Geologic activity in the ocean can cause dangerous or catastrophic events that threaten lives and critical infrastructure both at sea and on land. The USGS studies these geological events beneath the sea floor, known as marine geohazards, to provide decision makers with the information needed to mitigate risks to human communities, infrastructure, and the environment.
What are marine geohazards?
Marine geohazards, or ‘dangers in the deep’ include earthquakes, volcanic eruptions, submarine landslides, and tsunamis, as well as dissociation of gas hydrates—which can cause seafloor collapse—and oil spills or toxic seeps that affect deep sea life or change the physical characteristics of ocean environments.
Science to Address Hazards
Earthquakes, Landslides, and Tsunamis
Underwater earthquakes and landslides can generate tsunamis that cause hazards for coastal communities. USGS scientists study the subduction zone and the recent history of marine hazards and evaluate the future potential and probable impacts of such events on a regional basis. Quantifying these various hazards (e.g., earthquakes, landslides, tsunamis, and volcanoes) using geological and geophysical data, interpretations, and models improves understanding of the underlying processes of marine geohazards to assess the threats they pose. The USGS develops reliable deterministic and probabilistic estimates of the hazards that are used by engineers and policymakers to help reduce risk.
One barrier to measuring seismic risk has been the scarcity of high-resolution maps of the ocean floor. To fill these gaps, USGS scientists conduct high-resolution mapping offshore, especially near urban regions such as Southern California and the Pacific Northwest that are particularly at risk from seismic hazards. Creating three-dimensional views of the seafloor has given scientists remarkable ways to examine how a fault works, or how fluids may follow underground paths and potentially trigger submarine landslides. These landslides threaten offshore structures such as seafloor pipelines, cables, and equipment for oil and gas exploration. They can also trigger tsunamis that endanger coastal communities worldwide.
To discover a fault’s structure, scientists go to sea to collect streams of data that they turn into comprehensive underwater maps. This type of imaging, along with knowing the age of the sediment along faults and measuring other factors such as magnetics and density, can help tell the story of when the fault last ruptured or how fast it is moving. USGS incorporates these data, which have historically been challenging to collect, into earthquake models to estimate their actual hazard risk. Using high-resolution mapping and seismic technology to gather detailed seafloor data can directly impact human life and cities by improving earthquake and tsunami forecasts.
Research results are used in evaluations of earthquake risk zoning, public disaster education and preparedness, and engineering and building codes. Additionally, reassessing the threat of earthquake, tsunami, and landslide hazards to ports and nuclear power plants can directly impact facility management, emergency-management planning, and plant re-licensing.
The Atlantic and Gulf of Mexico margins are heavily urbanized, support extensive port and industrial/resource facilities, and host 10 nuclear power plants. The USGS completed quantitative assessments of submarine landslides for the U.S. Atlantic coast from Maine to Florida and throughout the Gulf of Mexico to better comprehend the risk of potential submarine landslides and tsunamis to these areas and associated infrastructure.
Gas Hydrates and Seafloor Collapse
Naturally occurring gas hydrates are ice-like combinations of water and (usually methane) gas that form in sediment below the sea floor and in areas of continuous permafrost when pressure and temperature conditions are appropriate.
In deep water marine settings where warm fluids are pumped from great depths below the seafloor for extraction of conventional oil and gas, heating of sediments near a well could lead to breakdown of gas hydrates and release gas and water. Intact gas hydrates generally strengthen marine sediments, and dissociation of gas hydrates could lead to subsidence or collapse of the seafloor near the well. Features associated with natural failure of the seafloor (landslides) have also been linked to gas hydrates in some cases. USGS scientists support submarine geohazards research through field-based surveys that refine understanding of the hydrates-slope failure association and through geotechnical studies that evaluate the response of sediments to dissociation or dissolution of gas hydrates.
Fast rupture of the 2009 Mw 6.9 Canal de Ballenas earthquake in the Gulf of California dynamically triggers seismicity in California
Long-term ocean observing for international capacity development around tsunami early warning
Marine paleoseismic evidence for seismic and aseismic slip along the Hayward-Rodgers Creek fault system in northern San Pablo Bay
California deepwater investigations and groundtruthing (Cal DIG) I: Fault and shallow geohazard analysis offshore Morro Bay
The California Deepwater Investigations and Groundtruthing (Cal DIG) I project focuses on the potential seafloor hazards and impacts of alternative energy infrastructure in the outer continental shelf region offshore of south-central California. This is one of three reports covering a single study area located between Monterey and Point Conception, California in federal waters outside of the State
Earthquake magnitude distributions on northern Caribbean faults from combinatorial optimization models
On-fault earthquake magnitude distributions are calculated for northern Caribbean faults using estimates of fault slip and regional seismicity parameters. Integer programming, a combinatorial optimization method, is used to determine the optimal spatial arrangement of earthquakes sampled from a truncated Gutenberg-Richter distribution that minimizes the global misfit in slip rates on a complex fau
Elevated levels of radiocarbon in methane dissolved in seawater reveal likely local contamination from nuclear powered vessels
Toward an integrative geological and geophysical view of Cascadia subduction zone earthquakes
Submarine canyons, slope failures and mass transport processes in southern Cascadia
Slope failure and mass transport processes along the Queen Charlotte Fault Zone, western British Columbia
Multibeam echosounder (MBES) images, 3.5 kHz seismic-reflection profiles and piston cores obtained along the southern Queen Charlotte Fault Zone are used to map and date mass-wasting events at this transform margin – a seismically active boundary that separates the Pacific Plate from the North American Plate. Whereas the upper continental slope adjacent to and east (upslope) of the fault zone offs
Tsunami history of an Oregon coastal lake reveals a 4600 yr record of great earthquakes on the Cascadia subduction zone
Slope basins, headless canyons, and submarine palaeoseismology of the Cascadia accretionary complex
Cascadia Subduction Zone Marine Geohazards
California Seafloor Mapping Program
Seafloor Faults off Southern California
Hazards: EXPRESS
U.S. West Coast and Alaska Marine Geohazards
Tsunami Hazards, Modeling, and the Sedimentary Record
Tsunami and Earthquake Research
Large Oil Spills
U.S. Geological Survey Gas Hydrates Project
Caribbean Tsunami and Earthquake Hazards Studies
Tracking Oil Spills: Before, During, and Decades Later
Piston and gravity core data collected during USGS cruise 2019-642-FA offshore of south-central California in support of the Bureau of Ocean Energy Management (BOEM) California Deepwater Investigations and Groundtruthing (Cal DIG I) alternative energy pro
Donated ROV vibracore and sampling data collected during Monterey Bay Aquarium Research Institute cruises in 2019 offshore of south-central California
Composite multibeam bathymetry surface and data sources of the southern Cascadia Margin offshore Oregon and northern California
Multichannel seismic-reflection and navigation data collected using SIG ELC1200 and Applied Acoustics Delta Sparkers and Geometrics GeoEel digital streamers during USGS field activity 2020-014-FA.
High-resolution multi-channel and Chirp seismic-reflection data from USGS cruise 2018-641-FA collected in south-central California in support of the Bureau of Ocean Energy Management Cal DIG I offshore alternative energy project
Reprocessed multichannel seismic-reflection (MCS) data from USGS field activity T-1-96-SC collected in San Diego Bay, California in 1996
High-resolution geophysical and geological data collected in Little Egg Inlet and offshore the southern end of Long Beach Island, NJ, during USGS Field Activities 2018-001-FA and 2018-049-FA
Multichannel minisparker, multichannel boomer, and chirp seismic-reflection data of USGS field activity 2017-612-FA collected in Puget Sound and Lake Washington in February of 2017
Chirp sub-bottom data of USGS field activity K0211PS collected in Puget Sound, Washington in April of 2011
Split-beam Echo Sounder and Navigation Data Collected Using a Simrad EK80 Wide Band Tranceiver and ES38-10 Transducer During the Mid-Atlantic Resource Imaging Experiment (MATRIX), USGS Field Activity 2018-002-FA.
Multichannel Seismic-Reflection and Navigation Data Collected Using Sercel GI Guns and Geometrics GeoEel Digital Streamers During the Mid-Atlantic Resource Imaging Experiment (MATRIX), USGS Field Activity 2018-002-FA
Coastal and Marine Hazards and Resources Program
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Natural Hazards Mission Area Headquarters
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Water Resources Mission Area - Headquarters
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What is marine geology?
Geology is the study of the Earth. This includes how the Earth was formed, how the Earth has changed since it was formed, the materials that make up the Earth, and the processes that act on it. Marine Geology focuses on areas affected by our oceans including the deep ocean floor, the shallower slopes and shelves that surround the continents, and coastal areas like beaches and estuaries. USGS...
Will California eventually fall into the ocean?
No, California is not going to fall into the ocean. California is firmly planted on the top of the earth’s crust in a location where it spans two tectonic plates. The San Andreas Fault System, which crosses California from the Salton Sea in the south to Cape Mendocino in the north, is the boundary between the Pacific Plate (that includes the Pacific Ocean) and North American Plate (that includes...
What is the difference between a tsunami and a tidal wave?
Although both are sea waves, a tsunami and a tidal wave are two different and unrelated phenomena. A tidal wave is a shallow water wave caused by the gravitational interactions between the Sun, Moon, and Earth ("tidal wave" was used in earlier times to describe what we now call a tsunami.) A tsunami is an ocean wave triggered by large earthquakes that occur near or under the ocean, volcanic...
What are tsunamis?
Tsunamis are ocean waves triggered by:Large earthquakes that occur near or under the oceanVolcanic eruptionsSubmarine landslidesOnshore landslides in which large volumes of debris fall into the water Scientists do not use the term "tidal wave" because these waves are not caused by tides. Tsunami waves are unlike typical ocean waves generated by wind and storms, and most tsunamis do not "break"...
What is it about an earthquake that causes a tsunami?
Although earthquake magnitude is one factor that affects tsunami generation, there are other important factors to consider. The earthquake must be a shallow marine event that displaces the seafloor. Thrust earthquakes (as opposed to strike slip) are far more likely to generate tsunamis, but small tsunamis have occurred in a few cases from large (i.e., > M8) strike-slip earthquakes. Note the...
Is there a system to warn populations of an imminent occurrence of a tsunami?
NOAA (National Oceanic and Atmospheric Administration) maintains the U.S. Tsunami Warning Centers, and work in conjunction with USGS seismic networks to help determine when and where to issue tsunami warnings. Also, if an earthquake meets certain criteria for potentially generating a tsunami, the pop-up window and the event page for that earthquake on the USGS Latest Earthquakes Map will include a...
What is "vog"? How is it related to sulfur dioxide (SO2) emissions?
Vog (volcanic smog) is a visible haze comprised of gas and an aerosol of tiny particles and acidic droplets created when sulfur dioxide (SO2) and other gases emitted from a volcano chemically interact with sunlight and atmospheric oxygen, moisture, and dust. Volcanic gas emissions can pose environmental and health risks to nearby communities. Vog is a hazard that's associated with Hawaiian...
What is the "Ring of Fire"?
Most earthquakes and volcanic eruptions do not strike randomly but occur in specific areas, such as along plate boundaries. One such area is the circum-Pacific Ring of Fire, where the Pacific Plate meets many surrounding tectonic plates. The Ring of Fire is the most seismically and volcanically active zone in the world. Learn more: USGS Volcano Hazards Program
- Overview
What are marine geohazards?
Marine geohazards, or ‘dangers in the deep’ include earthquakes, volcanic eruptions, submarine landslides, and tsunamis, as well as dissociation of gas hydrates—which can cause seafloor collapse—and oil spills or toxic seeps that affect deep sea life or change the physical characteristics of ocean environments.
Marine geohazards, or ‘dangers in the deep’ include earthquakes, volcanic eruptions, submarine landslides, and tsunamis, as well as dissociation of gas hydrates—which can cause seafloor collapse—and oil spills or toxic seeps that affect deep sea life or change the physical characteristics of ocean environments. Explore more Marine Geology. Science to Address Hazards
Earthquakes, Landslides, and Tsunamis
Seafloor trace of the Queen Charlotte-Fairweather fault (from top left to bottom right) offsets the edge of the Yakobi Sea Valley off southeast Alaska. This 700-mile-long fault has generated large earthquakes in the past. Future shocks—and tsunamis—could threaten coastal communities in the U.S. and Canada. Underwater earthquakes and landslides can generate tsunamis that cause hazards for coastal communities. USGS scientists study the subduction zone and the recent history of marine hazards and evaluate the future potential and probable impacts of such events on a regional basis. Quantifying these various hazards (e.g., earthquakes, landslides, tsunamis, and volcanoes) using geological and geophysical data, interpretations, and models improves understanding of the underlying processes of marine geohazards to assess the threats they pose. The USGS develops reliable deterministic and probabilistic estimates of the hazards that are used by engineers and policymakers to help reduce risk.
One barrier to measuring seismic risk has been the scarcity of high-resolution maps of the ocean floor. To fill these gaps, USGS scientists conduct high-resolution mapping offshore, especially near urban regions such as Southern California and the Pacific Northwest that are particularly at risk from seismic hazards. Creating three-dimensional views of the seafloor has given scientists remarkable ways to examine how a fault works, or how fluids may follow underground paths and potentially trigger submarine landslides. These landslides threaten offshore structures such as seafloor pipelines, cables, and equipment for oil and gas exploration. They can also trigger tsunamis that endanger coastal communities worldwide.
To discover a fault’s structure, scientists go to sea to collect streams of data that they turn into comprehensive underwater maps. This type of imaging, along with knowing the age of the sediment along faults and measuring other factors such as magnetics and density, can help tell the story of when the fault last ruptured or how fast it is moving. USGS incorporates these data, which have historically been challenging to collect, into earthquake models to estimate their actual hazard risk. Using high-resolution mapping and seismic technology to gather detailed seafloor data can directly impact human life and cities by improving earthquake and tsunami forecasts.
Research results are used in evaluations of earthquake risk zoning, public disaster education and preparedness, and engineering and building codes. Additionally, reassessing the threat of earthquake, tsunami, and landslide hazards to ports and nuclear power plants can directly impact facility management, emergency-management planning, and plant re-licensing.
The Atlantic and Gulf of Mexico margins are heavily urbanized, support extensive port and industrial/resource facilities, and host 10 nuclear power plants. The USGS completed quantitative assessments of submarine landslides for the U.S. Atlantic coast from Maine to Florida and throughout the Gulf of Mexico to better comprehend the risk of potential submarine landslides and tsunamis to these areas and associated infrastructure.
Preliminary interpretation of large submarine landslide complexes, major submarine fans, and contourite drifts along the U.S. east coast. Explore the Atlantic and Gulf of Mexico Submarine Landslides-Tsunami Hazards Project. Puerto Rico and the Virgin Islands are located at an active plate boundary between the North American plate and the northeast corner of the Caribbean plate. Plate movements have caused large magnitude earthquakes and devastating tsunamis. The USGS has an ongoing program to identify and map the faults in this region using various geophysical and geological methods in order to estimate the location and magnitude of potential earthquakes. Explore Caribbean Tsunami and Earthquake Hazards Studies. Schematic showing the general setting of seeps on the US Atlantic margin and related processes, such as gas hydrate degradation, groundwater seepage, leakage through fractured rocks, or emissions from the seafloor overlying salt diapirs. Learn about Atlantic Margin Methane Seeps. Gas Hydrates and Seafloor Collapse
Ice-like gas hydrates under capping rock encrusted with mussels on the seafloor of the northern Gulf of Mexico. Naturally occurring gas hydrates are ice-like combinations of water and (usually methane) gas that form in sediment below the sea floor and in areas of continuous permafrost when pressure and temperature conditions are appropriate.
In deep water marine settings where warm fluids are pumped from great depths below the seafloor for extraction of conventional oil and gas, heating of sediments near a well could lead to breakdown of gas hydrates and release gas and water. Intact gas hydrates generally strengthen marine sediments, and dissociation of gas hydrates could lead to subsidence or collapse of the seafloor near the well. Features associated with natural failure of the seafloor (landslides) have also been linked to gas hydrates in some cases. USGS scientists support submarine geohazards research through field-based surveys that refine understanding of the hydrates-slope failure association and through geotechnical studies that evaluate the response of sediments to dissociation or dissolution of gas hydrates.
- Publications
Fast rupture of the 2009 Mw 6.9 Canal de Ballenas earthquake in the Gulf of California dynamically triggers seismicity in California
In the Gulf of California, Mexico, the relative motion across the North America-Pacific boundary is accommodated by a series of marine transform faults and spreading centers. About 40 M>6 earthquakes have occurred in the region since 1960. On 3 August 2009, an Mw 6.9 earthquake occurred near Canal de Ballenas in the region. The earthquake was a strike-slip event with a shallow hypocenter that is lAuthorsWenyuan Fan, Ryo Okuwaki, Andrew Barbour, Yihe Huang, Guoqing Lin, Elizabeth S. CochranLong-term ocean observing for international capacity development around tsunami early warning
The 2004 magnitude (M) 9.1 Sumatra-Andaman Islands earthquake in the Indian Ocean triggered the deadliest tsunami ever, killing more than 230,000 people. In response, the United Nations Educational, Scientific, and Cultural Organization (UNESCO) established three additional Intergovernmental Coordination Groups (ICGs) for the Tsunami and Other Coastal Hazards Early Warning System: for the CaribbeaAuthorsDanielle F. Sumy, Sara McBride, Christa von Hillebrandt-Andrade, Monica D. Kohler, John Orcutt, Shuichi Kodaira, Kate Moran, Daniel McNamara, Takane Hori, Elizabeth Vanacore, Benoit Pirenne, John A. CollinsMarine paleoseismic evidence for seismic and aseismic slip along the Hayward-Rodgers Creek fault system in northern San Pablo Bay
Distinguishing between seismic and aseismic fault slip in the geologic record is difficult, yet fundamental to estimating the seismic potential of faults and the likelihood of multi-fault ruptures. We integrated chirp sub-bottom imaging with targeted cross-fault coring and core analyses of sedimentary proxy data to characterize vertical deformation and slip behavior within an extensional fault benAuthorsJanet Watt, Mary McGann, Renee K. Takesue, Thomas LorensonCalifornia deepwater investigations and groundtruthing (Cal DIG) I: Fault and shallow geohazard analysis offshore Morro Bay
The California Deepwater Investigations and Groundtruthing (Cal DIG) I project focuses on the potential seafloor hazards and impacts of alternative energy infrastructure in the outer continental shelf region offshore of south-central California. This is one of three reports covering a single study area located between Monterey and Point Conception, California in federal waters outside of the State
AuthorsMaureen A. L. Walton, Charlie K Paull, Guy R. Cochrane, Jason A. Addison, Roberto Gwiazda, Daniel J. Kennedy, Eve M. Lundsten, Antoinette Gabrielle PapeshEarthquake magnitude distributions on northern Caribbean faults from combinatorial optimization models
On-fault earthquake magnitude distributions are calculated for northern Caribbean faults using estimates of fault slip and regional seismicity parameters. Integer programming, a combinatorial optimization method, is used to determine the optimal spatial arrangement of earthquakes sampled from a truncated Gutenberg-Richter distribution that minimizes the global misfit in slip rates on a complex fau
AuthorsEric L. Geist, Uri S. ten BrinkElevated levels of radiocarbon in methane dissolved in seawater reveal likely local contamination from nuclear powered vessels
Measurements of the natural radiocarbon content of methane (14C-CH4) dissolved in seawater and freshwater have been used to investigate sources and dynamics of methane. However, during investigations along the Atlantic, Pacific, and Arctic Ocean Margins of the United States, as well as in the North American Great Lakes, some samples revealed highly elevated 14C-CH4 values, as much as 4–5 times aboAuthorsD.J. Joung, Carolyn D. Ruppel, J. Southon, John D. KesslerToward an integrative geological and geophysical view of Cascadia subduction zone earthquakes
The Cascadia subduction zone (CSZ) is an exceptional geologic environment for recording evidence of land level changes, tsunamis, and ground motion that reveals at least 19 great megathrust earthquakes over the past 10 kyr. Such earthquakes are among the most impactful natural hazards on Earth, transcend national boundaries, and can have global impact. Reducing the societal impacts of future eventAuthorsMaureen A. L. Walton, Lydia M. Staisch, Tina Dura, Jessie Kathleen Pearl, Brian L. Sherrod, Joan S. Gomberg, Simon E. Engelhart, Anne Trehu, Janet Watt, Jonathan P. Perkins, Robert C. Witter, Noel Bartlow, Chris Goldfinger, Harvey Kelsey, Ann Morey, Valerie J. Sahakian, Harold Tobin, Kelin Wang, Ray Wells, Erin WirthByNatural Hazards Mission Area, Coastal and Marine Hazards and Resources Program, National Cooperative Geologic Mapping Program, Geosciences and Environmental Change Science Center, Pacific Coastal and Marine Science Center, Core Preparation and Analysis Laboratory and Sample Repositories, Deep Sea Exploration, Mapping and Characterization, Subduction Zone ScienceSubmarine canyons, slope failures and mass transport processes in southern Cascadia
The marine turbidite record along the southern Cascadia Subduction Zone has been used to interpret paleoseismicity and suggest a shorter recurrence interval for large (>M7) earthquakes along this portion of the margin; however, the sources and pathways of these turbidity flows are poorly constrained. We examine the spatial distribution of sediment storage, downslope transport, and slope failures aAuthorsJenna C. Hill, Janet Watt, Daniel S. Brothers, Jared W. KluesnerSlope failure and mass transport processes along the Queen Charlotte Fault Zone, western British Columbia
Multibeam echosounder (MBES) images, 3.5 kHz seismic-reflection profiles and piston cores obtained along the southern Queen Charlotte Fault Zone are used to map and date mass-wasting events at this transform margin – a seismically active boundary that separates the Pacific Plate from the North American Plate. Whereas the upper continental slope adjacent to and east (upslope) of the fault zone offs
AuthorsH. G. Greene, J. Vaughn Barrie, Daniel S. Brothers, James E. Conrad, Kim Conway, Amy E. East, Randolph J. Enkin, Katherine L. Maier, Maureen A. L. Walton, K .M. M. RohrTsunami history of an Oregon coastal lake reveals a 4600 yr record of great earthquakes on the Cascadia subduction zone
Bradley Lake, on the southern Oregon coastal plain, records local tsunamis and seismic shaking on the Cascadia subduction zone over the last 7000 yr. Thirteen marine incursions delivered landward-thinning sheets of sand to the lake from nearshore, beach, and dune environments to the west. Following each incursion, a slug of marine water near the bottom of the freshwater lake instigated a few-year-AuthorsH.M. Kelsey, A. R. Nelson, E. Hemphill-Haley, Robert C. WitterSlope basins, headless canyons, and submarine palaeoseismology of the Cascadia accretionary complex
A combination of geomorphological, seismic reflection and geotechnical data constrains this study of sediment erosion and deposition at the toe of the Cascadia accretionary prism. We conducted a series of ALVIN dives in a region south of Astoria Canyon to examine the interrelationship of fluid flow and slope failure in a series of headless submarine canyons. Elevated head gradients at the inflectiAuthorsB. G. McAdoo, Daniel L. Orange, Elizabeth Screaton, H. Lee, Robert Kayen - Science
Cascadia Subduction Zone Marine Geohazards
Societal Issue: Uncertainty related to rupture extent, slip distribution, and recurrence of past subduction megathrust earthquakes in the Pacific Northwest (northern CA, OR, WA, and southern BC) leads to ambiguity in earthquake and tsunami hazard assessments and hinders our ability to prepare for future events.ByNatural Hazards Mission Area, Coastal and Marine Hazards and Resources Program, Pacific Coastal and Marine Science Center, 3-D CT Core Imaging Laboratory, Core Preparation and Analysis Laboratory and Sample Repositories, Multi-Sensor Core Logger Laboratory, Deep Sea Exploration, Mapping and Characterization, Subduction Zone ScienceCalifornia Seafloor Mapping Program
The California Seafloor Mapping Program (CSMP) is a cooperative program to create a comprehensive coastal and marine geologic and habitat base map series for all of California's State waters.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.Hazards: EXPRESS
Marine geohazards including earthquakes, landslides, and tsunamis lie offshore of densely populated areas of California, Oregon, and Washington. One goal of EXPRESS is to improve assessments of these hazards.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.ByNatural Hazards Mission Area, Coastal and Marine Hazards and Resources Program, Pacific Coastal and Marine Science Center, 3-D CT Core Imaging Laboratory, Core Preparation and Analysis Laboratory and Sample Repositories, Big Sur Landslides, Deep Sea Exploration, Mapping and Characterization, Subduction Zone ScienceTsunami Hazards, Modeling, and the Sedimentary Record
Basic research to develop the geologic record of paleotsunamis and improve the ability to interpret that record is needed to mitigate tsunami risk in the U.S.ByNatural Hazards Mission Area, Coastal and Marine Hazards and Resources Program, Pacific Coastal and Marine Science Center, 3-D CT Core Imaging Laboratory, Core Preparation and Analysis Laboratory and Sample Repositories, Multi-Sensor Core Logger Laboratory, Sediment Lab Suite and Carbon Analysis Laboratory, Subduction Zone ScienceTsunami and Earthquake Research
Here you will find general information on the science behind tsunami generation, computer animations of tsunamis, and summaries of past field studies.Large Oil Spills
Oil spills, such as the 2010 Deepwater Horizon Oil Spill, are impactful environmental disasters that have long lasting effects to the landscape, native species, and inhabitants who depend on the area. The USGS explores the adverse effect that large-scale oil spills have on the environment and helps responders prepare for environmental recovery and rehabilitation.U.S. Geological Survey Gas Hydrates Project
The USGS Gas Hydrates Project has been making contributions to advance understanding of US and international gas hydrates science for at least three decades. The research group working on gas hydrates at the USGS is among the largest in the US and has expertise in all the major geoscience disciplines, as well as in the physics and chemistry of gas hydrates, the geotechnical properties of hydrate...Caribbean Tsunami and Earthquake Hazards Studies
Puerto Rico and the Virgin Islands are located at an active plate boundary between the North American plate and the northeast corner of the Caribbean plate. Plate movements have caused large magnitude earthquakes and devastating tsunamis. The USGS has an ongoing program to identify and map the faults in this region using various geophysical and geological methods in order to estimate the location...Tracking Oil Spills: Before, During, and Decades Later
On March 24, 1989, the Exxon Valdez ran aground in Prince William Sound, Alaska, spilling nearly 11 million gallons of crude oil. At the time, the spill was the Nation’s largest environmental disaster. - Data and More
Piston and gravity core data collected during USGS cruise 2019-642-FA offshore of south-central California in support of the Bureau of Ocean Energy Management (BOEM) California Deepwater Investigations and Groundtruthing (Cal DIG I) alternative energy pro
This data release includes photographs, multi-sensor core logger (MSCL), porewater analyses, and location and depth data from piston and gravity cores collected off the south-central California coast. This dataset is one of several collected as part of the Bureau of Ocean Energy Management (BOEM)-funded California Deepwater Investigations and Groundtruthing (Cal DIG I) project. The purpose of theDonated ROV vibracore and sampling data collected during Monterey Bay Aquarium Research Institute cruises in 2019 offshore of south-central California
This dataset includes photographs of vibracores that were collected by the Monterey Bay Aquarium Research Institute (MBARI) in February 2019 and November 2019 aboard the R/V Western Flyer using the remotely operated vehicle (ROV) Doc Ricketts. The collection of these cores was funded entirely by MBARI, and the cores have been donated to the U.S. Geological Survey (USGS). The cores were collected iComposite multibeam bathymetry surface and data sources of the southern Cascadia Margin offshore Oregon and northern California
Bathymetry data from various sources, including newly released 2018 and 2019 multibeam data collected by the National Oceanic and Atmospheric Administration (NOAA) and the U.S. Geological Survey (USGS), were combined to create a composite 30-m resolution multibeam bathymetry surface of the southern Cascadia Margin offshore of Oregon and northern California. The bathymetry data are available as a 3Multichannel seismic-reflection and navigation data collected using SIG ELC1200 and Applied Acoustics Delta Sparkers and Geometrics GeoEel digital streamers during USGS field activity 2020-014-FA.
In March 2020, the U.S. Geological Survey and the University of Puerto Rico Mayaguez (UPRM) Department of Marine Sciences conducted a marine seismic-reflection experiment focused on observing geophysical evidence of submarine faulting and mass wasting related to the southwestern Puerto Rico seismic sequence of 2019-20. The seismic sequence culminated with a magnitude 6.4 earthquake centered beneatHigh-resolution multi-channel and Chirp seismic-reflection data from USGS cruise 2018-641-FA collected in south-central California in support of the Bureau of Ocean Energy Management Cal DIG I offshore alternative energy project
This dataset is one of several collected as part of the Bureau of Ocean Energy Management (BOEM)-funded California Deepwater Investigations and Groundtruthing (Cal DIG I) project. The purpose of the study is to assess shallow geohazards, benthic habitats, and thereby the potential for alternative energy infrastructure (namely floating wind turbines) offshore south-central California due to its proReprocessed multichannel seismic-reflection (MCS) data from USGS field activity T-1-96-SC collected in San Diego Bay, California in 1996
This data release presents reprocessed multichannel seismic-reflection (MCS) data that was originally collected in 1996 in partnership with the California Division of Mines and Geology and Caltrans as part of a seismic hazard assessment of the Coronado Bridge in San Diego Bay, California. The original survey collected 130 km of data with a 14-cubic inch sleeve-gun (airgun) source, a 24-channel strHigh-resolution geophysical and geological data collected in Little Egg Inlet and offshore the southern end of Long Beach Island, NJ, during USGS Field Activities 2018-001-FA and 2018-049-FA
The natural resiliency of the New Jersey barrier island system, and the efficacy of management efforts to reduce vulnerability, depends on the ability of the system to recover and maintain equilibrium in response to storms and persistent coastal change. This resiliency is largely dependent on the availability of sand in the beach system. In an effort to better understand the system's sand budget aMultichannel minisparker, multichannel boomer, and chirp seismic-reflection data of USGS field activity 2017-612-FA collected in Puget Sound and Lake Washington in February of 2017
High-resolution multichannel minisparker, multichannel boomer and chirp seismic-reflection data were collected by the U.S. Geological Survey and the University of Washington in February of 2017 west of Seattle in Puget Sound and in Lake Washington, Washington. Data were collected aboard University of Washington's R/V Clifford A. Barnes during USGS field activity 2017-612-FA. Sub-bottom acoustic peChirp sub-bottom data of USGS field activity K0211PS collected in Puget Sound, Washington in April of 2011
High-resolution chirp sub-bottom data were collected by the U.S. Geological Survey in April 2011 south of Bainbridge Island and west of Seattle in Puget Sound, Washington. Data were collected aboard the R/V Karluk during field activity K0211PS using an Edgetech SB-512i sub-bottom profiler. Sub-bottom acoustic penetration spans several tens of meters and is variable by location.Split-beam Echo Sounder and Navigation Data Collected Using a Simrad EK80 Wide Band Tranceiver and ES38-10 Transducer During the Mid-Atlantic Resource Imaging Experiment (MATRIX), USGS Field Activity 2018-002-FA.
In summer 2018, the U.S. Geological Survey partnered with the U.S Department of Energy and the Bureau of Ocean Energy Management to conduct the Mid-Atlantic Resources Imaging Experiment (MATRIX) as part of the U.S. Geological Survey Gas Hydrates Project. The field program objectives were to acquire high-resolution 2-dimensional multichannel seismic-reflection and split-beam echosounder data alongMultichannel Seismic-Reflection and Navigation Data Collected Using Sercel GI Guns and Geometrics GeoEel Digital Streamers During the Mid-Atlantic Resource Imaging Experiment (MATRIX), USGS Field Activity 2018-002-FA
In summer 2018, the U.S. Geological Survey partnered with the U.S Department of Energy and the Bureau of Ocean Energy Management to conduct the Mid-Atlantic Resources Imaging Experiment (MATRIX) as part of the U.S. Geological Survey Gas Hydrates Project. The field program objectives were to acquire high-resolution 2-dimensional multichannel seismic-reflection and split-beam echosounder data along - Multimedia
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Coastal and Marine Hazards and Resources Program
12201 Sunrise Valley Dr
Reston, VA 20192
United StatesPacific Coastal and Marine Science Center
2885 Mission Street
Santa Cruz, CA 95060
United StatesSt. Petersburg Coastal and Marine Science Center
600 4th Street South
St. Petersburg, FL 33701
United StatesWoods Hole Coastal and Marine Science Center
384 Woods Hole Rd.
Woods Hole, MA 02543
United StatesNatural Hazards Mission Area Headquarters
12201 Sunrise Valley Dr
Reston, VA 20192
United StatesWater Resources Mission Area - Headquarters
USGS Headquarters
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Reston, VA 20192
United States - FAQ
What is marine geology?
Geology is the study of the Earth. This includes how the Earth was formed, how the Earth has changed since it was formed, the materials that make up the Earth, and the processes that act on it. Marine Geology focuses on areas affected by our oceans including the deep ocean floor, the shallower slopes and shelves that surround the continents, and coastal areas like beaches and estuaries. USGS...
Will California eventually fall into the ocean?
No, California is not going to fall into the ocean. California is firmly planted on the top of the earth’s crust in a location where it spans two tectonic plates. The San Andreas Fault System, which crosses California from the Salton Sea in the south to Cape Mendocino in the north, is the boundary between the Pacific Plate (that includes the Pacific Ocean) and North American Plate (that includes...
What is the difference between a tsunami and a tidal wave?
Although both are sea waves, a tsunami and a tidal wave are two different and unrelated phenomena. A tidal wave is a shallow water wave caused by the gravitational interactions between the Sun, Moon, and Earth ("tidal wave" was used in earlier times to describe what we now call a tsunami.) A tsunami is an ocean wave triggered by large earthquakes that occur near or under the ocean, volcanic...
What are tsunamis?
Tsunamis are ocean waves triggered by:Large earthquakes that occur near or under the oceanVolcanic eruptionsSubmarine landslidesOnshore landslides in which large volumes of debris fall into the water Scientists do not use the term "tidal wave" because these waves are not caused by tides. Tsunami waves are unlike typical ocean waves generated by wind and storms, and most tsunamis do not "break"...
What is it about an earthquake that causes a tsunami?
Although earthquake magnitude is one factor that affects tsunami generation, there are other important factors to consider. The earthquake must be a shallow marine event that displaces the seafloor. Thrust earthquakes (as opposed to strike slip) are far more likely to generate tsunamis, but small tsunamis have occurred in a few cases from large (i.e., > M8) strike-slip earthquakes. Note the...
Is there a system to warn populations of an imminent occurrence of a tsunami?
NOAA (National Oceanic and Atmospheric Administration) maintains the U.S. Tsunami Warning Centers, and work in conjunction with USGS seismic networks to help determine when and where to issue tsunami warnings. Also, if an earthquake meets certain criteria for potentially generating a tsunami, the pop-up window and the event page for that earthquake on the USGS Latest Earthquakes Map will include a...
What is "vog"? How is it related to sulfur dioxide (SO2) emissions?
Vog (volcanic smog) is a visible haze comprised of gas and an aerosol of tiny particles and acidic droplets created when sulfur dioxide (SO2) and other gases emitted from a volcano chemically interact with sunlight and atmospheric oxygen, moisture, and dust. Volcanic gas emissions can pose environmental and health risks to nearby communities. Vog is a hazard that's associated with Hawaiian...
What is the "Ring of Fire"?
Most earthquakes and volcanic eruptions do not strike randomly but occur in specific areas, such as along plate boundaries. One such area is the circum-Pacific Ring of Fire, where the Pacific Plate meets many surrounding tectonic plates. The Ring of Fire is the most seismically and volcanically active zone in the world. Learn more: USGS Volcano Hazards Program