Six new sets of maps reveal the diverse and complex range of seafloor habitats along 130 kilometers (80 miles) of the central California coast from the Monterey Peninsula north to Pigeon Point. The publicly available maps can be used by a large stakeholder community to understand and manage California’s vast and valuable marine resources.
The new U.S. Geological Survey publications combine new and legacy data to reveal offshore bathymetry, habitats, geology and seafloor environments in stunningly high resolution. Environments range from the rugged granitic bedrock along the high-energy coasts of the Monterey Peninsula, to the bedrock reefs that form the world-class surfing point breaks on the Santa Cruz County coast, to the smooth sand and mud in a large delta bar at the mouth of the Salinas River, and to the steep walls and sinuous channels of one of the largest underwater canyon systems in the world.
Sam Johnson, the USGS project lead, notes, “The new high-resolution datasets and maps are stimulating research – scientists are excited. Our stakeholders like to say that you can't manage it, monitor it, or model it if you don't know what the ‘it’ is. Our seafloor mapping provides that important ‘it’ to the entire coastal community.”
Seamless onshore-offshore geologic maps incorporating subsurface data document the location and geometry of the San Gregorio fault, and show how different strands of the fault extend through Carmel Canyon, cross the continental shelf west of Santa Cruz and Davenport, and combine to uplift Año Nuevo State Park and Año Nuevo Island. A separate fault system to the east in Monterey Bay is part of an actively deforming wedge of the Earth’s crust caught between the converging San Andreas and San Gregorio faults. The six new sets of California maps are Offshore of Pigeon Point, Offshore of Scott Creek, Offshore of Santa Cruz, Offshore of Aptos,Offshore of Monterey Canyon and Vicinity, and Offshore of Monterey.
The new publications are the latest products of the California Seafloor and Coastal Mapping Program. Each of them includes 10 map sheets, a pamphlet, and a digital data catalog with web services. The web services are a new addition to these and all previous products in the map series, making it easier for people to find and use the digital data on a wide variety of devices, including smartphones. The maps and data have a large range of applications. They provide:
- A foundation for assessing marine protected areas and habitats, and for understanding how marine species such as bull kelp, rockfish, crabs, and sea otters use the seafloor.
- Baselines for monitoring coastal change and sea-level-rise impacts.
- Critical input data for modeling and mitigation of coastal flooding.
- A framework for understanding coastal erosion and developing regional sediment management plans.
- Contributions to earthquake and tsunami hazard assessments.
- More accurate data for safer navigation.
- Essential information for planning, siting, or removing offshore infrastructure.
“These new seafloor maps – used in partnership with the USGS – will give us an additional tool to protect Californians, as well as fish and wildlife. The new maps will be used to analyze offshore faults and earthquake hazards. They will also help us identify sources of sand to replenish beaches – and will help establish a scientific baseline to track changes in habitat near shore over time. This investment will pay off for Californians in ways that we cannot even imagine now,” said California’s Secretary for Natural Resources and OPC Chair John Laird.
California Seafloor and Coastal Mapping Program is a unique collaborative effort to comprehensively survey and map all of California's state waters. It is supported by the USGS, the California Ocean Protection Council, NOAA, California State University at Monterey Bay, Moss Landing Marine Laboratories, and other government, academic, and industry partners.