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: 377
Date published: April 27, 2017

Evaluation of Groundwater Flow in the Southern Part of the Amargosa Desert, Nevada and California

Since the original publication of the Death Valley regional groundwater flow system (DVRFS) numerical model in 2004, more information on the regional groundwater flow system in the form of new data and interpretations has been compiled. Cooperators such as the Bureau of Land Management, National Park Service, U.S. Fish and Wildlife Service, the Department of Energy, and Nye County, Nevada,...

Contacts: Wayne Belcher
Date published: April 19, 2017
Status: Active

Epidemiology of Infectious and Other Diseases in Agassiz’s Desert Tortoise

Agassiz’s Desert Tortoise (Gopherus agassizii) was listed as threatened in 1990 under the Endangered Species Act. WERC’s Dr. Kristin Berry leads studies on the cause of diseases in populations of Agassiz’s Desert Tortoise across the Mojave and western Sonoran deserts in southern California.

Contacts: Kristin Berry
Date published: April 13, 2017

Integrated Wildland Fire Science

The size and number of large wildland fires in the western United States have grown dramatically over the past decade, with a contingent rise in damages and suppression costs. This trend will likely continue with further growth of the wildland urban interface (WUI) into fire prone ecosystems, hazardous fuel conditions from decades of fire suppression, and a potentially increasing effect from...

Date published: April 13, 2017
Status: Active

The Pacific Coastal Fog Project

Coastal marine fog is an important meteorological phenomenon for California.  A cloud—either stratus or stratocumulus—is called “fog” when it is low or touching the ground. Marine fog forms as a result of complex interactions between ocean evaporation, aerosols, atmospheric pressure, vertical air layering, onshore-offshore temperature gradients, and coastal mountain topography. The marine...

Date published: April 12, 2017
Status: Active

Land Use and Climate Change Team

We are a research team focusing on understanding the rates, causes, and consequences of land change across a range of geographic and temporal scales. Our emphasis is on developing alternative future projections and quantifying the impact on environmental systems, in particular, the role of land-use change on ecosystem carbon dynamics.

We are interested in how land-use and climate...

Date published: April 11, 2017
Status: Active

Hydrogeologic and Geothermal Conditions of the Northwest Volcanic Aquifers

Although sparsely populated, this area in southeastern Oregon, northeastern California, northwestern Nevada, and southeastern Idaho has high geothermal heat flow that may be used to generate large amounts of electricity.

Date published: March 9, 2017
Status: Active

Restoring Rare Plants on Public Lands

Ecosystems throughout the U.S. face threats from invasive species and rapid changes to the environment. Dr. Kathryn McEachern is studying the long-term effects of invasive plants and animals, and environmental change on the survival and recovery of rare plants across the 18 California Islands and in the Great Lakes.

Date published: March 3, 2017
Status: Active

Sequoia and Kings Canyon Field Station

The Sequoia and Kings Canyon Field Station is home to research programs that focus on wildfire patterns in Southern California, and the effects of drought on Sierra Nevada forests. Select the "Science" tab for a more comprehensive summary.

Date published: March 3, 2017
Status: Active

Santa Monica Mountains Field Station

Update: The Santa Monica Mountains Field Station is no longer an active USGS field station.

Contacts: Erin Boydston
Date published: February 24, 2017
Status: Active

Santa Cruz Field Station

Scientists at the Santa Cruz Field Station study sea otters and seabirds in their environment. The USGS Western Ecological Research Center has two research missions based in the Santa Cruz region:

Date published: February 23, 2017
Status: Active

San Francisco Bay Estuary Field Station

The San Francisco Bay Field Station is the center of studies on recovering tidal wetland ecosystems and ongoing efforts to balance the restoration of local marshes and the needs of seabirds. Click on the "Science" tab for a comprehensive summary of this station and its research.

Date published: February 21, 2017
Status: Active

San Diego Field Station

The San Diego Field Station is the site of research on golden eagles, endangered amphibians and reptiles, and more. Click on the "Science" tab for a comprehensive summary of this study site's projects.

Filter Total Items: 501
Date published: January 1, 2018

Water chemistry data for samples collected at groundwater and surface-water sites near the Lost Hills and Belridge oil fields, November 2016-September 2017, Kern County, California

An investigation was done by the U.S. Geological Survey, in cooperation with the California State Water Resources Control Board's Program of Regional Groundwater Monitoring of Water Quality in Areas of Oil and Gas Production, to assess the effects of oil and gas production activities on nearby groundwater resources. During November 2016–September 2017, 30 samples were collected at

Date published: January 1, 2018

CoSMoS (Coastal Storm Modeling System) Southern California v3.0 Phase 2 wave-hazard projections: 100-year storm in Channel Islands

Model-derived significant wave height (in meters) for the given storm condition and sea-level rise (SLR) scenario.
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. CoSMoS v3.0 for So

Date published: January 1, 2018

Grain size and bulk density of sediment cores from Little Holland Tract and Liberty Island, Sacramento-San Joaquin Delta, California, 2014

Grain size distribution and bulk density are reported for sediment push cores from two flooded agricultural tracts, Little Holland Tract and Liberty Island, in the Sacramento-San Joaquin Delta, California. Push core samples were collected from 14 sites by the U.S Geological Survey in August, 2014. Each core was analyzed at multiple depths to investigate variations in particle sizes with d

Date published: January 1, 2018

CoSMoS (Coastal Storm Modeling System) Southern California v3.0 Phase 2 wave-hazard projections: 20-year storm in Channel Islands

Model-derived significant wave height (in meters) for the given storm condition and sea-level rise (SLR) scenario.
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. CoSMoS v3.0 for So

Date published: January 1, 2018

In situ geochemical data related to the gold-quartz veins of Grass Valley, California, 2014-2015

In situ geochemical data were obtained for pyrite crystals and native gold from two distinct vein sets in the Grass Valley gold district, California. Samples of the N-S (north-south-trending) veins were collected underground at the Empire Mine State Historic Park and samples of the E-W (east-west-trending) veins were collected from drill core provided by the Idaho-Maryland Mining Corpor

Date published: January 1, 2018

Repeat high-resolution acoustic-backscatter datasets collected between 2014 and 2016 of a field of crescent-shaped rippled scour depressions in northern Monterey Bay, California

Between November 2014 and June 2016 the U.S. Geological Survey, Pacific Coastal and Marine Science Center (PCMSC) conducted eight repeat, high-resolution bathymetry and acoustic-backscatter surveys of a small patch of seafloor offshore Santa Cruz in northern Monterey Bay, California. PCMSC also collected oceanographic time-series data over the same two-year period. This metadata file de

Date published: January 1, 2018

Electron microprobe data for monazite and xenotime used in consideration of gold deposit formation models

The genetic origin of many gold deposits, including Pogo in Alaska, remains controversial with questions as to whether they formed due to magmatic-hydrothermal or metamorphic-hydrothermal fluids. Gaining a better understanding of the formation mechanisms for these deposits is critical for defining proper exploration criteria in gold-bearing regions and production within these deposits. Monaz...

Date published: January 1, 2018

Multichannel minisparker seismic-reflection data of field activity 2015-617-FA; Monterey Bay, offshore central California from 2015-02-23 to 2015-03-06

This data release contains approximately 190 line-kilometers of processed, high-resolution multichannel seismic-reflection (MCS) profiles that were collected aboard the R/V Snavely in 2015 on U.S. Geological Survey cruise 2015-617-FA in Monterey Bay, offshore central California. The majority of MCS profiles collected are oriented north-south across the Monterey Canyon head to address ma

Date published: December 26, 2017

Hydrodynamic and sediment transport data from San Pablo Bay and China Camp marsh (northern San Francisco Bay), 2013-2016

The USGS Pacific Coastal and Marine Science Center collected data to investigate sediment dynamics in the shallows of San Pablo Bay (SP) and sediment exchange between bay shallows and the tidal salt marsh in China Camp State Park (CMC) in a series of deployments between December 2013 and June 2016. This data release includes two related groups of data sets, one for SP and one for CMC.

Date published: December 12, 2017

River-channel topography, grain size, and turbidity records from the Carmel River, California, before, during, and after removal of San Clemente Dam

The San Clemente Dam, built in the 1920s on the Carmel River in Monterey County, California, was removed during 2014 and 2015. The dam-removal project was the largest in California to date, and one of the largest in the U.S. The USGS collected data before, during, and after the removal of the dam to study how the river channel's topographic profiles and sediment distributions changed...

Date published: November 16, 2017

Multibeam bathymetry and acoustic-backscatter data collected in 2016 in Catalina Basin, southern California and merged multibeam bathymetry datasets of the northern portion of the Southern California Continental Borderland

In February 2016 the University of Washington in cooperation with USGS PCMSC collected multibeam bathymetry and acoustic-backscatter data in and near the Catalina Basin, southern California aboard the University of Washington's Research Vessel Thomas G. Thompson. Data was collected using a hull-mounted Kongsberg EM300 multibeam...

Date published: October 30, 2017

Hydrogen stable isotope data for: 'Mechanisms associated with an advance in the timing of seasonal reproduction in an urban songbird'

This dataset includes stable hydrogen isotope values of the nonexchangeable hydrogen contained in the outer most secondary feathers of dark-eyed juncos (Junco hyemalis thurberi) collected from the University of California San Diego campus in La Jolla, California in 2014.

Filter Total Items: 351
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Year Published: 1998

The Loma Prieta, California, Earthquake of October 17, 1989: Performance of the built environment

Professional Paper 1552 focuses on the response of buildings, lifelines, highway systems, and earth structures to the earthquake. Losses to these systems totaled approximated $5.9 billion. The earthquake displaced many residents from their homes and severely disrupted transportation systems. Some significant findings were: * Approximately 16,...

Coordinated by Holzer, Thomas L.
The Loma Prieta, California, Earthquake of October 17, 1989: Performance of the Built Environment; 1998; PP; 1552; Coordinated by Holzer, Thomas L.

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Year Published: 1997

Drainage-return, surface-water withdrawal, and land-use data for the Sacramento-San Joaquin Delta, with emphasis on Twitchell Island, California

Partial data on drainage returns and surface-water withdrawals are presented for areas of the Sacramento-San Joaquin Delta, California, for March 1994 through February 1996. These areas cover most of the delta. Data are also presented for all drainage returns and some surface-water withdrawals for Twitchell Island, which is in the western part of...

Templin, William E.; Cherry, Daniel E.
Drainage-return, surface-water withdrawal, and land-use data for the Sacramento-San Joaquin Delta, with emphasis on Twitchell Island, California; 1997; OFR; 97-350; Templin, William E.; Cherry, Daniel E.

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Year Published: 1997

Chapter D. The Loma Prieta, California, Earthquake of October 17, 1989 - Aftershocks and postseismic effects

While the damaging effects of the earthquake represent a significant social setback and economic loss, the geophysical effects have produced a wealth of data that have provided important insights into the structure and mechanics of the San Andreas Fault system. Generally, the period after a large earthquake is vitally important to monitor. During...

Reasenberg, Paul A.
Chapter D. The Loma Prieta, California, Earthquake of October 17, 1989 - Aftershocks and Postseismic Effects; 1997; PP; 1550-D; The Loma Prieta, California, Earthquake of October 17, 1989: Earthquake Occurrence; Edited by Reasenberg, Paul A.

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Year Published: 1996

Chapter A. The Loma Prieta, California, Earthquake of October 17, 1989 - Main shock characteristics

The October 17, 1989, Loma Prieta, Calif., earthquake (0004:15.2 G.m.t. October 18; lat 37.036? N., long 121.883? W.; 19-km depth) had a local magnitude (ML) of about 6.7, a surface-wave magnitude (MS) of 7.1, a seismic moment of 2.2x1019 N-m to 3.5x1019 N-m, a source duration of 6 to 15 s, and an average stress drop of at least 50 bars. Slip...

Spudich, Paul
Chapter A. The Loma Prieta, California, Earthquake of October 17, 1989 - Main Shock Characteristics; 1996; PP; 1550-A; The Loma Prieta, California, Earthquake of October 17, 1989: Earthquake Occurrence; Edited by Spudich, Paul

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Year Published: 1996

Riparian vegetation and its water use during 1995 along the Mojave River, Southern California

The extent and areal density of riparian vegetation, including both phreatophytes and hydrophytes, were mapped along the 100-mile main stem of the Mojave River during 1995. Mapping was aided by vertical false-color infrared and low-level oblique photographs. However, positive identification of plant species and plant physiological stress required...

Lines, Gregory C.; Bilhorn, Thomas W.
Riparian vegetation and its water use during 1995 along the Mojave River, Southern California; 1996; WRI; 96-4241; Lines, Gregory C.; Bilhorn, Thomas W.

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Year Published: 1995

Water-resources data network evaluation for Monterey County, California; Phase 2, northern and coastal areas of Monterey County

This report presents an evaluation of water- resources data-collection networks in the northern and coastal areas of Monterey County, California. This evaluation was done by the U.S. Geological Survey in cooperation with the Monterey County Flood Control and Water Conservation District to evaluate precipitation, surface water, and ground water...

Templin, W.E.; Smith, P.E.; DeBortoli, M.L.; Schluter, R.C.
Water-resources data network evaluation for Monterey County, California; Phase 2, northern and coastal areas of Monterey County; 1995; WRI; 95-4210; Templin, W. E.; Smith, P. E.; DeBortoli, M. L.; Schluter, R. C.

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Year Published: 1995

Land use and water use in the Antelope Valley, California

Urban land use and water use in the Antelope Valley, California, have increased significantly since development of the valley began in the late 1800's.. Ground water has been a major source of water in this area because of limited local surface-water resources. Ground-water pumpage is reported to have increased from about 29,000 acre-feet in 1919...

Templin, William E.; Phillips, Steven P.; Cherry, Daniel E.; DeBortoli, Myrna L.; Haltom, T.C.; McPherson, Kelly R.; Mrozek, C.A.
Land use and water use in the Antelope Valley, California; 1995; WRI; 94-4208; Templin, W. E.; Phillips, S. P.; Cherry, D. E.; DeBortoli, M. L.; Haltom, T. C.; McPherson, K. R.; Mrozek, C. A.

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Year Published: 1995

Look before you build; geologic studies for safer land development in the San Francisco Bay area

This Circular provides a general description of the types of geologic hazards that exist throughout the United States. In nontechnical language this book describes how geologic information can be incorporated in the land-use development process and contains useful discussion of several examples from the San Francisco Bay area and elsewhere in the...

Blair-Tyler, Martha
Look before you build; geologic studies for safer land development in the San Francisco Bay area; 1995; CIR; 1130; Blair-Tyler, Martha

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Year Published: 1994

Accounting for Consumptive Use of Lower Colorado River Water in Arizona, California, Nevada, and Utah

In the Colorado River valley between the east end of Lake Mead and the international boundary with Mexico (see figure), the river is the principal source of water for agricultural, domestic, municipal, industrial, hydroelectric-power generation, and recreational purposes. Water is stored in surface reservoirs and in the river aquifer---permeable...

Owen-Joyce, Sandra J.; Wilson, Richard P.
Accounting for Consumptive Use of Lower Colorado River Water in Arizona, California, Nevada, and Utah; 1994; FS; 074-94; Owen-Joyce, Sandra J.; Wilson, Richard P.

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Year Published: 1994

Chapter A. The Loma Prieta, California, Earthquake of October 17, 1989 - Loss estimation and procedures

This Professional Paper includes a collection of papers on subjects ranging from evaluation of building safety, to human injuries, to correlation of ground deformation with building damage. What these papers share is a common goal to improve the tools available to the research community to measure the nature, extent, and causes of damage and...

Tubbesing, Susan K.
Chapter A. The Loma Prieta, California, Earthquake of October 17, 1989 - Loss Estimation and Procedures; 1994; PP; 1553-A; The Loma Prieta, California, Earthquake of October 17, 1989: Societal Response; Edited by Tubbesing, Susan K.

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Year Published: 1994

Chapter A. The Loma Prieta, California, Earthquake of October 17, 1989 - Strong ground motion

Strong ground motion generated by the Loma Prieta, Calif., earthquake (MS~7.1) of October 17, 1989, resulted in at least 63 deaths, more than 3,757 injuries, and damage estimated to exceed $5.9 billion. Strong ground motion severely damaged critical lifelines (freeway overpasses, bridges, and pipelines), caused severe damage to poorly constructed...

Borcherdt, Roger D.
Chapter A. The Loma Prieta, California, Earthquake of October 17, 1989 - Strong Ground Motion; 1994; PP; 1551-A; The Loma Prieta, California, Earthquake of October 17, 1989: Strong Ground Motion and Ground Failure; Edited by Borcherdt, Roger D.

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Year Published: 1994

Chapter C. The Loma Prieta, California, Earthquake of October 17, 1989 - Fire, police, transportation and hazardous materials

The papers in this chapter discuss some of the failures and successes that resulted from the societal response by a multitude of agencies to the Loma Prieta earthquake. Some of the lessons learned were old ones relearned. Other lessons were obvious ones which had gone unnoticed. Still, knowledge gained from past earthquakes spawned planning and...

Van Anne, Craig; Scawthorn, Charles R.
Chapter C. The Loma Prieta, California, Earthquake of October 17, 1989 - Fire, Police, Transportation and Hazardous Materials; 1994; PP; 1553-C; The Loma Prieta, California, Earthquake of October 17, 1989: Societal Response; Edited by Van Anne, Craig; Scawthorn, Charles R.

Filter Total Items: 962
A woman shows a young child how she uses sediment sieves.
December 9, 2017

Sifting sand with sieves

Research geologist Amy East (left) shows a budding geologist how to sift sand to determine its size during our Open House in Santa Cruz, California.

Two young children sit on top of machines that are not moving, in a yard.
December 9, 2017

Posing for pictures

Posing for pictures on personal watercraft during the USGS Open House in Santa Cruz in December, 2017 was very popular.

A man wearing glasses talks into a microphone while gesturing with his hand.
December 9, 2017

Talking to the news

Open house organizer Rex Sanders explains the wide range of USGS research for a TV interview. Screen capture from KION video.

A young boy sits atop a personal watercraft on the lawn outside a USGS building.
December 9, 2017

Checking out the personal watercraft

A future personal watercraft captain checked out the controls on a beautiful December day in Santa Cruz.

person bent over on barren ground over looking a lake and mountains. A jute net covers the foreground.
December 8, 2017

Scientist spreading moss fragments

A USGS scientist spreads moss fragments for a study to test the restoration potential of moss, an important component of biological soil crust. A jute net, foreground, helps stabilize the moss fragments as they adhere to the soil.

Coastal view of landslide area with sand, gravel, cobbles, and large rocks of all sizes on a slope.
December 7, 2017

Upper terrace of Mud Creek slide

Mud Creek slide from south side of north upper terrace (above north and south berms). Note tension cracks and offset on the terrace to the north.

November 30, 2017

2017 Nov. Pub. Lecture—Sea Otters: Confessions of a Keystone Carnivore

  • Sea otters are perhaps the best-known example of a "keystone predator".
  • Sea otter behavior -- in particular diet specialization and limited mobility -- can mediate their effects on ecosystem dynamics.
  • Other predators, especially large sea stars, can complement and reinforce the keystone role of sea otters: this became apparent with the loss of all
Attribution: Ecosystems
View of a beach from up high on a roof with a pier, gentle waves, and an amusement park far off in the distance.
November 7, 2017

Santa Cruz Main Beach

Still-image from video camera atop the Dream Inn looks eastward over Main Beach and boardwalk in Santa Cruz, CA.

A series of images from various sources of shaded-relief topography show the progression of the Mud Creek landslide area.
November 6, 2017

Mud Creek Shaded-Relief Topography, 2010-2017

A series of images from various sources of shaded-relief topography show the progression of the Mud Creek landslide area, from 2010 through October 12, 2017.

Sources:

  1. lidar data from 2010
  2. lidar data from 2016
  3. structure-from-motion (SfM), March 8, 2017
  4. SfM, May 19, 2017
  5. SfM, May 27, 2017
  6. SfM, May 31, 2017
...
October 26, 2017

2017 Oct. Public Lecture — Global Trends in Mineral Commodity Supplies

  • The U.S. is increasingly reliant on supply of mineral raw materials from other countries.
  • Advanced technologies are increasingly making use of nearly the entire periodic table of the elements.
  • Dynamic studies of critical and strategic mineral supply and demand can identify emerging potential supply risks.
  • The USGS - National Minerals
October 19, 2017

Can Prescribed Fire Help Forests Survive Drought in the Sierra Nevadas

This webinar was conducted as part of the Climate Change Science and Management Webinar Series, held in partnership by the USGS National Climate Change and Wildlife Science Center and the FWS National Conservation Training Center. 

Webinar Summary: Prescribed fire is commonly used by managers in the western U.S. to remove potential wildfire fuel, such as small trees

October 16, 2017

Image of the Week - Wildfires Devastate California Wine Country

Strong winds are quickly spreading wildfire across California's wine country, as seen in these two Landsat 8 images.

At the USGS EROS Center, we study land change, operate the Landsat satellites, and maintain the longest, continuously acquired collection of images of the Earth's land surface.

USGS EROS Center (

Filter Total Items: 927
Screenshot Location of Mammoth Mountain
February 6, 2014

An earthquake swarm under Mammoth Mountain (Mono County, CA), which started slowly on February 3, 2014 intensified in the early hours of February 5 with many small-magnitude earthquakes occurring in rapid succession, a phenomenon known as "spasmodic bursts."

USGS science for a changing world logo
January 21, 2014

What is all the buzz about in the Yellowstone area? Is it really dangerous? On January 23rd Jake Lowenstern, Scientist-in-Charge of Yellowstone Volcano Observatory will explain what is happening now with earthquakes, ground uplift, and steam explosions.

Image: Gary Scoppettone
January 16, 2014

Today, the Department of Interior honored U.S. Geological Survey biologist Gary Scoppettone and his colleagues for helping land managers save two species of fish from extinction. The species of unique desert fish, Cui-ui and Lahontan cutthroat trout, are considered sacred to the Pyramid Lake Paiute Tribe of Nevada.

USGS science for a changing world logo
January 15, 2014

Twenty years ago this week an earthquake struck Northridge, Calif., killing 57 people and revealing a serious defect in a common type of mid-rise building. A new study by U.S. Geological Survey and Caltech engineers, shows that these mid-rise buildings with fracture-prone welds in their steel frames are much more dangerous than they would be if they met current standards.

USGS science for a changing world logo
January 15, 2014

Trees do not slow in their growth rate as they get older and larger — instead, their growth keeps accelerating, according to a study published today in the journal Nature.

USGS
December 19, 2013

Secretary of the Interior Sally Jewell announced today that Interior’s Southwest Climate Science Center is awarding nearly $1.2 million to universities and other partners for research to guide managers of parks, refuges and other cultural and natural resources in planning how to help species and ecosystems adapt to climate change.

USGS
December 13, 2013

Drought conditions are linked to declines in a protected desert tortoise population in part of the Sonoran Desert, according to a U.S. Geological Survey study. 

USGS
December 6, 2013

The U.S. Geological Survey participates in the American Geophysical Union's fall meeting with hundreds of technical presentations.  Below are some highlights of USGS science at AGU this year. Highlights about the technical sessions are presented in chronological order with session numbers, and room numbers in San Francisco's Moscone Convention Center...

USGS
November 18, 2013

Extensive groundwater pumping from San Joaquin Valley aquifers is increasing the rate of land subsidence, or sinking, that could result in serious operational and structural challenges and repairs to water infrastructure, according to a new report by the U.S. Geological Survey.

USGS
November 7, 2013

Although dousing the flames was foremost in people's minds during the recent Rim Fire in Stanislaus National Forest and Yosemite National Park, U.S. Geological Survey scientific work continues well after the fire is out. USGS scientists are continuing their critical research characterizing the hidden dangers faced after large wildfires.

USGS
November 4, 2013

A new cooperative study by the U.S. Geological Survey and the Hi-Desert Water District indicates that the artificial replenishment of the groundwater aquifer system in the west hydrogeologic unit of the Warren groundwater basin in San Bernardino County’s Yucca Valley resulted in a decrease of nitrate concentrations in groundwater samples and a rise in water levels.

Volcanic eruptions have a much longer warning phase before the onse...
October 29, 2013

On October 6, 2013 the California Office of Emergency Services (CalOES) published its 2013 State of California Multi-Hazard Mitigation Plan complete with a chapter from the USGS on volcano hazard mitigation.