looks north. Every half hour during daylight hours, the cameras collect snapshots and video for 10 minutes. The various imagery collected:

  • Snapshot: first frame of the video, just like a standard photo
  • Timex (time-exposure):
...
Vegetation in foreground up on a beach bluff above flat beach with waves.
May 23, 2018

Sunset State Beach Video Camera 1 snapshot

Two video cameras overlook the coast at Sunset State Beach in Watsonville, California. Camera 1 looks northwest while Camera 2 looks north. Every half hour during daylight hours, the cameras collect snapshots and video for 10 minutes. The various imagery collected:

  • Snapshot: first frame of the video, just like a standard photo
  • Timex (time-exposure):
...
Vegetation in foreground up on a beach bluff above flat beach with waves.
May 23, 2018

Sunset State Beach Video Camera 1 time-exposure

Two video cameras overlook the coast at Sunset State Beach in Watsonville, California. Camera 1 looks northwest while Camera 2 looks north. Every half hour during daylight hours, the cameras collect snapshots and video for 10 minutes. The various imagery collected:

  • Snapshot: first frame of the video, just like a standard photo
  • Timex (time-exposure):
...
Vegetation in foreground up on a beach bluff above flat beach with waves.
May 23, 2018

Sunset State Beach Video Camera 1 variance image

Two video cameras overlook the coast at Sunset State Beach in Watsonville, California. Camera 1 looks northwest while Camera 2 looks north. Every half hour during daylight hours, the cameras collect snapshots and video for 10 minutes. The various imagery collected:

  • Snapshot: first frame of the video, just like a standard photo
  • Timex (time-exposure):
...
Vegetation in foreground up on a beach bluff above flat beach with waves.
May 23, 2018

Sunset State Beach Video Camera 2 bright image

Two video cameras overlook the coast at Sunset State Beach in Watsonville, California. Camera 1 looks northwest while Camera 2 looks north. Every half hour during daylight hours, the cameras collect snapshots and video for 10 minutes. The various imagery collected:

  • Snapshot: first frame of the video, just like a standard photo
  • Timex (time-exposure):
...
Coastal flowers in foreground up on a beach bluff above flat beach with waves gently lapping, sky is cloudy in the distance.
May 23, 2018

Sunset State Beach Video Camera 1 Snapshot

Image from video camera overlook the coast at Sunset State Beach in Watsonville, CA. Every half hour during daylight hours, the camera shoots video for 10 minutes. This snapshot is the first frame in the 10-minute sequence.

Vegetation in foreground up on a beach bluff above flat beach with waves.
May 23, 2018

Sunset State Beach Video Camera 2 dark image

Two video cameras overlook the coast at Sunset State Beach in Watsonville, California. Camera 1 looks northwest while Camera 2 looks north. Every half hour during daylight hours, the cameras collect snapshots and video for 10 minutes. The various imagery collected:

  • Snapshot: first frame of the video, just like a standard photo
  • Timex (time-exposure):
...
Vegetation in foreground up on a beach bluff above flat beach with waves.
May 23, 2018

Sunset State Beach Video Camera 2 snapshot

Two video cameras overlook the coast at Sunset State Beach in Watsonville, California. Camera 1 looks northwest while Camera 2 looks north. Every half hour during daylight hours, the cameras collect snapshots and video for 10 minutes. The various imagery collected:

  • Snapshot: first frame of the video, just like a standard photo
  • Timex (time-exposure):
...
Filter Total Items: 987
Flyer thumbnail
April 22, 2015

Everyone knows that California is “earthquake country,” but it is also “volcano country.” The most recent large volcanic eruption in California was 100 years ago at Lassen Peak, in what is now Lassen Volcanic National Park. California is much different today than it was 100 years ago; in 1915 there were no deaths, no injuries, and minimal economic losses due to the eruption.

USGS
April 14, 2015

The U.S. Geological Survey and Clear Channel Outdoor today announced a partnership to provide the public with critical earthquake safety information during April.

Image: Tsunami Evacuation Sign
April 13, 2015

Tens of thousands of people along the U.S. Pacific Northwest coastline may not have enough time to evacuate low-lying areas before tsunami waves arrive, according to a new publication by researchers at the U.S. Geological Survey, University of Colorado Boulder, and California State University, Sacramento.

Image: Female Golden Eagle with GPS-GSM Transmitter
April 8, 2015

Golden eagles in the Mojave Desert travel farther, to different areas, and at different times of the year than previously understood, according to research by the U.S. Geological Survey and partners from other federal agencies, academia and the private sector. 

Screenshot of the Upper Klamath Basin Collaborative Groundwater Monitoring website.
April 3, 2015

The U.S. Geological Survey recently launched the Upper Klamath Basin Collaborative Groundwater Monitoring  website to provide information on groundwater conditions in the upper Klamath Basin.

Plot of earthquakes in Mount Shasta region greater than M1.0 from A...
April 3, 2015

Since February 19, 2015 an ongoing series of small earthquakes has been occurring approximately 5 miles southeast of the summit of Mount Shasta, near the Clear Creek Trailhead on a regional, unnamed fault at about 3-5 miles depth.

Updated 2015 version of the El Capitan, California quadrangle with orthoimage turned off
April 1, 2015

Several of the 2,798 new US Topo quadrangles for California now display public trails along with segments of the Pacific Crest National Scenic Trail. Also the new maps now show improved data layers such as public land survey information, map symbol redesign, enhanced railroad information and new road source data.

Image: Happy Cows in Happy Flowers
March 25, 2015

Grassland habitats on rangelands in California’s Central Valley and surrounding foothills could decline by as much as 37 percent by 2100 due to changes in land use and climate, according to new scientific projections by the U.S. Geological Survey.

Image: San Jose Earthquakes' Avaya Stadium
March 20, 2015

Where better to install a new earthquake sensor than in the new home of the San Jose Earthquakes Major League Soccer team? 

3D perspective view of the likelihood that each region of California will experience a magnitude 6.7 within 30 years
March 10, 2015

A new California earthquake forecast by the U.S. Geological Survey and partners revises scientific estimates for the chances of having large earthquakes over the next several decades.