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Natural Hazards

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Costs and consequences of natural hazards can be enormous; each year more people and infrastructure are at risk. We develop and apply hazards science to help protect U.S. safety, security, and economic well being. These scientific observations, analyses, and research are crucial for the Nation to become more resilient to natural hazards.

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Filter Total Items: 229
Date published: July 20, 2018
Status: Active

Boulder (BOU)

The Boulder observatory was established in 1963. The grounds for the observatory are overseen by the National Telecommunications and Information Administration of the Department of Commerce. This observatory is closest to Program headquarters in Golden. Therefore, in addition to serving as a site for routine data collection, Boulder also functions as the...

Date published: July 20, 2018
Status: Active

Observatories

Get information on and locations of geomagnetic observatories operated by the USGS and partners of the USGS geomagnetism program.

Date published: July 20, 2018
Status: Active

Instrumentation

See the instruments we use at our geomagnetic observatories and how they help us to gather data.

Date published: July 20, 2018
Status: Active

Monitoring Operations

Learn more about the USGS Geomagnetism operations.

Date published: July 18, 2018
Status: Active

Overview

USGS Geomagnetism Program research staff evaluate data produced by magnetic observatories, including those operated by the USGS, data processing methods, and magnetic indices derived from observatory data.

Contacts: Jeffrey J Love
Date published: July 18, 2018
Status: Active

Overview

Geomagnetically-induced currents (GICs) flowing along electric power-transmission systems and other electrically-conducting infrastructure are produced by a naturally induced geo-electric field during geomagnetic disturbances.

Date published: July 18, 2018
Status: Active

Science for Everyone

Science briefs about new landslides research written for non-scientists.

Contacts: Lisa A Wald
Date published: July 18, 2018
Status: Active

Overview

Reliable earthquake prediction is a worthwhile goal that, if ever attained, would reduce the loss of life and property.

Contacts: Jeffrey J Love
Date published: July 17, 2018
Status: Active

Declination of the Earth 1590-1990

Models created of the declination of the Earth through time.

Date published: July 17, 2018
Status: Active

Operations

Learn more about the USGS Geomagnetism operations.

Date published: July 16, 2018
Status: Active

Landslide Preparedness

Landslide and debris flow warning signs, what to do before, during, and after. 

Date published: July 16, 2018
Status: Active

Flood Hazards

Information about active and recent events tracked by the USGS National Floods Specialist.

Attribution: Natural Hazards
Filter Total Items: 105
Date published: February 15, 2018

National Assessment of Shoreline Change: A GIS compilation of Updated Vector Shorelines and Associated Shoreline Change Data for the Southeast Atlantic Coast

U.S. Geological Survey (USGS) is conducting a national assessment of coastal change hazards.  One component of this research effort, the National Assessment of Shoreline Change Project documents changes in shoreline position as a proxy for coastal change. 

Date published: February 15, 2018

National Assessment of Shoreline Change: A GIS compilation of Updated Vector Shorelines and Associated Shoreline Change Data for the Gulf of Mexico Coast

U.S. Geological Survey (USGS) is conducting a national assessment of coastal change hazards.  One component of this research effort, the National Assessment of Shoreline Change Project, documents changes in shoreline position as a proxy for coastal change. Shoreline position is an easily understood feature representing the historical location of a beach position through time. 

Date published: February 15, 2018

Topographic, imagery, and raw data associated with unmanned aerial systems (UAS) flights over Black Beach, Falmouth, Massachusetts on 18 March 2016

The U.S. Geological Survey worked in collaboration with members of the Marine Biological Laboratory and Woods Hole Analytics at Black Beach, in Falmouth, Massachusetts to explore scientific research demands on UAS technology for topographic and habitat mapping applications. 

Date published: February 15, 2018

Data and calculations to support the study of the sea-air flux of methane and carbon dioxide on the West Spitsbergen margin in June 2014

This dataset collected on the West Spitsbergen margin during U.S. Geological Survey Coastal and Marine Geology Program Field Activity 2014-013-FA, which was carried out in conjunction with the University of Tromso and the GEOMAR Helmholtz Centre for Ocean Research Kiel on the R/V Helmer Hanssen.

Date published: February 15, 2018

Water column physical and chemical properties of Cenote Bang, a component of the Ox Bel Ha cave network within the subterranean estuary coastal aquifer of the Yucatan Peninsula, from December 2013 to January 2016

This dataset, collected during four field events during U.S. Geological Survey (USGS) Coastal and Marine Geology Program Field Activities 2015-013-FA and 2016-003-FA in conjunction with Texas A&M University reports geochemical properties of the water column from Cenote Bang, a component of the Ox Bel Ha cave network that is located 5 km inland from the coast. 

Date published: February 14, 2018

Key Findings for Scenario-Based Assessment for Nor'easters

Percentage of sandy beaches very likely (probability > 0.9) to experience erosion associated with collision, overwash, and inundation during class 1-3 nor’easter impact.

Date published: February 14, 2018

Key Findings for Scenario-Based Assessment for Hurricanes

Percentage of sandy beaches very likely (probability > 0.9) to experience erosion associated with collision, overwash, and inundation during category 1-5 hurricane landfall.

Date published: February 14, 2018

Multichannel sparker seismic-reflection data of field activity 2016-656-FA; between Icy Point and Dixon Entrance, Gulf of Alaska from 2016-08-07 to 2016-08-26

This data release contains high-resolution multichannel seismic (MCS) reflection data collected in August of 2016 along the southeast Alaska continental margin. Structure perpendicular MCS profiles were collected along the Queen Charlotte-Fairweather fault. The data were collected aboard the R/V Norseman using a Delta sparker sound source and recorded on a 64-channel digital streamer...

Date published: February 12, 2018

Shoreline change rates in salt marsh units in Edwin B. Forsythe National Wildlife Refuge, New Jersey

This dataset displays shoreline change rates at the Edwin B. Forsythe National Wildlife Refuge (EBFNWR), which spans over Great Bay, Little Egg Harbor, and Barnegat Bay in New Jersey, USA

Date published: February 12, 2018

Sea floor sediment samples, seabed imagery, and CTD data collected in Stellwagen Bank National Marine Sanctuary, MA in 2015, U.S. Geological Survey Field Activity 2015-062-FA

This field activity is part of the effort to map geologic substrates of the Stellwagen Bank National Marine Sanctuary region off Boston, Massachusetts. The overall goal is to develop high-resolution (1:25,000) interpretive maps, based on multibeam sonar data and seabed sampling, showing surficial geology and seabed sediment dynamics.

Date published: February 12, 2018

Continuous Bathymetry and Elevation Models of the Massachusetts Coastal Zone and Continental Shelf

Integrated terrain models covering 16,357 square kilometers of the Massachusetts coastal zone and offshore waters were built to provide a continuous elevation and bathymetry terrain model for ocean planning purposes.  A Triangulated Irregular Network was created from public-domain bathymetric and LiDAR data using the ArcGIS terrain-model framework and then interpolated into a 32-bit GeoTiff....

Date published: February 12, 2018

Aerial imagery and photogrammetric products from unmanned aerial systems (UAS) flights over the Lake Ontario shoreline at Braddock Bay, New York, July 10 to 11, 2017

Low-altitude (80-100 meters above ground level) digital images were obtained from a camera mounted on a 3DR Solo quadcopter, a small unmanned aerial system (UAS), in three locations along the Lake Ontario shoreline in New York during July 2017. These data were collected to document and monitor effects of high lake levels, including shoreline erosion, inundation, and property damage.

Filter Total Items: 4,147
Year Published: 2018

Leveraging geodetic data to reduce losses from earthquakes

Seismic hazard assessments that are based on a variety of data and the best available science, coupled with rapid synthesis of real-time information from continuous monitoring networks to guide post-earthquake response, form a solid foundation for effective earthquake loss reduction. With this in mind, the Earthquake Hazards Program (EHP) of the U...

Murray, Jessica R.; Roeloffs, Evelyn A.; Brooks, Benjamin A.; Langbein, John O.; Leith, William S.; Minson, Sarah E.; Svarc, Jerry L.; Thatcher, Wayne R.
Murray, J.R., Roeloffs, E.A., Brooks, B.A., Langbein, J., Leith, W., Minson, S.E., Svarc, J., and Thatcher, W., 2018, Leveraging geodetic data to reduce losses from earthquakes: U.S. Geological Survey Open-File Report 2018–1037, 34 p., https://doi.org/10.3133/ofr20181037.

Year Published: 2018

Numerical models of pore pressure and stress changes along basement faults due to wastewater injection: Applications to the 2014 Milan, Kansas Earthquake

We have developed groundwater flow models to explore the possible relationship between wastewater injection and the 12 November 2014 Mw 4.8 Milan, Kansas earthquake. We calculate pore pressure increases in the uppermost crust using a suite of models in which hydraulic properties of the Arbuckle Formation and the Milan earthquake fault zone,...

Hearn, Elizabeth H.; Koltermann, Christine; Rubinstein, Justin R.
Hearn, E. H., C. Koltermann, and J. Rubinstein (2018), Numerical Models of Pore Pressure and Stress Changes Along Basement Faults Due to Wastewater Injection: Applications to the 2014 Milan, Kansas Earthquake, Geochemistry, Geophys. Geosystems, doi:10.1002/2017GC007194.

Year Published: 2018

Proximity of Precambrian basement affects the likelihood of induced seismicity in the Appalachian, Illinois, and Williston Basins, central and eastern United States

A dramatic seismicity rate increase in the central and eastern United States (CEUS) over the past decade has been largely associated with the increase in enhanced oil and gas recovery operations and change in industry practices. However, certain areas of the CEUS that have experienced large increases in oil and gas operations, such as the Bakken...

Skoumal, Robert; Brudzinski, Michael R.; Currie, Brian S.

Year Published: 2018

The HayWired earthquake scenario—Engineering implications

The HayWired Earthquake Scenario—Engineering Implications is the second volume of U.S. Geological Survey (USGS) Scientific Investigations Report 2017–5013, which describes the HayWired scenario, developed by USGS and its partners. The scenario is a hypothetical yet scientifically realistic earthquake sequence that is being used to better...

Detweiler, Shane T.; Wein, Anne M.
Detweiler, S.T., and Wein, A.M., eds., 2018, The HayWired earthquake scenario—Engineering implications: U.S. Geological Survey Scientific Investigations Report 2017–5013–I–Q, 429 p., https://doi.org/10.3133/sir20175013v2.

Year Published: 2018

The HayWired earthquake scenario—We can outsmart disaster

The HayWired earthquake scenario, led by the U.S. Geological Survey (USGS), anticipates the impacts of a hypothetical magnitude-7.0 earthquake on the Hayward Fault. The fault is along the east side of California’s San Francisco Bay and is among the most active and dangerous in the United States, because it runs through a densely urbanized and...

Hudnut, Kenneth W.; Wein, Anne M.; Cox, Dale A.; Porter, Keith A.; Johnson, Laurie A.; Perry, Suzanne C.; Bruce, Jennifer L.; LaPointe, Drew
Hudnut, K.W., Wein, A.M., Cox, D.A., Porter, K.A., Johnson, L.A., Perry, S.C., Bruce, J.L., and LaPointe, D., 2018, The HayWired earthquake scenario—We can outsmart disaster: U.S. Geological Survey Fact Sheet 2018–3016, 6 p., https://doi.org/10.3133/fs20183016.

Year Published: 2018

Measuring impact crater depth throughout the solar system

One important, almost ubiquitous, tool for understanding the surfaces of solid bodies throughout the solar system is the study of impact craters. While measuring a distribution of crater diameters and locations is an important tool for a wide variety of studies, so too is measuring a crater's “depth.” Depth can inform numerous studies including...

Robbins, Stuart J.; Watters, Wesley A.; Chappelow, John E.; Bray, Veronica J.; Daubar, Ingrid J.; Craddock, Robert A.; Beyer, Ross A.; Landis, Margaret E.; Ostrach, Lillian; Tornabene, Livio L.; Riggs, Jamie D.; Weaver, Brian P.
Robbins, S.J. et al., 2018. Measuring impact crater depth throughout the solar system. Meteoritics and Planetary Science, 53(4), 583-626.

Year Published: 2018

Ancient Martian aeolian processes and palaeomorphology reconstructed from the Stimson formation on the lower slope of Aeolis Mons, Gale crater, Mars

Reconstruction of the palaeoenvironmental context of Martian sedimentary rocks is central to studies of ancient Martian habitability and regional palaeoclimate history. This paper reports the analysis of a distinct aeolian deposit preserved in Gale crater, Mars, and evaluates its palaeomorphology, the processes responsible for its deposition, and...

Banham, Steve G.; Gupta, Sanjeev; Rubin, David M.; Watkins, Jessica A.; Sumner, Dawn Y.; Edgett, Kenneth S.; Grotzinger, John P.; Lewis, Kevin W.; Edgar, Lauren; Stack, Kathryn M.; Barnes, Robert; Bell, Jame F. III; Day, Mackenzie D.; Ewing, Ryan C.; Lapotre, Mathieu G.A.; Stein, Nathan T.; Rivera-Hernandez, Frances; Vasavada, Ashwin R.
Banham, S. G., Gupta, S., Rubin, D. M., Watkins, J. A., Sumner, D. Y., Edgett, K. S., Grotzinger, J. P., Lewis, K. W., Edgar, L. A., Stack-Morgan, K. M., Barnes, R., Bell, J. F., Day, M. D., Ewing, R. C., Lapotre, M. G.A., Stein, N. T., Rivera-Hernandez, F. and Vasavada, A. R. (2018), Ancient Martian aeolian processes and palaeomorphology reconstructed from the Stimson formation on the lower slope of Aeolis Mons, Gale crater, Mars. Sedimentology. https://doi.org/10.1111/sed.12469

Year Published: 2018

Relaxed impact craters on Ganymede: Regional variation and high heat flows

Viscously relaxed craters provide a window into the thermal history of Ganymede, a satellite with copious geologic signs of past high heat flows. Here we present measurements of relaxed craters in four regions for which suitable imaging exists: near Anshar Sulcus, Tiamat Sulcus, northern Marius Regio, and Ganymede's south pole. We describe a...

Singer, Kelsi N.; Bland, Michael T.; Schenk, Paul M.; McKinnon, William B.
Sing, K. N., Bland, M. T., Schenk, P. M., McKinnon, W. B., 2018. Relaxed impact craters on Ganymede: Regional variation and high heat flows. Icarus 306, 214-224.

Year Published: 2018

2018 one‐year seismic hazard forecast for the central and eastern United States from induced and natural earthquakes

This article describes the U.S. Geological Survey (USGS) 2018 one‐year probabilistic seismic hazard forecast for the central and eastern United States from induced and natural earthquakes. For consistency, the updated 2018 forecast is developed using the same probabilistic seismicity‐based methodology as applied in the two previous forecasts....

Petersen, Mark D.; Mueller, Charles; Moschetti, Morgan P.; Hoover, Susan M.; Rukstales, Kenneth S.; McNamara, Daniel E.; Williams, Robert A.; Shumway, Allison; Powers, Peter; Earle, Paul; Llenos, Andrea L.; Michael, Andrew J.; Rubinstein, Justin L.; Norbeck, Jack; Cochran, Elizabeth S.
Mark D. Petersen, Charles S. Mueller, Morgan P. Moschetti, Susan M. Hoover, Kenneth S. Rukstales, Daniel E. McNamara, Robert A. Williams, Allison M. Shumway, Peter M. Powers, Paul S. Earle, Andrea L. Llenos, Andrew J. Michael, Justin L. Rubinstein, Jack H. Norbeck, Elizabeth S. Cochran; 2018 One‐Year Seismic Hazard Forecast for the Central and Eastern United States from Induced and Natural Earthquakes. Seismological Research Letters ; 89 (3): 1049–1061. doi: https://doi.org/10.1785/0220180005

Year Published: 2018

Improving near‐real‐time coseismic landslide models: Lessons learned from the 2016 Kaikōura, New Zealand, earthquake

The U.S. Geological Survey (USGS) is developing near‐real‐time global earthquake‐triggered‐landslide products to augment the USGS Prompt Assessment of Global Earthquakes for Response (PAGER) system. The 14 November 2016 Mw">MwMw 7.8 Kaikōura, New Zealand, earthquake provided a test case for evaluating the performance and near‐real‐...

Allstadt, Kate E.; Jibson, Randall W.; Thompson, Eric M.; Massey, Chris; Wald, David J.; Godt, Jonathan W.; Rengers, Francis K.
Allstadt, K.E., Jibson, R.W., Thompson, E.M., Massey, C.I., Wald, D.J., Godt, J.W., Rengers, F.K., 2018, Improving Near‐Real‐Time Coseismic Landslide Models: Lessons Learned from the 2016 Kaikōura, New Zealand, Earthquake, Bulletin of the Seismological Society of America (2018) 108 (3B): 1649-1664.

Year Published: 2018

Overview of the geologic effects of the November 14, 2016, Mw 7.8 Kaikoura, New Zealand, earthquake

The November 14, 2016, Kaikoura, New Zealand, earthquake (moment magnitude [Mw] 7.8) triggered more than 10,000 landslides over an area of about 12,000 square kilometers in the northeastern part of the South Island of New Zealand. In collaboration with GNS Science (the Institute of Geological and Nuclear Science Limited), we conducted ground and...

Jibson, Randall W.; Allstadt, Kate E.; Rengers, Francis K.; Godt, Jonathan W.
Jibson, R.W., Allstadt, K.E., Rengers, F.K., and Godt, J.W., 2018, Overview of the geologic effects of the November 14, 2016, Mw 7.8 Kaikoura, New Zealand, earthquake: U.S. Geological Survey Scientific Investigations Report 2017–5146, 39 p., https://doi.org/10.3133/sir20175146.

Year Published: 2018

Application of microtremor horizontal-to-vertical spectral ratio (MHVSR) analysis for site characterization: State of the art

Nakamura (Q Rep Railway Tech Res Inst 30:25–33, 1989) popularized the application of the horizontal-to-vertical spectral ratio (HVSR) analysis of microtremor (seismic noise or ambient vibration) recordings to estimate the predominant frequency and amplification factor of earthquake shaking. During the following quarter century, popularity in the...

Molnar, S.; Cassidy, J. F. ; Castellaro, S.; Cornou, C.; Crow, H.; Hunter, J. A.; Matsushima, S.; Sánchez-Sesma, F. J.; Yong, Alan K.
Molnar, S., F. Cassidy, J., Castellaro, S., Cornou, C., Crow, H., Hunter, J., Matsushima, S., J. Sánchez-Sesma, F, and Yong, A., 2018, Application of Microtremor Horizontal-to-Vertical Spectral Ratio (MHVSR) Analysis for Site Characterization; State of the Art: Surveys in Geophysics, https://doi.org/10.1007/s10712-018-9464-4.

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Aerial of lava flow
July 8, 2018

Kīlauea Volcano — Kapoho Crater

View of the partially filled Kapoho Crater (center) and the open lava channel where it makes a 90-degree turn around the crater. The open channel no longer directly enters the ocean. Lava flows freely through the channel only to the southern edge of Kapoho Crater (left side of image). Clearly, lava moves into and through the molten core of the thick ‘a‘ā flow across a

...
Lava channel
July 8, 2018

Kīlauea Volcano — Open-Ended Lava Channel

Close view of the "end" of the open lava channel where lava moves beneath the crusted ‘a‘ā flow.

animated GIF showing subsidence at a crater
July 8, 2018

Kīlauea Volcano — Animated GIF of Crater Subsidence

This animated GIF shows a sequence of radar amplitude images that were acquired by the Agenzia Spaziale Italiana CosmoSkyMed satellite system. The images illustrate changes to the 

...
A man stands smiling on a high coastal bluff near solar panels and a pole supported by guy wires, with a camera mounted on top.
July 8, 2018

Video camera installation, Barter Island

USGS oceanographer Shawn Harrison poses in front of the USGS video camera installation atop the coastal bluff of Barter Island in northern Alaska.

Fissure eruption
July 7, 2018

Kīlauea Volcano — Fissure 8

View of Fissure 8 and channel during the morning overflight on July 7.

July 7, 2018

Kīlauea Volcano — Timelapse Changes at Caldera (6/13 - 7/7)

This series of images from June 13 through July 7, 2018, show dramatic down-dropping of part of Kīlauea Volcano's summit caldera floor. For weeks,

...
Camera looking over a summit
July 7, 2018

Kīlauea Volcano — SO2 Camera

For several years, a special ultraviolet camera has been located near Keanakākoʻi Crater at Kīlauea's summit. The camera was capable of detecting SO2 gas coming from Halema‘uma‘u crater. This morning, the camera was removed because there is very little SO2 to measure these days at the summit. In addition, cracking near Keanakākoʻi Crater was making access difficult.

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Men and women sitting in a room with tables and chairs listening to a woman talk, she's pointing at a screen on the wall.
July 7, 2018

USGS hosts community outreach event on Barter Island

USGS oceanographer Li Erikson speaks at a community outreach event on Barter Island, Alaska, to present results from earlier USGS studies and to discuss ongoing USGS research.

Lava entering the ocean
July 6, 2018

Kīlauea Volcano — Kapoho Bay

Ocean entry in Kapoho as viewed from morning helicopter overflight.

Satellite image over crater
July 6, 2018

Kīlauea Volcano — Satellite View of Kīlauea Summit

The WorldView-3 satellite acquired this view of Kīlauea's summit on July 3. Despite a few clouds, the area of heaviest fractures in the caldera is clear. Views into the expanding Halema‘uma‘u crater reveal a pit floored by rubble. HVO, on the northwest caldera rim, is labeled.

A small instrument with a USGS logo sticker with wires coming out of it is in a hole in the ground.
July 5, 2018

Sensitive instrument used to detect ground shaking

This device, called a Raspberry Shake, is a sensitive instrument used to detect ground shaking. It is being carefully buried in this shallow hole in the tundra, to isolate it from wind.

Filter Total Items: 367
Date published: April 25, 2018

Many Low-Lying Atoll Islands Will Be Uninhabitable by Mid-21st Century

Sea-level rise and wave-driven flooding will negatively impact freshwater resources on many low-lying atoll islands in such a way that many could be uninhabitable in just a few decades.

Date published: April 25, 2018

Saltwater contamination of freshwater resources could make many atoll islands uninhabitable in decades

Sea-level rise and wave-driven flooding could introduce saltwater so frequently into atoll islands’ freshwater resources that many will be uninhabitable by the mid-21st century, according to a new study published in ...

Date published: April 24, 2018

East vs West Coast Earthquakes

Why was an earthquake in Virginia felt at more than twice the distance than a similar-sized earthquake in California? The answer is one that many people may not realize. Earthquakes east of the Rocky Mountains can cause noticeable ground shaking at much farther distances than comparably-sized earthquakes in the West.

Date published: April 18, 2018

USGS Rolls Out Groundbreaking Earthquake Study: The HayWired Earthquake Scenario

USGS collaborates with key academic, state, local, and industry partners to provide a new look at what could happen during a major earthquake in the San Francisco Bay Area.

Date published: April 16, 2018

USGS 2017 Excellence in Leadership Award honors scientists who assess coastal flooding threats

Research geologist Patrick Barnard and research oceanographer Li Erikson have been recognized for leading efforts to better assess coastal vulnerability to flooding.

Date published: April 13, 2018

Documentary about sea-level rise threatening the Republic of the Marshall Islands features USGS findings

USGS research in the Republic of the Marshall Islands forms part of the scientific foundation of an interactive documentary released April 6 by PBS Frontline.

Date published: April 12, 2018

USGS beach and nearshore surveys in the media

USGS oceanographer Dan Hoover explained how USGS coastal surveys are conducted and why they are important in a radio interview with NPR affiliate KCLU. KCLU was one of several outlets that reported on ...

Date published: April 4, 2018

USGS Seeks Earthquake Hazards Research Proposals

Applications due May 22, 2018

Date published: March 29, 2018

International Mapping Standards Updated for Planets throughout Solar System

Clarifying Latitude and Longitude for Planets besides Earth

Date published: March 28, 2018

Tracking the movement of sediment and contaminants from northern California wildfire areas to San Francisco Bay

USGS research geologist Renee Takesue of the Pacific Coastal and Marine Science Center collected 20 sediment samples from Sonoma Creek and Napa River north of San Francisco Bay on March 17.

Date published: March 27, 2018

Earthquake Early Warning! New Study Examines Safety Potentials and Limits

In a newly published study, U.S. Geological Survey scientists and their partners calculate possible alert times that earthquake early warning systems can provide people at different levels of ground motion from light to very strong shaking.

Date published: March 26, 2018

Mapping Beach Changes After Devastating Montecito Debris Flows

MEDIA ADVISORY

During the week of March 26, scientists from the U.S. Geological Survey will begin four days of mapping selected beaches and the adjacent seafloor in Santa Barbara and Ventura counties. Results will be compared to surveys from last fall to highlight changes due to winter waves, and to sediment inputs from area streams.