Unified Interior Regions


States L2 Landing Page Tabs

Filter Total Items: 365
Date Published: August 8, 2013
Status: Completed


The SAFRR project’s second scenario, called ARkStorm, addresses massive U.S. West Coast storms analogous to those that devastated California in 1861–62. Storms of this magnitude are projected to become more frequent and intense as a result of climate change. The SAFRR project assembled experts from scientific research agencies to design the large, but scientifically plausible, hypothetical...

red water flowing in a very rocky streambed
Date Published: May 24, 2013
Status: Active

Iron Mountain: An Extraordinary and Extreme Environment

At its peak production, Iron Mountain ranked as the tenth largest copper production site in the world, sixth in the U.S. and first in California. During its operation, from 1879 - 1963, ten different mines throughout the site's 4,400 acres were the source of not just copper, but also silver, iron, gold, zinc and pyrite (iron sulfide).

A century of active mining at Iron Mountain took an...

A screen shot of Delta Skelta serious game
Date Published: April 19, 2013
Status: Completed

Serious Games for Science

Serious or pedagogical games are an engaging way to educate decisionmakers and stakeholders about environmental challenges that are usefully informed by natural and social scientific information and knowledge. USGS designed two serious games intended to promote interactive learning and exploration in the face of large uncertainties, divergent values, and complex situations. Delta Skelta...

UAS discharge measurement Tanana River Train Bridge AK
Date Published: March 1, 2013
Status: Active

SWOT - Surface Water and Ocean Topography

Satellite altimetry associated with the Surface Water and Ocean Topography (SWOT) mission offers a solution for measuring (1) river stage and slope, (2) water surface area including mean channel width and (3) derivatives such as river discharge. The measurements can be used to track changes in these variables and provide an accounting of the Earth's fresh-water bodies from space at the reach...

Contacts: John W Fulton
map of the central valley with the CVHM grid cells overlaid, and a cross section of the subsurface
Date Published: August 27, 2012
Status: Active

Central Valley Hydrologic Model (CVHM)

In an effort to aid water managers in understanding how water moves through the aquifer system, predicting water-supply scenarios, and addressing issues related to water competition, the USGS developed a new hydrologic modeling tool, the Central Valley Hydrologic Model (CVHM). The CVHM is an extensive, detailed three-dimensional (3D) computer model of the hydrologic system of the Central...

Contacts: Claudia C Faunt
close-up Santa Ana Sucker
Date Published: September 28, 2011
Status: Completed

Native Fish Population and Habitat Study - Santa Ana River

California Water Science Center scientists further research on two native fish species.

Contacts: Larry Brown
Longfin Smelt
Date Published: September 28, 2011
Status: Completed

Exploring Drivers of Pelagic Fish Population Decline in Bay-Delta

USGS scientists develop spatially explicit ecosystem model to explore changes pelagic fish species population and distribution in the Sacramento-San Joaquin Delta and Suisun Bay.

Contacts: Larry Brown
Date Published: May 6, 2009
Status: Completed

Sources of Microbial Contamination at Public Beaches, Santa Barbara

The focus of this study is on analysis of existing hydrologic, chemical, and microbiological data; collection of surface-water and shallow ground-water hydrologic, chemical, and microbiological data; and characterization of dissolved organic carbon composition.

Contacts: John Izbicki
ShakeOut Don't Freak Out
Date Published: May 14, 2008
Status: Completed


The ShakeOut Scenario was located in southern California where earthquake risk is high compared to the rest of the country. This scenario is a hypothetical, but plausible 7.8 magnitude earthquake on the southern San Andreas Fault. This scenario was completed in May 2008. The ShakeOut Scenario is described in two publications: The Scenario (Jones and others) and The Narrative (Perry and others...

Thumbnail of a poster which is laid out with photos, images, and text.
Date Published: January 1, 2008
Status: Completed

Does Pleasure Point Need A Seawall?

Information about the USGS Pacific Coastal and Marine Science Center's study of Pleasure Point in Santa Cruz, California, from 2005-2007.

Contacts: Curt Storlazzi
Thumbnail of a poster which is laid out with photos, images, and text.
Date Published: January 1, 2005
Status: Completed

Should Englebright Dam Be Removed?

Information about the USGS Pacific Coastal and Marine Science Center's study from 2001-2004, on Englebright Dam and the science behind its removal.

Thumbnail of a poster which is laid out with photos, images, and text.
Date Published: January 1, 2004
Status: Completed

Tsunami Hazards in the Santa Barbara Channel

Information about the USGS Pacific Coastal and Marine Science Center's study of tsunami hazards in the Santa Barbara Channel from 1993-2003.

Filter Total Items: 350
Screen shot of NSDI node for HA694C
January 1, 2009

This data set consists of hydrographic area and major flow system boundaries and polygons delineated at 1:1,000,000-scale for the Great Basin.

Screen shot of NSDI node for SIR 2004-5155
November 8, 2004

This dataset consists of digital geologic data for the Dry Valley Hydrographic area, Nevada and California. It was compiled from individual 1:250,000-scale geologic data for Washoe County, Nevada, 1:62,500-scale geologic data for the Chilcoot and Doyle 15' quadrangles in California and the results of field mapping within the study area in 2004. 

Filter Total Items: 1,158
January 26, 2017

PubTalk 1/2017 — Unusual sources of tsunamis

A presentation on "Unusual Sources of Tsunamis From Krakatoa to Monterey Bay" by Eric Geist, USGS Research Geophysicist

- Not all tsunamis are generated by earthquakes.
- Tsunamis can be caused by volcanoes, landslides, and even atmospheric disturbances
- Data from tide gauges can help unravel the complex physics of these sources


January 20, 2017

Post-wildfire debris flow: 2016 Fish Fire, Las Lomas Canyon

The June 2016 Fish Fire burned over 12 km^2 in Los Angeles County, California. After the fire, the USGS installed an automated rain-triggered camera to monitor post-wildfire flooding and debris flow in a small canyon above the Las Lomas debris basin in Duarte. This video shows the peak flow triggered by an intense rainstorm on January 20, 2017.

Invasive Aquatic Vegetation
January 16, 2017

Invasive water primrose

Invasive water primrose (Ludwigia species) and water hyacinth (Eichhornia crassipes) line the marsh edge in Mandeville Cut near the Port of Stockton, California’s third largest port.  Invasive aquatic vegetation – dominated by Brazilian waterweed, water hyacinth, and water primrose – has increased exponentially in recent years, clogging about 17,400

delta waters with a significant amount of floating vegetation
January 16, 2017

Invasive Aquatic Vegetation, Sacramento-San Joaquin Delta

Invasive aquatic vegetation chokes Lindsey Slough, creating a potentially challenging environment for fish and other aquatic life. The slough is the site of a 2014 restoration project in the Sacramento-San Joaquin Delta to improve freshwater tidal marsh and spawning habitat for Delta smelt and other fish.

a woman pulls vegetation out of the water with a rake
January 16, 2017

Invasive Brazilian Waterweed, Sacramento-San Joaquin Delta

Landscape ecologist Shruti Khanna uses a threshing rake to collect Brazilian waterweed (Egeria densa) in the Delta. The USGS is conducting research to measure the impact of invasive aquatic vegetation on sediment transport, turbidity, and marsh accretion rates in Delta. 

Photographic panorama showing the San Lorenzo river flowing wide and muddy into the ocean, past the Santa Cruz Beach Boardwalk.
January 8, 2017

Atmospheric River Fills California Rivers with Water and Sediment

An atmospheric river, or narrow band of moisture moving from the tropics to the higher latitudes, hit California in early January and brought the first heavy rains of 2017. While these storms help a drought-stricken state, the onslaught of rain triggers floods and mudslides, and fills rising rivers with sediment and debris. Here the San Lorenzo River flows full and muddy

Large waves crashing on rocks at beach.
December 31, 2016

Storm waves in Santa Cruz

Large storm waves crashing on the rocks near Santa Cruz, California

Map of the seafloor showing its characteristics which include long, linear features that are earthquake fault zones.
December 31, 2016

Offshore of Point Estero

Seafloor offshore of Point Estero (PE) showing east (EH) and west (WH) strands of the Hosgri fault zone. Arrow points to a seafloor slope (a 12,000 year old shoreline) that has been offset by the east Hosgri strand, indicating a slip rate of about 2.6 millimeters per year.

Yosemite Toad
December 31, 2016

Yosemite Toad Vocalization

Amphibians’ permeable skin makes them incredibly sensitive to changes in their environment. Scientists and conservationists alike are using them as “sentinel species” that could provide early warnings of ecosystem change and stress affecting them and other organisms. Next time you are out, stop and listen. Do you hear them?

Image shows a sample of elbaite on a black background
December 31, 2016


Elbaite is one of the best-known members of the tourmaline mineral family, particularly for its high-quality gemstones. Read more about the tourmaline mineral family here

Sample provided by Carlin Green, USGS. Sample originated from Himalaya Mine, California, and is 4

man pointing to image on computer screen in an office setting
December 31, 2016

Geologist explains photo analysis of Calif. coastal cliffs

USGS research geologist Jon Warrick explains how his team applied structure-from-motion analysis to photos from the California Coastal Records Project to measure coastal change. Jon Warrick explains a “difference map” constructed from structure-in-motion data. Red areas indicate loss of material (erosion); blue areas show addition of material (deposition).

Map of the San Joaquin Valley displaying contours of land subsidence that occurred from 2008 to 2010.
December 31, 2016

2008-2010 Land Subsidence Contours, San Joaquin Valley, California

Land subsidence contours showing vertical changes in land surface in the central San Joaquin Valley area, California, during January 8, 2008-January 13, 2010. The top graph illustrates elevation changes computed from repeat geodetic surveys along Highway 152 for 1972-2004. The bottom graph depicts elevation changes computed from repeat geodetic surveys along the Delta-

Filter Total Items: 912
June 26, 2012

Tools, Resources for Earthquake Readiness and Emergency Management To Be Shared, Explained by U.S. Geological Survey Scientists at Conference at Caltech

June 26, 2012

MENLO PARK, Calif. —Throughout the United States, June is recognized as National Oceans Month.  This Thursday, the U.S. Geological Survey invites the public to a lecture entitled "Scanning the Seafloor with Sound." 

June 5, 2012

California, Louisiana and Mississippi join the more than 40 states covered by the US Topo

May 30, 2012

MENLO PARK, Calif. —May is American Wetlands Month. Hear how U.S. Geological Survey scientists are supporting the ongoing restoration efforts to improve South Bay wetlands for endangered species and migratory birds, as well as conducting studies to better understand this wetland ecosystem, and how adaptive management practices will be working over the coming decades to restore...

May 29, 2012

MENLO PARK, Calif. – 100 years ago, in June 1912, the largest volcanic eruption of the 20th century took place in what is now Alaska's Katmai National Park and Preserve. U.S. Geological Survey geologist Judy Fierstein, co-author of a new landmark study on this huge volcanic event, shares her work with the community in a free public lecture Wednesday, June 6, a century to the...

May 28, 2012

SANTA CRUZ, Calif. — The results of an innovative collaboration that paired artists from California’s central coast and the greater San Francisco Bay Area with scientists from the U.S. Geological Survey’s Pacific Coastal and Marine Science Center, will be on display at the R. Blitzer Gallery in Santa Cruz June 1 through July 7. 

May 23, 2012

CARNELIAN BAY, Calif. — Results of a new U.S. Geological Survey study conclude that faults west of Lake Tahoe, Calif., referred to as the Tahoe-Sierra frontal fault zone, pose a substantial increase in the seismic hazard assessment for the Lake Tahoe region of California and Nevada, and could potentially generate earthquakes with magnitudes ranging from 6.3 to 6.9. 

May 22, 2012

SANTA CRUZ, Calif. — The results of an innovative collaboration that paired artists from California's central coast and the greater San Francisco Bay Area with scientists from the U.S. Geological Survey's Pacific Coastal and Marine Science Center, will be on display at the R. Blitzer Gallery in Santa Cruz during June. 

Lassen Peak viewed from the south at the summit of Brokeoff Volcano...
May 22, 2012

On May 22, 1915 an explosive volcanic eruption occurred at Lassen Peak, California.

May 18, 2012

MENLO PARK, Calif. – Members of the news media are invited to attend the U.S. Geological Survey Open House in Menlo Park this weekend.  This event includes over 80 exhibits that highlight the work USGS scientists do. Join them in action as they share the excitement of their scientific work and discoveries with the general public. 

May 16, 2012

PORTLAND, Ore.­– The U.S. Geological Survey has developed models to help water managers identify strategies to use groundwater for meeting competing water demands in the semi-arid upper Klamath Basin. 

May 9, 2012

MENLO PARK, Calif. – Many Bay Area residents know what it’s like to experience an earthquake, but fewer of them know why earthquakes happen. The concepts behind earthquakes and living safely in earthquake country are as simple as a fishing line hooked to a stack of bricks, explains USGS geophysicist Ross Stein, whose family-friendly seismic demos and models are part of the...