California Seafloor Mapping Program

Science Center Objects

The California Seafloor Mapping Program (CSMP) is a cooperative program to create a comprehensive coastal/marine geologic and habitat base map series for all of California's State waters. The California Ocean Protection Council (COPC) authorized funds to establish the CSMP in 2007 and assembled a team of experts from state and federal agencies, academia, and private industry to develop the best approach to mapping and classifying coastal and marine geologic habitats, while at the same time updating all nautical charts. Initiated in 2008, 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).

Although the CSMP was originally developed to support the design and monitoring of marine reserves through the Marine Life Protection Act [California Department of Fish and Wildlife (CDFW), 2007], accurate statewide mapping of the seafloor has also contributed significantly to these efforts:

  • Definition of habitats for ecosystem-based management
  • Establishing baselines for long-term monitoring of coastal evolution related to climate change, large storms, and anthropogenic influences
  • Enabling modeling of coastal flooding from sea-level rise and large storms
  • Identifying offshore active faults and submarine landslides, providing the basis for earthquake and tsunami hazard assessments and hazard mitigation
  • Providing a database of sediment distribution and thickness, important input for regional sediment management
  • Enabling more effective regulation of offshore development
  • Improving maritime safety
  • Providing a framework for scientific research
  • Facilitating outreach to heighten public education and awareness of coastal ecosystems, resources, and issues

Data collected during this project reveal the seafloor offshore of the California coast in unprecedented detail (for example, see the movie below) and provide an ecosystem context for the effective management of this precious marine resource.

Virtual fly-through over the seafloor of Central California near San Francisco as if the water was drained from the ocean.

The movie flies out of San Francisco Bay pausing over a field of large sand waves west of the Golden Gate, and then up to the Bolinas area revealing folded and fractured bedrock. The movie then turns south flying down the coast past Pacifica and towards Half Moon Bay again revealing folded and fractured bedrock beneath the Maverick's surf break. The movie finishes by flying over very complex seafloor of folded bedrock, fault scarps, and ripple scour depressions south of Half Moon Bay and offshore San Gregorio State Beach. The seafloor is colored for depth with reds and oranges representing shallower regions and dark blues and purples representing deeper regions.

Peter Dartnell, U.S. Geological Survey, Pacific Coastal and Marine Science Center


Objective — create a comprehensive coastal/marine bathymetric, geologic, and habitat base map series for all state waters (MHHW - 3nm).

State Funding — 2006 Safe Drinking Water, Water Quality and Supply, Flood Control, River and Coastal Protection Bond Act of 2006 (Proposition 84).

Federal Funding — NOAA National Ocean Service, Office of Coast Surveys; U.S. Geological Survey Coastal and Marine Geology Program; and American Recovery and Reinvestment Act. 

Basic Components

Bathymetry and Backscatter Data Collection — ship-based, high-resolution sonar data collection for all parts of the coast unmapped as of 2008, about 80% of California’s mainland waters. Visit progress page.

Data ground-truthing — video, still photography, or physical sampling of the seafloor. Visit progress page.

Subbottom profiling — high-resolution, seismic-reflection profiling to determine thickness and distribution of sediment and other geologic units, locations of active faults and folds, submarine landslides, and other features. Visit progress page.

GIS Data and Map Production — creation of GIS databases and multi-sheet folio map sets (1:24,000 scale), which will include bathymetry, geologic and habitat interpretation maps spanning the entire California land/sea margin. Visit map sheets page.

Data Management and Dissemination — creation of an online data repository for the public dissemination of all digital data and map products covering the California state waters. Visit GIS data and metadata page.


CDFW — California Department of Fish and Wildlife  (

CMSP — Coastal and Marine Spatial Planning

COPC — California Ocean Protection Council (

CSMP — California Seafloor Mapping Program

CSUMB — SFML — California State University at Monterey Bay Seafloor Mapping Lab (

GIS — geograpic information system

MHHW — mean higher high water

MLML — Moss Landing Marine Laboratories (

MLPA — California Marine Life Protection Act

MPA — Marine Protected Area

NAMSS — USGS National Archive of Marine Seismic Surveys  (

NOAA — National Oceanic and Atmospheric Administration  (

PCMSC — Pacific Coastal and Marine Science Center (

USGS — U.S. Geological Survey (