The seafloor has distinct features and characteristics that help us better understand Earth’s current and past conditions, potential resources, and natural hazards. However, less than 10% of the seafloor has been mapped globally. The USGS conducts high-resolution mapping to describe the physical features of the ocean floor, as well as the geologic layers and structure beneath it.
What's on the seafloor?
The ocean covers more than 70% of the Earth’ surface, yet only a small part of the seafloor has been mapped with enough detail to understand the basic structure, risks, and living and mineral resources that exist there. Characterizing the ocean floor expands our ability to better understand large scale Earth processes along with improved knowledge about the seafloor, deep sea minerals and associated ecosystems. Through this process we can build a more complete view of Earth history, begin to recognize changes, and provide predictions about how the seafloor, underwater environments, and marine geohazards may change in the future.
Technology and Innovation in Seafloor Mapping
Just like the Earth’s land surface, the seafloor contains significant geological and biological features. Geological features include mountains, canyons, plateaus, ledges, and submarine volcanoes, all of which have variable substrate that can range from rocky outcrops to extensive muddy plains, sand ripples, and giant sediment fans along with chemical seeps. Visit the Ocean 101 page to learn more. View a slideshow featuring thickets of coral reefs, sponges, mussels, and the many wondrous creatures that live and move among them.
The USGS designs mapping research programs to address a wide range of topics, and to expand our understanding of deep sea minerals, offshore energy, marine biological habitats, hazards, and more. The USGS uses acoustic techniques to collect detailed information about the seafloor, such as its shape, sediment composition and distribution, and underlying geologic structure and sediment type. Seafloor video, photographs, sediment cores, and other samples are also collected to validate the acoustics and provide a comprehensive foundation for studies of sediment and contaminant transport, landslide and tsunami hazards, gas hydrates, methane and carbon flux, benthic habitat quality, and sediment availability. Managers, policymakers, and other stakeholders use the map products derived from these studies to make informed decisions regarding the Nation’s safety and economic prosperity.
USGS Role in Seafloor Mapping
From habitats to hazards, here are some examples of USGS seafloor mapping efforts.
Mapping the Continental Shelf
The USGS maps continental shelf areas to understand coastal system evolution, from sediment transport to habitat use. Through marine geologic mapping and characterization of inner continental shelf areas, USGS science expands understanding of coastal vulnerability, sediment sources, transport pathways, habitat type and ecosystem characteristics. These activities advance the research and technology essential to coastal evolution and environmental change science while also supporting state and national partners in managing coastal and marine resources and related decisions.
Mapping Beyond the Continental Shelf
Mapping of seafloor and geologic structure beyond the continental shelf is foundational to enhancing stewardship of natural resources, promoting economic prosperity, and strengthening the nation’s security.
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Delineating the U.S. Extended Continental Shelf
USGS Law of the Sea
SQUID-5 camera system
Cascadia Subduction Zone Marine Geohazards
PCMSC MarFac Field Equipment and Capabilities
Marine Geomorphology, Evolution, and Habitats
California Seafloor Mapping Program
Seafloor Faults off Southern California
U.S. West Coast and Alaska Marine Geohazards
EXPRESS: Expanding Pacific Research and Exploration of Submerged Systems
PCMSC Marine Facility (MarFac)
High-Resolution Multichannel Seismic System
Where can I find bathymetric data?
The USGS has made bathymetric surveys for many coastal areas and for a few selected rivers and lakes in the U.S., including Yellowstone Lake, Crater Lake, and Lake Tahoe. Information and data for some of those studies is on the USGS Maps of America's Submerged Lands website. NOAA (National Oceanic and Atmospheric Administration) is the primary source of bathymetric data for the world's oceans. See...
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...
- Overview
What's on the seafloor?
The ocean covers more than 70% of the Earth’ surface, yet only a small part of the seafloor has been mapped with enough detail to understand the basic structure, risks, and living and mineral resources that exist there. Characterizing the ocean floor expands our ability to better understand large scale Earth processes along with improved knowledge about the seafloor, deep sea minerals and associated ecosystems. Through this process we can build a more complete view of Earth history, begin to recognize changes, and provide predictions about how the seafloor, underwater environments, and marine geohazards may change in the future.
Sources/Usage: Public Domain.Technology and Innovation in Seafloor Mapping
Just like the Earth’s land surface, the seafloor contains significant geological and biological features. Geological features include mountains, canyons, plateaus, ledges, and submarine volcanoes, all of which have variable substrate that can range from rocky outcrops to extensive muddy plains, sand ripples, and giant sediment fans along with chemical seeps. Visit the Ocean 101 page to learn more. View a slideshow featuring thickets of coral reefs, sponges, mussels, and the many wondrous creatures that live and move among them.
The USGS designs mapping research programs to address a wide range of topics, and to expand our understanding of deep sea minerals, offshore energy, marine biological habitats, hazards, and more. The USGS uses acoustic techniques to collect detailed information about the seafloor, such as its shape, sediment composition and distribution, and underlying geologic structure and sediment type. Seafloor video, photographs, sediment cores, and other samples are also collected to validate the acoustics and provide a comprehensive foundation for studies of sediment and contaminant transport, landslide and tsunami hazards, gas hydrates, methane and carbon flux, benthic habitat quality, and sediment availability. Managers, policymakers, and other stakeholders use the map products derived from these studies to make informed decisions regarding the Nation’s safety and economic prosperity.
Sources/Usage: Public Domain.USGS Role in Seafloor Mapping
From habitats to hazards, here are some examples of USGS seafloor mapping efforts.
Sources/Usage: Public Domain.As part of the National Strategy for Ocean Mapping, Exploration, and Characterization (NOMEC) initiative, USGS is helping to guide strategic planning, determining priority areas for ocean mapping and characterization, and collecting data and information to better understand the functions and ecological balance of deep-sea environments. The White House Ocean Science and Technology Subcommittee released the NOMEC Strategy in June 2020 to coordinate mapping, exploration, and characterization activities across federal agencies. Check out USGS mapping efforts along the Atlantic margin and Pacific margin.
Sources/Usage: Public Domain.USGS maps the seafloor to identify and characterize habitats such as mesophotic coral ecosystems, deepwater coral ecosystems, deep-ocean environments, and more.
Sources/Usage: Public Domain.USGS seafloor mapping efforts help identify potential hazards like subduction zones where earthquakes could occur and trigger tsunamis, and areas of resource interest such as mineral deposits and areas for offshore wind energy. Mapping the Continental Shelf
The USGS maps continental shelf areas to understand coastal system evolution, from sediment transport to habitat use. Through marine geologic mapping and characterization of inner continental shelf areas, USGS science expands understanding of coastal vulnerability, sediment sources, transport pathways, habitat type and ecosystem characteristics. These activities advance the research and technology essential to coastal evolution and environmental change science while also supporting state and national partners in managing coastal and marine resources and related decisions.
Sources/Usage: Public Domain.The Delmarva Peninsula is a 220-kilometer-long headland, spit, and barrier island complex that was significantly affected by Hurricane Sandy. To better constrain controls on coastal vulnerability and evolution, the region’s sediment sources, transport pathways and sediment sinks must be identified. This project defines the geologic framework of the Delmarva coastal system through geophysical mapping of the inner continental shelf. Learn more
Sources/Usage: Public Domain.The U.S. Geological Survey, in cooperation with the Massachusetts Office of Coastal Zone Management (CZM) is conducting geologic mapping of the sea floor of the Massachusetts inner continental shelf to characterize the surface and shallow subsurface geologic framework within the Massachusetts coastal zone. The overall goal of this project is to determine the geologic framework of the sea floor within the Massachusetts coastal zone, using high-resolution geophysical techniques, sediment sampling, and sea floor photography. Learn more
Sources/Usage: Public Domain. Visit Media to see details.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. The CSMP has collected bathymetry (underwater topography) and backscatter data (providing insight into the geologic makeup of the seafloor) that are being turned into habitat and geologic base maps for all of California's State Waters (mean high water line out to three nautical miles). Learn more Mapping Beyond the Continental Shelf
Mapping of seafloor and geologic structure beyond the continental shelf is foundational to enhancing stewardship of natural resources, promoting economic prosperity, and strengthening the nation’s security.
Sources/Usage: Public Domain.According to Article 76 of the Convention on the Law of the Sea, the United States may extend its offshore seafloor domain beyond 200 M when certain criteria are met. The U.S. has an inherent interest in knowing the full extent of its ECS so that it can better protect, manage, and/or use the resources contained therein. USGS is committed to maintaining and applying state-of-the art ocean technology to increase understanding of earth history, document potential marine hazards, and identify U.S. ocean resources. Learn more.
Sources/Usage: Public Domain.USGS combines expertise in mapping from the continental land mass to deep offshore areas including the continental slope, rise and abyssal plain. These mapping products inform science related to natural hazards, resource management and legal authorities regarding international boundaries. - Publications
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Explore our science
Filter Total Items: 25Delineating the U.S. Extended Continental Shelf
The United States has an interest in knowing the full extent of its continental shelf beyond 200 nautical miles from shore (called the extended continental shelf, or ECS) so that it can better protect, manage and use the resources of the seabed and subsoil contained therein. The USGS contributes to the ECS effort through membership and leadership on the interagency U.S. ECS Task Force, a group...USGS Law of the Sea
The USGS Law of the Sea project helps to determine the outer limits of the extended continental shelf (ECS) of the United States. The ECS is that portion of the continental shelf beyond 200 nautical miles. It is an important maritime zone that holds many resources and vital habitats for marine life. Its size may exceed one million square kilometers, encompassing areas in the Arctic, Atlantic...SQUID-5 camera system
The SQUID-5 is a Structure-from-Motion Quantitative Underwater Imaging Device with 5 cameras.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 SciencePCMSC MarFac Field Equipment and Capabilities
Learn about the USGS Pacific Coastal and Marine Science Center Marine Facility’s vast array of field equipment, sampling devices, and mapping systems, and our capabilities. Our engineers, designers, mechanics, and technicians have also designed and developed some of the specialized field equipment we use in field operations in the nearshore, in the deep sea, and on land.Marine Geomorphology, Evolution, and Habitats
Seafloor resource managers and modelers need seafloor maps that can be combined in GIS, modeling, and statistical analysis environments and related successfully to biologic and oceanographic data. The Marine Geomorphology, Evolution, and Habitats Project encompasses mapping activities and the development of new mapping systems and methodologies. The emphasis is on the role of geologic processes in...California 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.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 ScienceEXPRESS: Expanding Pacific Research and Exploration of Submerged Systems
EXPRESS is a multi-year, multi-institution cooperative research campaign in deep sea areas of California, Oregon, and Washington, including the continental shelf and slope. EXPRESS data and information are intended to guide wise use of living marine resources and habitats, inform ocean energy and mineral resource decisions, and improve offshore hazard assessments.ByCoastal 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, Organic Geochemistry Laboratory, Deep Sea Exploration, Mapping and CharacterizationPCMSC Marine Facility (MarFac)
Learn about the USGS Pacific Coastal and Marine Science Center Marine Facility, or MarFacHigh-Resolution Multichannel Seismic System
Description of the high-resolution multichannel seismic system at the Marine Facility (MarFac) of the USGS Pacific Coastal and Marine Science Center, for seafloor mapping - Data and More
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Where can I find bathymetric data?
The USGS has made bathymetric surveys for many coastal areas and for a few selected rivers and lakes in the U.S., including Yellowstone Lake, Crater Lake, and Lake Tahoe. Information and data for some of those studies is on the USGS Maps of America's Submerged Lands website. NOAA (National Oceanic and Atmospheric Administration) is the primary source of bathymetric data for the world's oceans. See...
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...