Unified Interior Regions

California

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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.

News

Date published: June 1, 2020

The Blind Zone of Earthquake Early Warning

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

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

Date published: May 13, 2020

Unpacking CalVO's new seismic monitoring boxes

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

Date published: April 22, 2020

Modeling Water Supply and Demand in the Transboundary Rio Grande to Support Long Term Management Strategies

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

Filter Total Items: 369
Small silver metal boat with USGS lettering on the side, water is splashing up on the side and a small wake is formed.
Date Published: June 2, 2020
Status: Active

PCMSC Marine Facility (Marfac)

Marfac is the operational arm of the Pacific Coastal and Marine Science Center. The Marine Facility staff provides mechanical and electronics expertise for field operations along the coast, in the nearshore environment, and in the deeper waters of the ocean.

Contacts: Timothy Elfers
An interactive mapping application in which the user can choose parameters from the menus to create a computer model of flooding
Date Published: June 1, 2020
Status: Active

Coastal Storm Modeling System (CoSMoS)

The Coastal Storm Modeling System (CoSMoS) makes detailed predictions of storm-induced coastal flooding, erosion, and cliff failures over large geographic scales. CoSMoS was developed for hindcast studies, operational applications and future climate scenarios to provide emergency responders and coastal planners with critical storm-hazards information that can be used to increase public safety...

map of Los Angeles area with different gradational colors
Date Published: May 29, 2020
Status: Completed

The Blind Zone of Earthquake Early Warning

Residents in California, Oregon, and Washington have been told that earthquake early warning (EEW) is at their doorstep and will alert them to the shaking from an earthquake before it arrives. Some media reports have said there will be “up to a minute of warning”. The problem is, for onshore earthquakes these claims are exaggerated, and under some conditions a warning is not scientifically or...

Image shows methane bubbling up from the seafloor
Date Published: May 26, 2020
Status: Active

EXPRESS: Expanding Pacific Research and Exploration of Submerged Systems

EXPRESS is a multi-year, multi-institution cooperative research campaign in deep sea areas of California, Oregon, and Washington, including the continental shelf and slope. EXPRESS data and information are intended to guide wise use of living marine resources and habitats, inform ocean energy and mineral resource decisions, and improve offshore hazard assessments.

Periphyton along the Nearshore of Lake Tahoe
Date Published: May 8, 2020
Status: Active

Nutrient Source Identification in Groundwater and Periphyton Along the Nearshore of Lake Tahoe

High concentrations of phosphorus (P) and nitrogen (N) are responsible for excessive, or nuisance algal blooms in many ecosystems world-wide, and climate change is predicted to exacerbate the problem1,2. Excessive nutrients supplied to the nearshore zone of Lake Tahoe may have significant consequences to ecological communities, water clarity, and water quality. The nearshore zone...

Contacts: Ramon C Naranjo
A building after an earthquake has crumbled the roof and brick walls, the interior is now visible.
Date Published: May 1, 2020
Status: Active

U.S. West Coast and Alaska Marine Geohazards

Marine geohazards are sudden and extreme events beneath the ocean that threaten coastal populations. Such underwater hazards include earthquakes, volcanic eruptions, landslides, and tsunamis.

Devastating earthquakes in Japan (2011) and Chile (2010) that spawned pan-oceanic tsunamis sent a sobering reminder that U.S. coastlines are also vulnerable to natural disasters that originate in...

Cartoon shows a cylindrical object that is floating above and scanning a landscape with rocky outcroppings.
Date Published: May 1, 2020
Status: Active

Seafloor Faults off Southern California

More than 22 million people live along Southern California’s coast, and many more migrate there every year. Faults and earthquake threats in this region have been heavily studied on land. USGS aims to boost our knowledge about faults on the seafloor, so they can be included in hazard assessments.

Contacts: Danny Brothers
View from a dock near a calm bay with boats docked and one motoring slowly through the bay with a large outcrop in background.
Date Published: May 1, 2020
Status: Active

Offshore Faults along Central and Northern California

From Point Conception to Cape Mendocino, seafloor faults have been, in the past, mapped in varying ways and without enough detail to assess their earthquake potential. To provide this important information, USGS uses advanced technology to image offshore faults that could trigger devastating earthquakes near densely populated areas and a nuclear power plant.

Contacts: Janet Watt
Land Cover Animation of Palm Springs, CA area
Date Published: April 29, 2020
Status: Active

LCMAP Change Stories: Building a Boomtown, Block by Block

The desert outpost of Palm Springs, California and the surrounding Thousand Palms region has experienced explosive population growth over the past four decades, with tract after tract of development filling in previously barren landscapes along Interstate 10.

Coastal wetland on the Bay of Fundy, New Brunswick, Canada
Date Published: April 17, 2020
Status: Active

The Response of Coastal Wetlands to Sea-level Rise: Understanding how Macroscale Drivers Influence Local Processes and Feedbacks

The purpose of this work is to advance our understanding of how coastal wetland responses to sea-level rise (SLR) within the conterminous United States are likely to vary as a function of local, regional, and macroscale drivers, including climate. Based on our interactions with managers and decision makers, as well as our knowledge of the current state of the science, we propose to: (a)...

aerial view of Paso Robles, CA
Date Published: April 8, 2020
Status: Active

Evaluation of Groundwater Resources in the Adelaida Area of San Luis Obispo County, California

Stakeholders in San Luis Obispo County are concerned that the increased demand for water use has, and will continue to, affect groundwater levels and availability in the Adelaida area. To address stakeholder concerns, the County of San Luis Obispo Board of Supervisors has asked the USGS to conduct a comprehensive evaluation of groundwater resources of the Adelaida area. 

Coastal flowers in foreground up on a beach bluff above flat beach with waves gently lapping, sky is cloudy in the distance.
Date Published: March 2, 2020
Status: Active

Using Video Imagery to Study Coastal Change: Sunset State Beach

Two video cameras overlook the coast at Sunset State Beach in Watsonville, California. Camera 1 looks northwest while Camera 2 looks north. The cameras are part of the Remote Sensing Coastal Change project.

Filter Total Items: 473
Two illustrations to show the landscape around a lake.
May 27, 2020

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

Map shows where samples and data have been collected.
May 18, 2020

We measured currents, suspended-sediment concentration, bed sediment characteristics, and vegetation biomass density in the Sacramento-San Joaquin Delta in 2017-2018, as part of a project investigating the influence of invasive aquatic vegetation on flow and sediment flux. This data release includes data from three sites: Lindsey Slough, Middle River, and lower Mokelumne River.

USGS
May 18, 2020

This part of the data release contains high-resolution acoustic-backscatter data collected by the U.S. Geological Survey (USGS) Pacific Coastal and Marine Science Center at three study locations in the Sacramento-San Joaquin Delta, California. Data were collected in Lindsey Slough in April 2017, Middle River in March 2018, and Mokelumne River in March 2018, using an interferometric ba

USGS
May 18, 2020

These data present suspended particle size distributions collected by the U.S. Geological Survey (USGS) Pacific Coastal and Marine Science Center at three locations in the Sacramento-San Joaquin Delta. Data were collected in Lindsey Slough on April 4 and April 18, 2017, and near the mouth of the Mokelumne River and in Middle River on March 14, 2018 by deploying a Sequoia Scientific Lase

USGS
May 18, 2020

Vegetation type and density data were collected by the U.S. Geological Survey (USGS) Pacific Coastal and Marine Science Center at three locations in the Sacramento-San Joaquin Delta. Data were collected in Lindsey Slough in April 2017, and Middle River and the Mokelumne River in March 2018. Vegetation samples were collected by divers, and used to determine dry biomass density. These data

USGS
May 18, 2020

Bed sediment samples were collected in Lindsey Slough in April 2017, and Middle River and the Mokelumne River in March 2018, to analyze for sediment properties, including bulk density, particle size distribution, and percent organic carbon. Sediment samples were collected within the vegetation with push corers deployed from a small vessel, and in the unvegetated channel with a Gomex b

Map of a western coastline with stretches of the coast labeled to identify data set regions.
May 4, 2020

This dataset contains spatial projections of coastal cliff retreat (and associated uncertainty) for future scenarios of sea-level rise (SLR) in Central California. Present-day cliff-edge positions used as the baseline for projections are also included. Projections were made using numerical models and field observations as part of Coastal Storm Modeling System (CoSMoS). Read metadata carefully.

Mpa shows areas along the California coast where coastal storm modeling system implementations are completed
May 4, 2020

CoSMoS makes detailed predictions over large geographic scales of storm-induced coastal flooding and erosion for both current and future SLR scenarios, as well as long-term shoreline change and cliff retreat. Several versions of CoSMoS have been implemented for areas of the California coast, including Southern California, Central California, and San Francisco Bay.

USGS
May 4, 2020

This data contains maximum model-derived significant wave height (in meters) for the sea-level rise (SLR) and storm condition indicated.
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) scenar

USGS
May 4, 2020

This data contains maximum depth of flooding (cm) in the region landward of the present-day shoreline for the sea-level rise (SLR) and storm condition indicated.
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-le

USGS
May 4, 2020

This data contains maximum model-derived ocean currents (in meters per second) for the sea-level rise (SLR) and storm condition indicated.
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) scen

USGS
May 4, 2020

This data contains maximum model-derived ocean currents (in meters per second) for the sea-level rise (SLR) and storm condition indicated.
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) scen

Filter Total Items: 32
This is a map of the Southwest US with RestoreNet sites in six ecoregions.
May 14, 2020

RestoreNet is a networked ecological experiment on the cutting-edge of restoration science. The experiment sites span dryland ecoystems of the southwest U.S.

Black and grey map of the contiguous 48 states shaded by the number of people using domestic wells per square kilometer (2010)
April 23, 2020

Domestic wells provide drinking water supply for approximately 40 million people in the United States. Knowing the location of these wells, and the populations they serve, is important for identifying heavily used aquifers, locations susceptible to contamination, and populations potentially impacted by poor-quality groundwater. 

volcano exposure storymap
April 1, 2020

A geonarrative summary of the USGS report that provides a broad perspective on California’s exposure to volcanic hazards. By integrating volcanic hazard information with geospatial data on populations, infrastructure, and resources, the results provide estimates of impacts to people and our environment if an eruption were to occur.

screenshot of the user interface for the groundwater quality mapper
March 25, 2020

The GAMA-PBP Public-Supply Well Results data viewer allows the user to visualize and download California water-quality data and trends for1974 - 2014. Groundwater-quality data for 38 inorganic constituents are captured and can be downloaded for individual sites or by grid cell. 

Bathymetry of Monterey Canyon and the Soquel Canyon tributary
February 28, 2020

The California Seafloor Mapping Program (CSMP) is a cooperative program to create a comprehensive coastal and marine geologic and habitat base map series for California's State waters. Initiated in 2008, the CSMP has collected bathymetry and backscatter data that are being turned into habitat and geologic base maps.

Map of California showing the sections of the coast where the USGS has generated computer models of storm impacts.
February 28, 2020

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. Several versions of CoSMoS have been implemented for areas of the California coast.

scrublands with hills in the background
February 21, 2020

A portal for easy access to USGS data collected during hydrogeologic research projects in Anza Valley, CA

maps of Anza Valley, CA comparing land use in 1934 to 2005
February 21, 2020

Compares Anza Valley, CA land use data within the USGS study boundaries for 5 time periods between 1934 and 2005.

map of California shaded by GAMA deep aquifer study units
June 18, 2019

The GAMA program is a comprehensive statewide assessment designed to help better understand and identify risks to groundwater resources. Groundwater is sampled at many locations across California in order to characterize its constituents and identify trends in groundwater quality. The results of these tests provide information for water agencies to address a variety of water resource issues.

map of California shaded by GAMA shallow aquifer study units
June 18, 2019

n 2012, the Groundwater Ambient Monitoring & Assessment Priority Basin Project (GAMA-PBP) began water-quality assessments of shallow aquifers, which are typically used for private domestic and small system drinking-water supplies. GAMA-PBP is designed to identify where and to what extent water quality of groundwater aquifers meets benchmarks that have been established for drinking water.

maps of the 5 coastal drainage basins in San Diego County
May 16, 2019

Coastal Basins of San Diego County, California, and Northern Baja California, Mexico.  Local features include the San Dieguito River Basin, San Diego River Basin, Sweetwater River Basin, and Otay River Basin.  Maps also display locations of groundwater-monitoring sites. 

Filter Total Items: 334
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Year Published: 2020

2018 U.S. Geological Survey–California Geological Survey fault-imaging surveys across the Hollywood and Santa Monica Faults, Los Angeles County, California

We acquired multiple types of seismic data across the Hollywood Fault in Hollywood, Calif., and the Santa Monica Fault in Beverly Hills, Calif., in May and June 2018. On the basis of our data, we infer near-surface locations of various traces of these faults.From two separate profiles across the Hollywood Fault, we evaluated multiple seismic...

Catchings, Rufus D.; Hernandez, Janis; Goldman, Mark R.; Chan, Joanne H.; Sickler, Robert R.; Olson, Brian; Criley, Coyn J.
Catchings, R.D., Hernandez, J., Goldman, M.R., Chan, J.H., Sickler, R.R., Olson, B., and Criley, C.J., 2020, 2018 U.S. Geological Survey–California Geological Survey fault-imaging surveys across the Hollywood and Santa Monica Faults, Los Angeles County, California: U.S. Geological Survey Open-File Report 2020–1049, 42 p., https://doi.org/10.3133/ofr20201049.

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Year Published: 2020

Science plan for improving three-dimensional seismic velocity models in the San Francisco Bay region, 2019–24

This five-year science plan outlines short-term and long-term goals for improving three-dimensional seismic velocity models in the greater San Francisco Bay region as well as how to foster a community effort in reaching those goals. The short-term goals focus on improving the current U.S. Geological Survey San Francisco Bay region geologic and...

Aagaard, Brad T.; Graymer, Russell W.; Thurber, Clifford H.; Rodgers, Arthur J.; Taira, Taka'aki; Catchings, Rufus D.; Goulet, Christine A.; Plesch, Andreas
Aagaard, B.T., Graymer, R.W., Thurber, C.H., Rodgers, A.J., Taira, T., Catchings, R.D., Goulet, C.A., and Plesch, A., 2020, Science plan for improving three-dimensional seismic velocity models in the San Francisco Bay region, 2019–24: U.S. Geological Survey Open-File Report 2020–1019, 37 p., https://doi.org/10.3133/ofr20201019.

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Year Published: 2020

Operational earthquake forecasting during the 2019 Ridgecrest, California, earthquake sequence with the UCERF3-ETAS model

The first Uniform California Earthquake Rupture Forecast, Version 3–epidemic‐type aftershock sequence (UCERF3‐ETAS) aftershock simulations were running on a high‐performance computing cluster within 33 min of the 4 July 2019 M 6.4 Searles Valley earthquake. UCERF3‐ETAS, an extension of the third Uniform California Earthquake Rupture Forecast (...

Milner, Kevin R.; Field, Edward H.; Savran, William H; Page, Morgan T.; Jordan, Thomas H

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Year Published: 2020

A high-resolution seismic catalog for the initial 2019 Ridgecrest Earthquake sequence: Foreshocks, aftershocks, and faulting complexity

I use template matching and precise relative relocation techniques to develop a high-resolution earthquake catalog for the initial portion of the 2019 Ridgecrest earthquake sequence, from July 4-16, encompassing the foreshock sequence and the first 10+ days of aftershocks following the Mw 7.1 mainshock. Using 13,525 routinely cataloged events as...

Shelly, David R.

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Year Published: 2020

Caltech/USGS Southern California Seismic Network (SCSN) and Southern California Earthquake Data Center (SCEDC): Data availability for the 2019 Ridgecrest sequence

The 2019 M6.4 and M7.1 Ridgecrest earthquake sequence occurred in the eastern California shear zone (ECSZ). The mainshock ruptured the Little Lake fault zone and aftershocks extended from the Garlock fault in the south, to the southern end of the 1872 M7.5 Owens Valley earthquake rupture in the north. We present data from the Southern California...

Hauksson, Egill; Yoon, Clara; Yu, Ellen; Andrews, Jennifer; Alvarez, Mark; Bhadha, Rayo; Thomas, Valerie

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Year Published: 2020

Using a dense seismic array to determine structure and site effects of the Two Towers earthflow in northern California

We deployed a network of 68 three-component geophones on the slow moving Two Towers earthflow in northern California. We compute horizontal-to-vertical spectral ratios (HVSRs) from the ambient seismic field. The HVSRs have two prominent peaks, one near 1.23 Hz and another between 4 and 8 Hz at most stations. The 1.23 Hz resonance is a property...

Thomas, Amanda M.; Spica, Zack; Bodmer, Miles; Schulz, William; Roering, Joshua J.

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Year Published: 2020

U.S. Geological Survey Earthquake Science Center

The mission of the U.S. Geological Survey (USGS) Earthquake Science Center is to collect a wide range of data on earthquakes, faults, and crustal deformation; conduct research to increase our understanding of earthquake source processes, occurrence, and effects; and synthesize this knowledge into probabilistic seismic hazard assessments,...

Hickman, Stephen H.
This publication is available at https://pubs.er.usgs.gov/publication/fs20193067. After the Digital Object Identifier and product metadata have been registered by Crossref, the official URL will be https://doi.org/10.3133/fs20193067.

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Year Published: 2019

Seismic evaluation of shallow-depth structure, faulting, and groundwater variations across the Dos Palmas Preserve, Riverside County, California

IntroductionDos Palmas Preserve is a Colorado Desert oasis and wetland in Riverside County, California, located near the base of the Orocopia Mountains and northeast of the Salton Sea. The original source of water for the oasis was artesian springs that developed at the base of the Orocopia Mountains, but more abundant water supplies were later...

Catchings, Rufus D.; Goldman, Mark R.; Chan, Joanne H.; Sickler, Robert R.; Rymer, Michael J.; Criley, Coyn J.
Catchings, R.D., Goldman, M.R., Chan, J.H., Sickler, R.R., Rymer, M.J., and Criley, C.J., 2020, Seismic evaluation of shallow-depth structure, faulting, and groundwater variations across the Dos Palmas Preserve, Riverside County, California: U.S. Geological Survey Open-File Report 2019–1130, 21 p., https://doi.org/ 10.3133/ofr20191130.

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Year Published: 2019

Simple metrics predict salt-marsh sediment fluxes

The growth (or decay) of salt marshes depends on suspended-sediment flux into and out of the marsh. Suspended-sediment concentration (SSC) is a key element of the flux, and SSC-based metrics reflect the long-term sediment-flux trajectories of a variety of salt marshes. One metric, the flood–ebb SSC differential, correlates with area-normalized...

Nowacki, Daniel J. ; Ganju, Neil Kamal

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Year Published: 2019

A multidisciplinary coastal vulnerability assessment for local government focused on ecosystems, Santa Barbara area, California

Incorporating coastal ecosystems in climate adaptation planning is needed to maintain the well-being of both natural and human systems. Our vulnerability study uses a multidisciplinary approach to evaluate climate change vulnerability of an urbanized coastal community that could serve as a model approach for communities worldwide, particularly in...

Myers, Monique; Barnard, Patrick L.; Beighley, Edward; Cayan, Daniel R.; Dugan, Jenifer E.; Feng, Dongmei; Iacobellis, Samuel F.; Melack, John M.; Page, Henry M.

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Year Published: 2019

Sediment and organic carbon transport and deposition driven by internal tides along Monterey Canyon, offshore California

Submarine canyons provide globally important conduits for sediment and organic carbon transport into the deep-sea. Using a novel dataset from Monterey Canyon, offshore central California, that includes an extensive array of water column sampling devices, we address how fine-grained sediment and organic carbon are transported, mixed, fractionated,...

Maier, Katherine L.; Rosenberger, Kurt J.; Paull, Charles K.; Gwiazda, Roberto; Gales, Jenny; Lorenson, Thomas; Barry, James P.; Talling, Peter J.; McGann, Mary; Xu, Jingping; Lundsten, Eve M.; Anderson, Krystle; Litvin, Steven; Parsons, Daniel; Clare, Michael; Simmons, Stephen; Sumner, Esther J; Cartigny, Matthieu J.B.

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Year Published: 2019

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

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

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

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One-Water Hydrologic Flow Model cross section
April 7, 2020

The MODLFOW One-Water Hydrologic Flow Model (MF-OWHM) (MF-OWHM; Boyce and others, 2020Hanson and others, 2014) is a MODFLOW-2005-based integrated hydrologic flow model (IHM) that is the most complete version, to date, of the MODFLOW family of hydrologic simulators needed for the analysis of a broad range of conjunctive-use issues. 

Screenshot of GAMACTT web application.
January 24, 2020

Use this Groundwater Age Mixtures and Contaminant Trends Tool (GAMACTT) to explore the effects of basic aquifer properties and well configurations on groundwater age mixtures in groundwater discharge and on contaminant trends from varying nonpoint-source contaminant input scenarios.

4 graphs displaying example output from the TracerLPM software
January 15, 2020

An Excel® Workbook for Interpreting Groundwater Age Distributions from Environmental Tracer Data

multicolored map of Ocean Shores, Washington
April 13, 2017

The Pedestrian Evacuation Analyst is an ArcGIS extension that estimates how long it would take for someone to travel on foot out of a hazardous area that was threatened by a sudden event such as a tsunami, flash flood, or volcanic lahar. It takes into account the elevation changes and the different types of landcover that a person would encounter along the way.

MODPATH-OBS_distance-direction-observations_USGS-hydrologic-modelling
April 26, 2013

The MODPATH-OBS (Hanson and others, 2013) computer program is designed to calculate simulated equivalents for observations related to advective groundwater transport that can be represented in a quantitative way by using simulated particle-tracking data. 

map of the central valley with the CVHM grid cells overlaid, and a cross section of the subsurface
August 27, 2012

The Central Valley Hydrologic Model (CVHM) is an extensive, detailed three-dimensional (3D) computer model of the hydrologic system of the Central Valley (Faunt, 2009). The Central Valley Hydrologic Model (CVHM) simultaneously accounts for changing water supply and demand across the landscape, and simulates surface water and groundwater flow across the entire Central Valley.

subsurface grid showing relationship surface water and groundwater recharge
June 19, 2008

A Grid-Based, Distributed-Parameter Watershed Model to Estimate Net Infiltration Below the Root Zone

Filter Total Items: 1,175
February 27, 2020

PubTalk 2/2020 — From California to Cambodia

From California to Cambodia - Surface Water Mapping Using Cloud-Based Remote Sensing (by Christopher Soulard, USGS Research Geographer)

  • With cloud based remote sensing we can now access, process, and analyze terabytes of satellite imagery remotely via the internet.
  • Satellite images and streamgages are the two most common measurement tools used to
Attribution: Science Support
A group of six photographs showing equipment used for collecting data in the field.
February 24, 2020

Field equipment for bathymetric and topographic surveys

Field equipment used by USGS Pacific Coastal and Marine Science Center scientists for bathymetric and topographic surveys in the Sacramento-San Joaquin Delta, California

maps of Anza Valley, CA comparing land use in 1934 to 2005
February 14, 2020

Land Use Change (1934 - 2005), Anza Valley, CA

Land use change in the Anza Valley, CA from 1934 to 2005.  

Green background flyer with images of birds near fields and flooding with boats.
February 10, 2020

2020 February Public Lecture Flyer

2020 February Public Lecture Flyer

From California to Cambodia - Surface Water Mapping Using Cloud-Based Remote Sensing

By Chris Soulard, USGS Western Geographic Science Center

  • With cloud based remote sensing we can now access, process, and analyze terabytes of satellite imagery remotely via the internet. 
  • Satellite
...
Photo of complex equipment on mud tank, including pipes, shaker screens, and other mud-spattered equipment.
January 31, 2020

Mud tank and shakers during groundwater well drilling

Ever wondered about how groundwater observation wells are drilled? This photo provides a behind-the-scenes look as USGS drilled a groundwater well in California last month. This photo looks down over a mud tank and shakers, which are part of drilling operations. The drillers pump clean mud from the tank down the hole as they drill; this mud plays an important role in

...
Attribution: Water Resources
January 23, 2020

PubTalk 1/2020 — The Rise of the USGS in Space Exploration

The Rise of the USGS in Space Exploration: How the Astrogeology Science Center is integral to the past, present, and future investigation of the Solar System.

By Justin J. Hagerty, Director of the Astrogeology Science Center

  • Every astronaut to set foot on the Moon trained with the USGS in
A boat floats on calm waters with some people sitting in it.
January 22, 2020

Sampling on Grizzly Bay

A team of USGS scientists afloat on Grizzly Bay, a baylet of San Francisco Bay in Solano County, California. USGS collects sediment samples to study how sediment moves through sensitive coastal environments like this.

A photograph shows a boat sitting at a dock, with tall grasses in the foreground and the setting sun in the distance.
January 22, 2020

Preparing for a day of sampling in Grizzly Bay

Scientists from the USGS Pacific Coastal and Marine Science Center docked at Belden's Landing Water Access Facility on Montezuma Slough. They are preparing for a day of sampling in Grizzly Bay, where they study how sediment moves through sensitive coastal environments.

People sit in a small boat floating the water, preparing a sampling device to collect sediment from the bottom of the water.
January 22, 2020

Preparing the GOMEX in Grizzly Bay

From left to right, USGS scientists Sam McGill, Lucas WinklerPrins, David Hart, Selina Davila Olivera, and Pete Dal Ferro work on Grizzly Bay to collect sediment samples using the GOMEX box corer.

Illustration of a bay and delta region with different colors to depict varying depths of water.
January 17, 2020

Bathymetric map of the northern portion of San Francisco Bay (MLLW)

Digital elevation model (DEM) of northern San Francisco Bay, California, created using bathymetry data collected between 1999 and 2016 (MLLW)

Earthquakes at Long Valley Caldera 1984 to present
December 31, 2019

Earthquakes at Long Valley Caldera 1984 to present

The vertical bars on the graphs below correspond with the left-side y-axis and represent the number of earthquakes per day. The red line indicates the cumulative number of earthquakes and corresponds with the right-side y-axis. Earthquake swarms occurred at Long Valley from 1978-1983, 1990-1995, 1996, and 1997-1998. The rate of earthquakes since the end of the last swarm 

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

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

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

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

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

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

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

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

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

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

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

California Volcano Observatory emblem
March 24, 2020

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

person on a gravel road along side a row of wind turbines
March 13, 2020

A comprehensive analysis of how renewable energy facilities affect wildlife could inform efforts to predict and reduce these impacts. A team of researchers was asked to gain a better understanding of the actual environmental impacts of renewable energy generation on sensitive species and habitats in California. 

Map of San Antonio Reservoir and Watershed, California
January 23, 2020

In two recent publications, California Water Science Center scientists discuss their research using acoustic and optic technology to measure the quantity and movement of sediment in rivers and reservoirs.

two women making measurements of a rupture in the ground surface
January 23, 2020

The 2019 Ridgecrest earthquake sequence, which startled nearby California residents over the 4 July holiday with magnitude 6.4 and magnitude 7.1 earthquakes, included 34,091 earthquakes overall, detailed in a high-resolution catalog created for the sequence.

Read SSA News Release

Satellite imagery of the December 2019 low flying survey looking at geology, hydrology and natural resources of the region
December 5, 2019

For about two months, starting around December 7, 2019, an airplane operated under contract to the USGS will be making low-level flights over parts of the eastern Mojave Desert.

Dr. Barnard
December 5, 2019

Briefing held on science and policy initiatives that are helping protect West Coast ecosystems and communities from erosion, sea level rise, and other coastal hazards.

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