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Filter Total Items: 358
USGS scientist collecting samples of aquatic species from the Pike River, Wis., for later analysis of mercury contamination.
Date Published: August 30, 2018
Status: Active

Microbial Biogeochemistry Laboratory — Menlo Park, California

About the Laboratory

Microbiologists at the Microbial Biogeochemistry Laboratory develop and apply innovative methods to measure key microbial processes. These methods are used to better understand how major biogeochemical cycles (carbon, nitrogen, sulfur, and iron) interact with and control the speciation and fate of metals like mercury and selenium which can impact...

Experimental laboratory setup to study uranium uptake by aquatic organisms
Date Published: August 29, 2018
Status: Active

Bio-Uptake Research Laboratory — Menlo Park, California

 

About the Laboratory

The Bio-Uptake Research Laboratory uses novel stable isotope tracing techniques to assess the bioavailability of inorganic contaminants and characterize the underlying processes governing their bioavailability.

Pollen samples from various plants collected from hedgerows
Date Published: August 28, 2018
Status: Active

Organic Chemistry Research Laboratory — Sacramento, California

About the Laboratory

Chemists and hydrologists at the Organic Chemistry Research Laboratory (OCRL) develop targeted analytical methods for the quantitation of chemicals that can impact the health of organisms and humans. They have developed methods in a wide variety of environmental media; in addition to water and sediment, they also analyze a variety of tissue matrices...

map of California shaded by potential increase in soil water holding capacity in inches
Date Published: August 27, 2018
Status: Completed

Increasing Soil Organic Carbon to Mitigate Greenhouse Gases and Increase Climate Resiliency for California

Rising air temperatures are projected to continue to drive up urban, agricultural, and rangeland water use, straining both surface and groundwater resources. Scientific studies have shown that managing farms, ranches, and public lands to increase soil carbon can increase soil waterholding capacity and increase hydrologic benefits such as increased baseflows and aquifer recharge, reduced...

Contacts: Michelle Stern
Photo #9 of well site YVDA being drilled
Date Published: August 24, 2018
Status: Active

Yucaipa Valley Hydrogeology

This study assesses the quality of water in the Yucaipa area, primarily in the Yucaipa plain. This hydrogeology study will aid local water purveyors in understanding and evaluating local resources and using those resources effectively in combination with water imported from northern California and from the adjacent San Bernardino area.

Contacts: Gregory Mendez
Cartoon shows a cylindrical object that is floating above and scanning a landscape with rocky outcroppings.
Date Published: August 7, 2018
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
Lorem ipsum dolor sit amet
Date Published: August 5, 2018
Status: Active

Global Hyperspectral Imaging Spectroscopy of Agricultural-Crops & Vegetation (GHISA)

This webpage showcases the key research advances made in hyperspectral remote sensing of agricultural crops and vegetation over the last 50 years. There are three focus areas:

A Critical Assessment of Recent Soil Dating Methods in Coastal Wetlands
Date Published: July 18, 2018
Status: Active

A Critical Assessment of Recent Soil Dating Methods in Coastal Wetlands- Judith Drexler

Are you interested in coastal wetlands and how they form in the landscape? In this internship you will learn about wetland formation and how carbon accumulates in wetland soils over time. In addition, you will learn to learn how to critically evaluate soil dating methods that are currently being used to report carbon accumulation to the US EPA and the Intergovernmental Panel on Climate Change...

Image: Tidal Marshland in the Plum Island Estuary, Massachusetts
Date Published: July 17, 2018
Status: Active

A tale of two coasts: tidal marsh persistence with changing climate and sea-level rise- Karen Thorne

The overall goal of this project is to improve our understanding of the combined effects of inundation, due to sea-level rise and storm surges, and other climate factor on tidal marsh physical and biological processes to provide guidance to natural resource managers to reduce these threats and increase resilience.

A Google Earth™ image showing the principal zone of faulting (in red) near the town of Healdsburg.
Date Published: July 16, 2018
Status: Completed

A New Map of Rodgers Creek Fault in Sonoma County, California

Release Date: JULY 16, 2018

A new more detailed and higher resolution map of the Rodgers Creek Fault in Sonoma County, California, has been produced using aerial photography and hillshade imagery derived from LiDAR data.

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: July 16, 2018
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
A building after an earthquake has crumbled the roof and brick walls, the interior is now visible.
Date Published: July 12, 2018
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...

Filter Total Items: 315
USGS
January 1, 2017

Maximum depth of flooding surface (in cm) in the region landward of the present day shoreline that is inundated for the storm condition and sea-level rise (SLR) scenario indicated. Note: Duration datasets may have occasional gaps in open-coast sections.
The Coastal Storm Modeling System (CoSMoS) makes detailed predictions (meter-scale) over large geographic scales (100s of kilometers) of storm-in

USGS
January 1, 2017

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 Southern California shows pr

USGS
January 1, 2017

Files contain hydrodynamic and sediment transport data for the location and deployment indicated. Time-series data of water depth, velocity, turbidity, and temperature were collected in San Pablo Bay and China Camp Marsh as part of the San Francisco Bay Marsh Sediment Experiments. Several instruments were deployed in tidal creek, marsh, mudflat, and Bay locations, gathering data on water depth, v

USGS
January 1, 2017

Geographic extent of projected coastal flooding, low-lying vulnerable areas, and maxium/minimum flood potential (flood uncertainty) associated with the sea-level rise 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

USGS
January 1, 2017

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 Southern California shows pr

USGS
January 1, 2017

Maximum depth of flooding surface (in cm) in the region landward of the present day shoreline that is inundated for the storm condition and sea-level rise (SLR) scenario indicated. Note: Duration datasets may have occasional gaps in open-coast sections.
The Coastal Storm Modeling System (CoSMoS) makes detailed predictions (meter-scale) over large geographic scales (100s of kilometers) of storm-in

USGS
January 1, 2017

Geographic extent of projected coastal flooding, low-lying vulnerable areas, and maxium/minimum flood potential (flood uncertainty) associated with the sea-level rise 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

USGS
January 1, 2017

Projected Hazard: Maximum depth of flooding surface (in cm) in the region landward of the present day shoreline that is inundated for the storm condition and sea-level rise (SLR) scenario indicated. Note: Duration datasets may have occasional gaps in open-coast sections.
Model Summary: The Coastal Storm Modeling System (CoSMoS) makes detailed predictions (meter-scale) over large geographic sca

USGS
January 1, 2017

Projected Hazard: Model-derived significant wave height (in meters) for the given storm condition and sea-level rise (SLR) scenario.
Model Summary: 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

USGS
January 1, 2017

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 Southern California shows pr

USGS
January 1, 2017

This part of DS 781 presents 2-m-resolution data for the acoustic-backscatter map of the Offshore of Point Conception Map Area, California. The GeoTiff is included in "Backscatter_OffshorePointConception.zip," which is accessible from https://doi.org/10.5066/F7QN64XQ. These data accompany the pamphlet and map sheets of Johnson, S.Y., Dartnell, P., Cochrane, G.R., Hartwell, S.R., Golden, N.E., Kvi

USGS
January 1, 2017

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 Southern California shows pr

Filter Total Items: 311
Publication Thumbnail
Year Published: 2006

Mineralogy and Morphology of Amphiboles Observed in Soils and Rocks in El Dorado Hills, California

From the Executive Summary: At the request of the U.S. Environmental Protection Agency (USEPA), the U.S. Geological Survey (USGS) has conducted an independent study of amphiboles in rocks and soils in the El Dorado Hills, California, area. The purpose of this study is to investigate specific issues regarding the presence of 'naturally occurring...

Meeker, G.P.; Lowers, H.A.; Swayze, G.A.; Van Gosen, B. S.; Sutley, S.J.; Brownfield, I.K.
Mineralogy and Morphology of Amphiboles Observed in Soils and Rocks in El Dorado Hills, California; 2006; OFR; 2006-1362; Meeker, G. P.; Lowers, H. A.; Swayze, G. A.; Van Gosen, B. S.; Sutley, S. J.; Brownfield, I. K.

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Year Published: 2006

Physical properties of two core samples from Well 34-9RD2 at the Coso geothermal field, California

The Coso geothermal field, located along the Eastern California Shear Zone, is composed of fractured granitic rocks above a shallow heat source. Temperatures exceed 640 ?F (~338 ?C) at a depth of less than 10000 feet (3 km). Permeability varies throughout the geothermal field due to the competing processes of alteration and mineral precipitation,...

Morrow, C.A.; Lockner, D.A.
Physical properties of two core samples from Well 34-9RD2 at the Coso geothermal field, California; 2006; OFR; 2006-1230; Morrow, C. A.; Lockner, D. A.

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Year Published: 2006

Subsurface structure of the East Bay Plain ground-water basin: San Francisco Bay to the Hayward fault, Alameda County, California

The area of California between the San Francisco Bay, San Pablo Bay, Santa Clara Valley, and the Diablo Ranges (East Bay Hills), commonly referred to as the 'East Bay', contains the East Bay Plain and Niles Cone ground-water basins. The area has a population of 1.46 million (2003 US Census), largely distributed among several cities, including...

Catchings, R.D.; Borchers, J.W.; Goldman, M.R.; Gandhok, G.; Ponce, D.A.; Steedman, C.E.
Subsurface structure of the East Bay Plain ground-water basin: San Francisco Bay to the Hayward fault, Alameda County, California; 2006; OFR; 2006-1084; Catchings, R. D.; Borchers, J. W.; Goldman, M. R.; Gandhok, G.; Ponce, D. A.; Steedman, C. E.

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Year Published: 2006

Seismic constraints and coulomb stress changes of a blind thrust fault system, 2: Northridge, California

We review seismicity, surface faulting, and Coulomb stress changes associated with the 1994 Northridge, California, earthquake. All of the observed surface faulting is shallow, extending meters to tens of meters below the surface. Relocated aftershocks reveal no seismicity shallower than 2 km depth. Although many of the aftershocks lie along the...

Stein, Ross S.; Lin, Jian
Seismic constraints and coulomb stress changes of a blind thrust fault system, 2: Northridge, California; 2006; OFR; 2006-1158; Stein, Ross S.; Lin, Jian

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Year Published: 2006

Seismic constraints and coulomb stress changes of a blind thrust fault system, 1: Coalinga and Kettleman hills, California

This report reviews the seismicity and surface ruptures associated with the 1982-1985 earthquake sequence in the Coalinga region in California, and the role of Coulomb stress in triggering the mainshock sequence and aftershocks. The 1982-1985 New Idria, Coalinga, and Kettleman Hills earthquakes struck on a series of west-dipping, en echelon blind...

Lin, Jian; Stein, Ross S.
Seismic constraints and coulomb stress changes of a blind thrust fault system, 1: Coalinga and Kettleman hills, California; 2006; OFR; 2006-1149; Lin, Jian; Stein, Ross S.

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Year Published: 2006

Digital database of recently active traces of the Hayward fault, California

The purpose of this map is to show the location of and evidence for recent movement on active fault traces within the Hayward Fault Zone, California. The mapped traces represent the integration of the following three different types of data: (1) geomorphic expression, (2) creep (aseismic fault slip),and (3) trench exposures. This publication is...

Lienkaemper, James J.
Digital Database of Recently Active Traces of the Hayward Fault, California; 2006; DS; 177; Lienkaemper, James J.

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Year Published: 2006

Maps of quaternary deposits and liquefaction susceptibility in the Central San Francisco Bay Region, California

This report presents a map and database of Quaternary deposits and liquefaction susceptibility for the urban core of the San Francisco Bay region. It supercedes the equivalent area of U.S. Geological Survey Open-File Report 00-444 (Knudsen and others, 2000), which covers the larger 9-county San Francisco Bay region. The report consists of (1) a...

Witter, Robert C.; Knudsen, Keith L.; Sowers, Janet M.; Wentworth, Carl M.; Koehler, Richard D.; Randolph, Carolyn E.; Brooks, Suzanna K.; Gans, Kathleen D.
Maps of Quaternary Deposits and Liquefaction Susceptibility in the Central San Francisco Bay Region, California; 2006; OFR; 2006-1037; Witter, Robert C.; Knudsen, Keith L.; Sowers, Janet M.; Wentworth, Carl M.; Koehler, Richard D.; Randolph, Carolyn E.; Brooks, Suzanna K.; Gans, Kathleen D.

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Year Published: 2006

USGS science in Menlo Park -- a science strategy for the U.S. Geological Survey Menlo Park Science Center, 2005-2015

In the spring of 2004, the U.S. Geological Survey (USGS) Menlo Park Center Council commissioned an interdisciplinary working group to develop a forward-looking science strategy for the USGS Menlo Park Science Center in California (hereafter also referred to as "the Center"). The Center has been the flagship research center for the USGS in the...

Brocher, Thomas M.; Carr, Michael D.; Halsing, David L.; John, David A.; Langenheim, Victoria E.; Mangan, Margaret T.; Marvin-DiPasquale, Mark C.; Takekawa, John Y.; Tiedeman, Claire

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Year Published: 2006

Trophic structure and avian communities across a salinity gradient in evaporation ponds of the San Francisco Bay estuary

Commercial salt evaporation ponds comprise a large proportion of baylands adjacent to the San Francisco Bay, a highly urbanized estuary. In the past two centuries, more than 79% of the historic tidal wetlands in this estuary have been lost. Resource management agencies have acquired more than 10 000 ha of commercial salt ponds with plans to...

Takekawa, John Y.; Miles, A.K.; Schoellhamer, D.H.; Athearn, N.D.; Saiki, M.K.; Duffy, W.D.; Kleinschmidt, S.; Shellenbarger, G.G.; Jannusch, C.A.
Trophic structure and avian communities across a salinity gradient in evaporation ponds of the San Francisco Bay estuary; 2006; Conference Paper; Hydrobiologia; Takekawa, J. Y.; Miles, A. K.; Schoellhamer, D. H.; Athearn, N. D.; Saiki, M. K.; Duffy, W. D.; Kleinschmidt, S.; Shellenbarger, G. G.; Jannusch, C. A.

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Year Published: 2006

Trophic structure and avian communities across a salinity gradient in evaporation ponds of the San Francisco Bay estuary

Commercial salt evaporation ponds comprise a large proportion of baylands adjacent to the San Francisco Bay, a highly urbanized estuary. In the past two centuries, more than 79% of the historic tidal wetlands in this estuary have been lost. Resource management agencies have acquired more than 10 000 ha of commercial salt ponds with plans...

Takekawa, John Y.; Miles, A.K.; Schoellhamer, D.H.; Athearn, N.D.; Saiki, M.K.; Duffy, W.D.; Kleinschmidt, S.; Shellenbarger, G.G.; Jannusch, C.A.

Filter Total Items: 1,120
Boulder in debris flow
January 14, 2018

Geologists assess scene after debris flow

Geologists assess boulders displaced during the Montecito debris flow event on Jan. 9, 2018.  

Pool warning sign
January 14, 2018

Pool sign warns first responders

Swimming pool sign spray-painted to warn first responders and others to be careful around the potentially dangerous area. 

Montecito after debris flow
January 14, 2018

Montecito after debris flow

The Dec. 4, 2017 Thomas fire, Southern California's largest wildfire on record, burned more than 280,000 acres across Ventura and Santa Barbara counties for nearly a month.

January 4, 2018

Image of the Week - Southern California Wildfires Update

After a month, the wildfires of Southern California are nearly contained. Landsat 8 imagery shows the dramatic burn scars left behind.

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

USGS EROS Center (

...
Air photo of Paul's slide (left); photo of repair equipment/construction (right)
December 31, 2017

Air photo, Paul's slide (left); repair equipment/construction (right)

Paul’s Slide. Left: Air photo taken May 27, 2017, one of many that Beth Haddon will analyze with structure-from-motion software to measure changes in ground elevation. Right: Caltrans employees and contractors use an excavator and bulldozer to remove Paul’s Slide debris from California State Highway 1. Note recent construction of concrete and a line of grouted reinforcing

...
USGS
December 31, 2017

California myotis (Myotis californicus) Call

Bats produce a variety of vocalizations that are used for navigation, feeding, and social communication. Most vocalizations are pitched well above the range of human hearing and are referred to as ultrasonic. These calls are often known as echolocation calls since bats use the echoes produced when a sound bounces off a bug or a building to determine what is in the area. 

...
Cheryl Hapke is now sharing her knowledge of the Big Sur region with Warrick’s team
December 31, 2017

Cheryl Hapke shares her knowledge of the Big Sur region

Cheryl Hapke is now sharing her knowledge of the Big Sur region with Warrick’s team, and she is eager to leap back into studies of Big Sur coastal change.

USGS
December 31, 2017

Hoary Bat (Lasiurus cinereus) Echo Call

Bats produce a variety of vocalizations that are used for navigation, feeding, and social communication. Most vocalizations are pitched well above the range of human hearing and are referred to as ultrasonic. These calls are often known as echolocation calls since bats use the echoes produced when a sound bounces off a bug or a building to determine what is in the area. 

...
USGS scientist collecting samples of aquatic species from the Pike River, Wis., for later analysis of mercury contamination.
December 31, 2017

Collecting samples of aquatic species from the Pike River, Wisconsin

Microbial Biogeochemistry Laboratory — Menlo Park, California. USGS scientist collecting samples of aquatic species from the Pike River, Wis., for later analysis of mercury contamination.

USGS
December 31, 2017

Hoary Bat (Lasiurus cinereus) Social Call

Bats produce a variety of vocalizations that are used for navigation, feeding, and social communication. Most vocalizations are pitched well above the range of human hearing and are referred to as ultrasonic. These calls are often known as echolocation calls since bats use the echoes produced when a sound bounces off a bug or a building to determine what is in the area. 

...
 model grid with four rows and four columns showing A, types of cascading hydrologic response units (HRUs) and B, land-surface a
December 31, 2017

Model Grids with Cascading Hydrologic Response Units

Hypothetical model grid showing A, types of cascading hydrologic response units and B, land-surface altitudes and cascading flow directions.

USGS
December 31, 2017

Yuma myotis (Myotis yumanensis) Call

Bats produce a variety of vocalizations that are used for navigation, feeding, and social communication. Most vocalizations are pitched well above the range of human hearing and are referred to as ultrasonic. These calls are often known as echolocation calls since bats use the echoes produced when a sound bounces off a bug or a building to determine what is in the area. 

...
Filter Total Items: 897
Drought effects at Trinity Lake
May 28, 2015

Although record low precipitation has been the main driver of one of the worst droughts in California history, abnormally high temperatures have also played an important role in amplifying its adverse effects, according to a recent study by the U.S. Geological Survey and university partners.

USGS science for a changing world logo
May 26, 2015

Recently, U.S. Geological Survey researchers and partners working in California’s Channel Islands National Park discovered mammoth remains in uplifted marine deposits that date to about 80,000 years ago, confirming a long-held but never proven hypothesis that mammoths may have been on the Channel Islands long before the last glacial period 25,000 to 12,000 years ago.

Map of sediment thickness in state waters offshore of San Francisco.
May 21, 2015

Three new sets of maps detail the offshore bathymetry, habitats, geology and submarine environment of the seafloor off the coast of San Francisco, Drakes Bay, and Tomales Point.

Lassen Volcanic National Park, California. Northeast side of Lassen Peak, showing the area devastated by mudflows and a lateral
May 19, 2015

2015 marks the centennial of the May 22, 1915 explosive eruption of Lassen Peak.

Flyer thumbnail
April 22, 2015

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

USGS
April 14, 2015

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

Image: Tsunami Evacuation Sign
April 13, 2015

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

Crowdsourced Earthquake Warnings illustration
April 10, 2015

MENLO PARK, Calif.— Smartphones and other personal electronic devices could, in regions where they are in widespread use, function as early warning systems for large earthquakes according to newly reported research.

Crowdsourced Earthquake Warnings illustration
April 10, 2015

MENLO PARK, California — Los teléfonos móviles y otros dispositivos electrónicos personales podrían ayudar en las regiones donde se encuentran en uso generalizado, y pueden funcionar como sistemas de alerta para terremotos mayor según la nueva investigación científica recien publicada.

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

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

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

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

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

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

Filter Total Items: 216