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

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: January 21, 2021

Mapping Challenge Update (01/21/21): City / Town Halls in CA & NV

Volunteers continue to make headway on this challenge with another 40 points added since last week.  However, there are a handful of communities in the metropolitan areas that still need a point. See our spatial analyses for tips on which communities these may be. 

Date published: January 14, 2021

Mapping Challenge Update (01/14/21): City / Town Halls in CA & NV

Volunteers jumped in feet first with almost 30 new points added since last week. That's pretty good, considering volunteers need to sift through what's already on the map versus what still needs to be collected.  Keep up the good work!!  

Date published: January 7, 2021

NEW TNMCorps Mapping Challenge for City / Town Halls in CA & NV!

TNMCorps Mapping Challenges shift to the Pacific Coast with a new challenge for city/town halls in California and Nevada. Just in time to help fend off those winter blues, too!

Filter Total Items: 410
Date published: January 20, 2021
Status: Active

Assessing Sediment Nutrient Storage and Release in California's Sacramento-San Joaquin Delta

Sediments represent an important pool of nutrients in the Sacramento-San Joaquin Delta (Delta). The exchange of nutrients between the water column and the benthos impacts water quality and effects phytoplankton, harmful algal blooms, aquatic vegetation, and drinking water quality. To date, there is very limited information about nutrient pools in Delta sediments, nor how these nutrients are...

Date published: December 31, 2020
Status: Active

San Francisco Bay geomorphology

This research is part of the project “Sediment Transport in Coastal Environments

Contacts: Bruce Jaffe
Date published: December 31, 2020
Status: Active

Drag and sediment transport: conditions at the bottom boundary

Research on bed sediment grain size, bedform morphology, vegetation characteristics, and sediment resuspension and transport is part of the Sediment Transport in Coastal Environments project.

Contacts: Jessie Lacy
Date published: December 16, 2020
Status: Active

2013 Springs Fire, Ventura County, California Landslide Monitoring Site

Recent Monitoring Data

Date published: December 16, 2020
Status: Active

U.S. Highway 50, CA Landslide Monitoring Site

Recent Monitoring Data

Date published: December 15, 2020
Status: Active

San Francisco Bay Area - Pacifica, CA (BALT4) Landslide Monitoring Site

Recent Monitoring Data

Date published: December 15, 2020
Status: Active

San Francisco Bay Area - Brisbane, CA (BALT3) Landslide Monitoring Site

Recent Monitoring Data

Date published: December 15, 2020
Status: Active

San Francisco Bay Area - Brisbane, CA (BALT3) Landslide Monitoring Site

Recent Monitoring Data

Date published: November 24, 2020
Status: Active

2009 Station Fire, Dunsmore Canyon, Glendale, California

Recent Monitoring Data

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Date published: January 26, 2021

Hydrodynamic and sediment transport data from San Pablo Bay and Grizzly Bay, California, 2019

USGS scientists collected hydrodynamic and sediment-transport data at shallow water sites in San Pablo Bay and Grizzly Bay, in northern San Francisco Bay between June and November 2019. The data were collected to determine hydrodynamic forcing, bed roughness, suspended-sediment concentration, and physical properties of the sediment bed. This data release includes hydrodynamic and sediment...

Date published: January 21, 2021

Hydrogeology of the Adelaida Area, San Luis Obispo County, CA

The USGS is conducting a comprehensive evaluation of groundwater resources of the Adelaida area. Use this map to explore the hydrogeology of the area, including land use, geology, and USGS hydrologic data by watershed or water management district. 

Date published: December 31, 2020

California shorelines and shoreline change data, 1998-2016

Mean high water shorelines along the coast of California for the years 1998-2002, 2015, and 2016 were extracted from LiDAR digital elevation models using ArcGIS. The Digital Shoreline Analysis System was used to calculate net shoreline movement between the pre-El Niño and post-El Niño shorelines, as a proxy for sandy shoreline change throughout the El Niño winter season. For a longer-term...

Date published: December 31, 2020

Pilot study on bathymetric change analyses in the Sacramento-San Joaquin Delta, California

This pilot study explores historic bathymetric change in the Delta. The earliest comprehensive surveys that covered a large portion of the Delta were conducted in the 1930s. These historic surveys are compared to recent surveys to document how sedimentation and erosion have changed the Delta. We selected regions for the pilot study based on availability of data, critical habitats, and...

Date published: December 28, 2020

California Groundwater Ambient Monitoring and Assessment (GAMA) Program Shallow Aquifer Assessment Study Unit Boundaries and Grid Cells for Assessment of Groundwater Resources

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

Date published: December 28, 2020

Zooplankton Survey of the Northern Sacramento-San Joaquin Delta, California, 2016-2018

This data set contains information on zooplankton and associated environmental parameters for sampling conducted in California's northern Sacramento-San Joaquin Delta between May 2016 and April 2018. Macrozooplankton were sampled with horizontal tows (water surface) of a 50 cm-diameter conical plankton net that was 150cm long with 102µm mesh. Samples were preserved in the field in 10%

Date published: December 28, 2020

California Groundwater Ambient Monitoring and Assessment (GAMA) Program Shallow Aquifer Assessment Study Unit Boundaries and Grid Cells for Assessment of Groundwater Resources

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

Date published: December 22, 2020

Potential Explanatory Factors for Groundwater Quality in the Northern Sierra Nevada Foothills Domestic-Aquifer Assessment Study Units, 2015-2017: California GAMA Priority Basin Project

This data release codifies and attributes explanatory factors that could potentially impact groundwater quality at 142 groundwater sites (wells or developed springs) used for domestic water supply and 310 groundwater sites used for public water supply in the northern Sierra Nevada foothills. Water quality from domestic groundwater sites was assessed as part of the California State Water Resou...

Date published: November 25, 2020

Aquifer test data for the Belridge multiple-well monitoring site (BWSD), Kern County, California

To determine aquifer characteristics, pneumatic slug tests were performed on selected zones and aquifers at a monitoring site near the North and South Belridge oil fields in the Southern San Joaquin Valley in Kern County. On November 19th and 20th, 2018, pneumatic slug tests were performed at five monitoring wells located at the multiple-well groundwater-monitoring site BWSD (28S/21E-08

Date published: November 4, 2020

Bathymetry and acoustic backscatter data collected in 2008 offshore Tijuana River Estuary, California during USGS Field Activity S-5-08-SC

In 2008 the USGS collected bathymetry and acoustic-backscatter data offshore the Tijuana River Estuary, California. Mapping was conducted as part of the Tijuana Estuary Fine Sediment Fate and Transport Demonstration Project, which was developed by a number of State of California, federal, and private industry partners to provide information about the directions, rates, and processes of fine...

Date published: October 27, 2020

Electron microprobe analyses of hydrothermal muscovite crystals from gold-bearing quartz veins of the Klamath Mountains, California, 2014 and 2019

This data release provides geochemical results of in situ electron probe microanalyses of hydrothermal muscovite associated with gold-bearing quartz veins from the Klamath Mountains, California. Samples were collected from eight different mines in the summer of 2013 and electron probe microanalyses were carried out May 27, 2014 and November 12, 2019.

Date published: September 8, 2020

Assessment of water-quality in the California Sacramento-San Joaquin Delta during a North Delta directed flow action: August - October 2018

This report documents the spatial and temporal variability of nutrients and related water quality parameters at high spatial resolution in the North Delta in the Sacramento-San Joaquin River Delta of California, USA. The data set includes nitrate, ammonium, phosphate, dissolved organic carbon, temperature, conductivity, dissolved oxygen, turbidity, and chlorophyll . Data-collect

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View of Capitola, California, coastline
January 26, 2021

Prediction of Flooding Now and Into the Future: a geonarrative on coastal storms

map excerpt displaying geology
January 21, 2021

The USGS is conducting a comprehensive evaluation of groundwater resources of the Adelaida area. Use this map to explore the hydrogeology of the area, including land use, geology, and USGS hydrologic data by watershed or water management district. 

nightly view of highway with large cracks from earthquake and car in the distance.
December 4, 2020

This USGS geonarrative (Esri Story Map) summarizes the USGS response and findings after the M6.4 on July 4 and M7.1 on July 6, 2019 in Searles Valley, Southern California, and includes links to USGS research publications and data releases.

bluegreen algae distribution map
August 7, 2020

A data visualization exploring the relationship between nutrient distribution and phytoplankton under different conditions across the San Francisco Delta and Estuary. Assessing distribution and abundance aids understanding of how managing nutrient supplies affects aquatic food webs, helping managers evaluate the potential environmental benefits of future nutrient reduction efforts against costs.

screen shot of Bay-Delta web app that visualizes water quality data
August 6, 2020

Data visualization tool created for California's Bay-Delta Regional Monitoring Program.  This web application visualizes nutrients and phytoplankton spatially and temporally for data collected in 2018.

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. 

Figure 4 for Southwestern Willow Flycatcher Habitat Viewer webpage
March 12, 2020

Figure 4. Yearly Distribution (2007-2019) of Tamarisk Beetle (Diorhabda spp.). Annual tamarisk beetle distribution map. Provided by RiversEdge West. 2020. Used with permission from Ben Bloodgood, Program Coordinator.

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.

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Year Published: 2021

Toward physics-based nonergodic PSHA: A prototype fully-deterministic seismic hazard model for southern California

We present a nonergodic framework for probabilistic seismic‐hazard analysis (PSHA) that is constructed entirely of deterministic, physical models. The use of deterministic ground‐motion simulations in PSHA calculations is not new (e.g., CyberShake), but prior studies relied on kinematic rupture generators to extend empirical earthquake rupture...

Milner, Kevin R.; Shaw, Bruce E.; Goulet, Christine A.; Richards-Dinger, Keith B.; Callaghan, Scott; Jordan, Thomas H.; Dieterich, James H.; Field, Edward H.

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Year Published: 2020

Characteristics of frequent dynamic triggering of microearthquakes in Southern California

Dynamic triggering of earthquakes has been reported at various fault systems. The triggered earthquakes are thought to be caused either directly by dynamic stress changes due to the passing seismic waves, or indirectly by other nonlinear processes that are initiated by the passing waves. Distinguishing these physical mechanisms is difficult...

Fan, Wenyuan; Barbour, Andrew; Cochran, Elizabeth S.; Lin, Guoqing

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Year Published: 2020

Characterizing strain between rigid crustal blocks in the southern Cascadia forearc: Quaternary faults and folds of the northern Sacramento Valley, California

Topographic profiles across late Quaternary surfaces in the northern Sacramento Valley (California, USA) show offset and progressive folding on series of active east- and northeast—trending faults and folds. Optically stimulated luminescence ages on deposits draping a warped late Pleistocene river terrace yielded differential incision rates along...

Angster, Stephen J.; Wesnousky, Steven G.; Figueiredo, Paula; Owen, Lewis A.; Sawyer, Thomas

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Year Published: 2020

Seismic attenuation monitoring of a critically stressed San Andreas fault

We show that seismic attenuation ( ) along the San Andreas fault (SAF) at Parkfield correlates with the occurrence of moderate‐to‐large earthquakes at local and regional distances. Earthquake‐related  anomalies are likely caused by changes in permeability from dilatant static stress changes, damage by strong shaking from local...

Malagnini, Luca; Parsons, Thomas E.

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Year Published: 2020

Localized fault-zone dilatancy and surface inelasticity of the 2019 Ridgecrest earthquakes

Earthquakes produce a spectrum of elastic and inelastic deformation processes that are reflected across various length and time scales. While elasticity has long dominated research assumptions in active tectonics, increasing interest has focused on the inelastic characteristics of earthquakes, particularly those of the surface fault rupture zone...

Barnhart, William D.; Gold, Ryan D.; Hollingsworth, James

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Year Published: 2020

Seismic reflection imaging of the low-angle Panamint normal fault system, eastern California

Shallowly dipping (<30°) low‐angle normal faults (LANFs) have been documented globally; however, examples of active LANFs in continental settings are limited. The western margin of the Panamint Range in eastern California is defined by a LANF that dips west beneath Panamint Valley and has evidence of Quaternary motion. In addition, high‐angle...

Gold, Ryan D.; Stephenson, William J.; Briggs, Richard W.; Duross, Christopher; Kirby, Eric; Woolery, Edward W; Delano, Jaime; Odum, Jackson K.

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Year Published: 2020

Developing post-alert messaging for ShakeAlert, the earthquake early warning system for the West Coast of the United States of America

As ShakeAlert, the earthquake early warning system for the West Coast of the U.S., begins its transition to operational public alerting, we explore how post-alert messaging might represent system performance. Planned post-alert messaging can provide timely, crucial information to both emergency managers and ShakeAlert operators as well as...

McBride, Sara; Bostrom, Ann; Sutton, Jeannette; deGroot, Robert Michael; Baltay, Annemarie S.; Terbush, Brian; Bodin, Paul; Dixon, Maximilian; Holland, Emily; Arba, Ryan; Laustsen, Paul C.; Liu, Sophia; Vinci, Margaret

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Year Published: 2020

Increasing threat of coastal groundwater hazards from sea-level rise in California

Projected sea-level rise will raise coastal water tables, resulting in groundwater hazards that threaten shallow infrastructure and coastal ecosystem resilience. Here we model a range of sea-level rise scenarios to assess the responses of water tables across the diverse topography and climates of the California coast. With 1 m of sea-level rise,...

Befus, K.M.; Barnard, Patrick L.; Hoover, Daniel J.; Finzi Hart, Juliette; Voss, Clifford I.

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Year Published: 2020

A stress-similarity triggering model for aftershocks of the MW6.4 and MW7.1 Ridgecrest earthquakes

The July 2019 Mw">Mw 6.4 and 7.1 Ridgecrest earthquakes triggered numerous aftershocks, including clusters of off‐fault aftershocks in an extensional stepover of the Garlock fault, near the town of Olancha, and near Panamint Valley. The locations of the off‐fault aftershocks are consistent with the stress‐similarity model of triggering,...

Hardebeck, Jeanne L.

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Year Published: 2020

Evidence of previous faulting along the 2019 Ridgecrest, California earthquake ruptures

The July 2019 Ridgecrest earthquake sequence in southeastern California was characterized as surprising because only ~35% of the rupture occurred on previously mapped faults. Employing more detailed inspection of pre-event high-resolution topography and imagery in combination with field observations, we document evidence of active faulting in the...

Thompson Jobe, Jessica; Philibosian, Belle; Chupik, Colin; Dawson, Timothy E.; Bennett, Scott E. K.; Gold, Ryan D.; Duross, Christopher; Ladinsky, Tyler C.; Kendrick, Katherine; Haddon, Elizabeth; Pierce, Ian; Swanson, Brian J.; Seitz, Gordon G.

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Year Published: 2020

Human behavioral response in the Ridgecrest earthquakes: Assessing immediate actions based on data from “Did You Feel It?”

Human behavioral response to earthquake ground motion has long been a subject of multidisciplinary interest and research. In most versions of seismic intensity scales, human perceptions and behavior are one component of the assignment of intensity. Public health research has shown that actions taken during earthquakes have a significant impact on...

Goltz, James D.; Park, Hyejeong; Quitoriano, Vince; Wald, David J.

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Year Published: 2020

The predictive skills of elastic Coulomb rate-and-state aftershock forecasts during the 2019 Ridgecrest, California, earthquake sequence

Operational earthquake forecasting protocols commonly use statistical models for their recognized ease of implementation and robustness in describing the short-term spatiotemporal patterns of triggered seismicity. However, recent advances on physics-based aftershock forecasting reveal comparable performance to the standard statistical counterparts...

Mancini, Simone; Segou, Margarita; Werner, Maximillian J; Parsons, Thomas E.

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Image of a coastal cliff with lines drawn on it, that help to define the shape and areas of weakness.
August 19, 2020

The Cliff Feature Delineation Tool scans digital elevation models (DEM) to delineate features on seacliffs like the cliff top, midline, toe, and convexities/concavities on the cliff face, outputting linear features as polylines and point shapefiles. 

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

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Steam vents along the Yellowstone River near Mud Volcano thermal area
January 12, 2021

Steam vents along the Yellowstone River near Mud Volcano thermal area

Steam vents along the Yellowstone River near Mud Volcano thermal area, Yellowstone National Park.

donut charts comparing irrigated land use in the Adelaida Area of San Luis Obisbo County, CA for 1984, 1996, 2004, 2014 and 2016
January 8, 2021

Irrigated Land Use, Adelaida Area, San Luis Obispo County, CA

Irrigated land-use in the Adelaida Area of San Luis Obisbo County, CA for 1984, 1996, 2004, 2014, and 2016. Numbers indicate acres and percent of total acres. Source: California Department of  Conservation Farmland Mapping and Monitoring Program, 

...
layered bar chart displaying number and percent of total acres used for a variety of agriculture categories for 1996 and 2014
January 7, 2021

Land Use (1996 and 2014), San Luis Obisbo County, CA

Land-use surveys of the Adelaida Area of San Luis Obisbo County, CA for 1996 and 2014. Numbers indicate acres and percent of total developed acres. Source: California Department of Water Resources, 

...
A dark image looking down from a vegetated coastal bluff at a sandy beach and the ocean.
November 19, 2020

Sunset State Beach Variance Image

Far out, man... where science meets art

This is an image produced from one of two video cameras, which were installed to overlook the coast at Sunset State Beach in Watsonville, California. The cameras are part of the USGS Pacific Coastal and Marine Science Center’s 

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A man wearing safety gear and a warm hat sits in a pontoon boat in very calm water setting up equipment, bridge in background.
September 29, 2020

Portable single-beam echo sounder set-up

Marine engineering technician Pete Dal Ferro sets up a newly acquired, portable, single-beam echo sounder on the San Lorenzo River in Santa Cruz, California. The new device, called CEESCOPE, collects bathymetric (depth) data and also records features of the subsurface. All the components are easy for one person to set up and operate, with GPS and an LCD touch screen. This

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A small inflatable boat sits on a towing platform with big wheels, on sand in front of an elevated amusement park ride.
September 29, 2020

Ready for nearshore survey

The USGS Pacific Coastal and Marine Science Center's new inflatable boat equipped with a portable, single beam, shallow-water echo sounder used for nearshore surveys. USGS scientists collect such data seasonally, to study sediment input and movement in and around Monterey Bay area beaches.

Click on image for full description.
September 16, 2020

GeoDAWN: Geoscience Data Acquisition for Western Nevada

The USGS Earth Mapping Resources Initiative and USGS 3D Elevation Program (3DEP), Department of Energy Geothermal Technologies Office, Natural Resources Conservation Services, and Bureau of Land Management have partnered to conduct airborne geophysical and 3DEP lidar surveys over parts of Nevada and California to collect information on undiscovered geothermal, critical

...
September 11, 2020

Image of the Week - Summer Fires Rage in California

As fire season continues in the western United States let's look back at a number of incidents tracked by officials across California in August. These fires were captured during the day by Landsats 7 and 8, in natural color bands of the visible spectrum. Landsat sensors also record infrared wavelengths revealing burn scars and active fires. Natural color images show smoke

A map illustration of the seafloor off of a coastal area, that shows the features like submarine canyons and depth.
August 14, 2020

Offshore northern California bathymetric map

Bathymetric map of offshore northern California reveals seafloor features and submarine canyons.

A map shows relief of a long stretch of continental margin with features on land and in the ocean labeled with lines and words.
August 14, 2020

Cascadia megathrust fault map

Topo-bathymetric map of the Cascadia subduction zone. Cascadia megathrust fault (white line); approximate shelf break along 200-m isobath (yellow line); MTJ, Mendocino triple junction.

Map illustration of the seafloor off the continental coastline shows all of the regions and tracklines of recent fieldwork.
August 14, 2020

Cascadia fieldwork map

Index map of U.S. Cascadia margin showing where data have been collected since 2018 as part of the Subduction Zone Marine Geohazards Project. Details of each survey effort are provided on the Cascadia Subduction Zone Marine Geohazards project web site.

June 19, 2020

Remembering Ridgecrest

Reflections on the Ridgecrest earthquake sequence one year after from a few USGS employees. Employees discuss when they first heard about the magnitude 6.4 and notable professional experiences that happened afterwards.
 

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TNMCorps Mapping Challenge: City/Town Halls in CA & NV
January 21, 2021

Volunteers continue to make headway on this challenge with another 40 points added since last week.  However, there are a handful of communities in the metropolitan areas that still need a point. See our spatial analyses for tips on which communities these may be. 

TNMCorps Mapping Challenge: City/Town Halls in CA & NV
January 14, 2021

Volunteers jumped in feet first with almost 30 new points added since last week. That's pretty good, considering volunteers need to sift through what's already on the map versus what still needs to be collected.  Keep up the good work!!  

TNMCorps Mapping Challenge: City/Town Halls in CA & NV NEW
January 7, 2021

TNMCorps Mapping Challenges shift to the Pacific Coast with a new challenge for city/town halls in California and Nevada. Just in time to help fend off those winter blues, too!

nightly view of highway with large cracks from earthquake and car in the distance.
December 4, 2020

A new geonarrative (Esri Story Map) summarizes the USGS response and findings after the M6.4 on July 4 and M7.1 on July 6, 2019 in Searles Valley, Southern California.

Dots on map of United States show general locations where scientists recently conducted fieldwork.
November 30, 2020

Learn more about the recent field activities completed by scientists in the Coastal and Marine Hazards and Resources Program at the USGS, and explore the Science Projects that guide this fieldwork.

color photo of helicopter over fire
November 27, 2020

In his regular job, EROS Scientist Kurtis Nelson manages post-fire mapping activities at EROS—the largest being Monitoring Trends in Burn Severity, and the Department of Interior’s (DOI) Burned Area Emergency Response (BAER) support. But for 21 days this past August and September, he did something more.

Colored, shaded-relief terrain map of Brushy Butte Volcano
November 12, 2020

The U.S. Geological Survey (USGS) has 5 volcano observatories tasked with monitoring low to high threat volcanoes throughout the United States. 

Newly formed wetland that formed as the Salton Sea level lowers
November 5, 2020

In the past decade, Salton Sea water elevation has declined due to drought, lining of canals, and changes to management of the Colorado River. This has resulted in the creation of new wetlands caused by drains and rivers no longer reaching the Salton Sea.

map of swarm area showing earthquakes as circles
September 30, 2020

A swarm of earthquakes southeast of the Salton Sea, in the Brawley seismic zone, began on Sept. 30, 2020.

Forecast last updated October 7, 2020 at 8:00am PDT.

Two maps illustrate two states of computer modeling scenarios around a large bay and coastal area.
September 30, 2020

A new model that combines sea-level rise scenarios and information about associated groundwater level responses shows that coastal water tables will rise as groundwater levels are pushed up by landward intrusions of seawater due to sea-level rise.

Hells Canyon on the Snake River
September 28, 2020

SPARROW mappers are interactive tools that allow users to evaluate streamflow and nutrient and sediment conditions as well as the importance of different sources of contaminants in a selected river basin. Data can be visualized at different scales using maps and interactive graphs and tables.

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