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: 393
Date published: June 8, 2017
Status: Active

Delineation of Flood-Inundation Areas in Grapevine Canyon near Scotty’s Castle, Death Valley National Park, California

On October 18, 2015 an intense, nearly stationary, thunderstorm triggered flooding in Grapevine Canyon. Grapevine Canyon Road, power and water infrastructure, and several buildings at Scotty’s Castle were damaged by the flood water, necessitating closure of the area to the public. In response to the flood event, the National Park Service requested the USGS Nevada Water Science Center perform a...

Date published: June 1, 2017
Status: Completed

Back to the Future on the San Andreas Fault

Release Date: JUNE 1, 2017

Investigating Past Earthquakes to Inform the Future

What does the science say? Where does the information come from? And what does it mean? Investigating past earthquakes to inform the future. Maybe you’ve heard that the “Big One is overdue” on the San Andreas Fault. No one can predict earthquakes, so what does the science really say? Where...

Date published: May 31, 2017
Status: Active

Big Sur Landslide

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: May 26, 2017
Status: Active

Estimating Annual Groundwater Discharge by Evapotranspiration Along the Wild and Scenic Portion of the Amargosa River

The USGS Nevada Water Science Center is refining estimates of annual groundwater discharge along the Wild and Scenic portion of the Amargosa River (AWSR) and adjacent spring discharge areas. Discharge estimates will be based on evapotranspiration (ET) measurements made along the Amargosa River during a 2-year period, previous estimates of evapotranspiration rates, and remote sensing techniques...

Contacts: Michael Pavelko
Date published: April 27, 2017
Status: Completed

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.

Filter Total Items: 519
Date published: January 1, 2018

Central California CoSMoS v3.1 projections of shoreline change due to 21st century sea-level rise

This dataset contains projections of shoreline positions and uncertainty bands for future scenarios of sea-level rise. Projections were made using the Coastal Storm Modeling System - Coastal One-line Assimilated Simulation Tool (CoSMoS-COAST), a numerical model forced with global-to-local nested wave models and assimilated with lidar-derived shoreline vectors. Read metadata carefully.
De...

Date published: January 1, 2018

Geochemical and geophysical data for wells in the Rosedale Ranch oil and gas field

The U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board compiled and analyzed data for the purpose of mapping groundwater salinity in selected oil and gas fields in California. The data for the Rosedale Ranch oil field include well construction data, digitized borehole geophysical data, geochemical analyses of water samples from oil and gas

Date published: January 1, 2018

All Wells, District Boundaries, and Field Boundaries from the California Division of Oil, Gas, and Geothermal Resources (DOGGR)

There are 487 onshore oil and gas fields in California encompassing 3,392 square miles of aggregated area. The California State Water Resources Control Board (State Water Board) initiated a Regional Monitoring Program (RMP) in July 2015, intended to determine where and to what degree groundwater quality may be at potential risk to contamination related to oil and gas development activ

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

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: 1-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

Water chemistry data for samples collected at groundwater sites near the Fruitvale oil field, September 2016–February 2017, Kern County, California

As part of the California State Water Resources Control Board’s Regional Groundwater Monitoring Program of Water Quality in Areas of Oil and Gas Production, during September 2016–February 2017, the U.S. Geological Survey collected and analyzed groundwater and associated quality-control (QC) samples from 14 water-production wells located within a three mile buffer zone of a

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: January 1, 2018

Structure-from-Motion (SfM) surface models derived from seafloor video from the Channel Islands, California

Structure-from-Motion (SfM) surface models were created using seafloor video collected over a visible fault scarp in the Channel Islands, California, during a 2016 U.S. Geological Survey (USGS) field activity. Four SfM surface models were created, each with a different combination of locating, scaling, and optimizing methods. Video imagery was collected using the USGS Pacific Co

Date published: January 1, 2018

Photographs and video clips of Clear Lake Hitch (Lavinia exilicauda chi)

This data release includes a collection of photographs and video clips. Above water observations were taken with with a Nikon D5300 digital camera and underwater observations were taken with a SOOCOO S100Pro digital camera. All observations were made on April 1, 2018 in Kelsey, Creek, Lake County, California. Further details can be found in: Feyrer, F. 2018. Rapid potamodromy int

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

California Groundwater Ambient Monitoring and Assessment (GAMA) Program Priority Basin Project Study Areas and grid cells for assessment of groundwater resources used for public drinking-water supply.

The California Groundwater Ambient Monitoring and Assessment Program (GAMA) is a statewide, comprehensive assessment of groundwater quality designed to help better understand and identify risks to groundwater resources. GAMA is being implemented by the California State Water Resources Control Board. The USGS is the technical lead for the Priority Basin Project (PBP), one of the compon

Filter Total Items: 355
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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.

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Year Published: 1994

Chapter E. The Loma Prieta, California, Earthquake of October 17, 1989 - Hydrologic disturbances

Seismic events have long been known to cause changes in the level of oceans, streams, lakes, and the water table. The great San Francisco earthquake of 1906 induced significant hydrologic changes that were qualitatively similar to those changes observed for the Loma Prieta earthquake. What is different is that the hydrologic data sets collected...

Rojstaczer, Stuart A.
Chapter E. The Loma Prieta, California, Earthquake of October 17, 1989 - Hydrologic Disturbances; 1994; PP; 1551-E; The Loma Prieta, California, Earthquake of October 17, 1989: Strong Ground Motion and Ground Failure; Edited by Rojstaczer, Stuart A.

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Year Published: 1994

Chapter F. The Loma Prieta, California, Earthquake of October 17, 1989 - Tectonic processes and models

If there is a single theme that unifies the diverse papers in this chapter, it is the attempt to understand the role of the Loma Prieta earthquake in the context of the earthquake 'machine' in northern California: as the latest event in a long history of shocks in the San Francisco Bay region, as an incremental contributor to the regional...

Simpson, Robert W.
Chapter F. The Loma Prieta, California, Earthquake of October 17, 1989 - Tectonic Processes and Models; 1994; PP; 1550-F; The Loma Prieta, California, Earthquake of October 17, 1989: Earthquake Occurrence; Edited by Simpson, Robert W.

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Year Published: 1994

Irrigation water supply and demand data for 1976, 1980, and 1984 for the western San Joaquin Valley, California

This report presents the irrigation water supply and demand data for 1976, 1980, and 1984 for 32 water districts in the western San Joaquin Valley, California. Data are provided for each water district or each of the three years if the data were available. The complete data base is given by water district or each township, range, and section in...

Templin, W.E.; Haltom, T.C.
Irrigation water supply and demand data for 1976, 1980, and 1984 for the western San Joaquin Valley, California; 1994; OFR; 94-335; Templin, W. E.; Haltom, T. C.

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Year Published: 1994

Method to identify wells that yield water that will be replaced by Colorado River water in Arizona, California, Nevada, and Utah

Accounting for the use of Colorado River water is required by the U.S. Supreme Court decree, 1964, Arizona v. California. Water pumped from wells on the flood plain and from certain wells on alluvial slopes outside the flood plain is presumed to be river water and is accounted for as Colorado River water. A method was developed to identify wells...

Wilson, Richard P.; Owen-Joyce, Sandra J.
Method to identify wells that yield water that will be replaced by Colorado River water in Arizona, California, Nevada, and Utah; 1994; WRI; 94-4005; Wilson, Richard P.; Owen-Joyce, Sandra J.

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Year Published: 1993

Chapter C. The Loma Prieta, California, Earthquake of October 17, 1989 - Preseismic observations

The October 17, 1989, Loma Prieta, Calif., Ms=7.1 earthquake provided the first opportunity in the history of fault monitoring in the United States to gather multidisciplinary preearthquake data in the near field of an M=7 earthquake. The data obtained include observations on seismicity, continuous strain, long-term ground displacement, magnetic...

Johnston, Malcolm J. S.
Chapter C. The Loma Prieta, California, Earthquake of October 17, 1989 - Preseismic Observations; 1993; PP; 1550-C; The Loma Prieta, California, Earthquake of October 17, 1989: Earthquake Occurrence; Edited by Johnston, Malcolm J. S.

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Year Published: 1993

The Loma Prieta, California, Earthquake of October 17, 1989: Earthquake occurrence

Professional Paper 1550 seeks to understand the M6.9 Loma Prieta earthquake itself. It examines how the fault that generated the earthquake ruptured, searches for and evaluates precursors that may have indicated an earthquake was coming, reviews forecasts of the earthquake, and describes the geology of the earthquake area and the crustal forces...

Coordinated by Bakun, William H.; Prescott, William H.
The Loma Prieta, California, Earthquake of October 17, 1989: Earthquake Occurrence; 1993; PP; 1550; Coordinated by Bakun, William H.; Prescott, William H.

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Year Published: 1993

The Loma Prieta, California, Earthquake of October 17, 1989: Societal response

Professional Paper 1553 describes how people and organizations responded to the earthquake and how the earthquake impacted people and society. The investigations evaluate the tools available to the research community to measure the nature, extent, and causes of damage and losses. They describe human behavior during and immediately after the...

Coordinated by Mileti, Dennis S.
The Loma Prieta, California, Earthquake of October 17, 1989: Societal Response; 1993; PP; 1553; Coordinated by Mileti, Dennis S.

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Year Published: 1993

The Loma Prieta, California, earthquake of October 17, 1989 - Public response: Chapter B in The Loma Prieta, California, earthquake of October 17, 1989: Societal Response (Professional Paper 1553)

Major earthquakes provide seismologists and engineers an opportunity to examine the performance of the Earth and the man-made structures in response to the forces of the quake. So, too, do they provide social scientists an opportunity to delve into human responses evoked by the ground shaking and its physical consequences. The findings from such...

Bolton, Patricia A.
Chapter B. The Loma Prieta, California, Earthquake of October 17, 1989 - Public Response; 1993; PP; 1553-B; The Loma Prieta, California, Earthquake of October 17, 1989: Societal Response; Edited by Bolton, Patricia A.

Filter Total Items: 1,005
A man on left talks to a news reporter who holds a microphone while he speaks.
December 9, 2017

USGS talks to reporter

KION-TV reporter Ashley Keehn (right) asked PCMSC Director Guy Gelfenbaum about why we held this open house.

A crowd of people stand in a lobby talking in small groups and looking at various exhibits.
December 9, 2017

USGS Santa Cruz open house

Visitors and staff filled our lobby for several hours.

A woman holding a video camera on a tripod aimed at another woman who's pointing at something and talking to a young student
December 9, 2017

TV camera records scene at Open House

Emma Kelsey (right) explained seabird biology to visitors as a TV camera recorded the scene. 

A man and two women crouch around a table with a computer screen that one of the women is pointing to while she talks.
December 9, 2017

Sharing information on the screen

Visitors watched closely as Alicia Balster-Gee (in green vest) presented our research on marine geohazards in Alaska.

A woman facing the camera talks to two men with their backs to the camera.
December 9, 2017

USGS Open House discussions

Members of the PCMSC Marine Minerals Team, including physical science technician Kira Mizell (center), took turns describing the importance of seafloor minerals.

A man at right talks about and gestures at a rock on a table to another man who is squatting in front of the rock.
December 9, 2017

Talking about seafloor mineral deposits

Research geologist Jim Hein (right) gave a hands-on explanation of seafloor mineral deposits.

A woman kneeling on the floor helps a young girl try on tall adult-sized rubber boots, for fun.
December 9, 2017

Try these on for size

Li Erikson (right) helped a young visitor try on the tall boots needed for Alaskan coastal research.

A man at right talks with another man and woman about an image projected on a screen.
December 9, 2017

Drone discussion

The drone on the table helped map a giant Big Sur landslide that closed California’s Highway 1. Josh Logan (right) described the process to visitors.

A man shows a young girl some reading material he picked up from table, other people stand in background looking at other stuff.
December 9, 2017

Colorful handouts from USGS

Our handouts were very popular with both kids and adults.

A man talks and gestures, to two elderly people looking on a computer screen.
December 9, 2017

Discussing exhibit at open house

Patrick Barnard (left) explained detailed computer forecasts of coastal flooding and erosion driven by climate change.

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.

Filter Total Items: 938
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.

Magnitude 3.8 earthquake (large purple dot) located about 18 km SE ...
October 21, 2013

A magnitude 3.8 earthquake occurred on October 21, 2013 at 10:04 PDT 18 km (11 miles) SE of the town of Mammoth Lakes in eastern California.