USGS releasing maps of state’s coastal seafloor

Science and technology have peeled back a veil of water just off the California coast to reveal detailed information about the seafloor previously unknown to researchers. Three new products in an ongoing series were released last week by the U.S. Geological Survey — including a collection of videos and photos of the seafloor in waters along the entire California coast.

The USGS is a key partner in the California Seafloor Mapping Program — a collaboration between state and federal agencies, academia, and the private sector to create a comprehensive base-map series for all of California’s ocean waters.

Scientists are collecting sonar data, video and photographic imagery, seismic surveys and bottom-sediment data to create a series of maps of seafloor bathymetry, habitats, geology and more, in order to inform coastal managers and planners, government entities and researchers.

With the new maps, decision-makers and elected officials can better design and monitor marine reserves, evaluate ocean energy potential, understand ecosystem dynamics, recognize earthquake and tsunami hazards, regulate offshore development and improve maritime safety.

“The Ocean Protection Council recognized early on that seafloor habitats and geology were a fundamental data gap in ocean management,” said California’s Secretary for Natural Resources and Ocean Protection Council Chair John Laird. “After an impressive effort by many partners to collect and interpret the data, the maps being produced now are providing pioneering science that’s changing the way we manage our oceans.”

The heart of the USGS California Seafloor Mapping Program effort is a series of map sets. To date, three sets have been published. The maps are created through the collection, integration, interpretation and visualization of swath sonar data, acoustic backscatter, seafloor video, seafloor photography, high-resolution seismic-reflection profiles and bottom-sediment sampling data.

Fourteen other map sets are being formatted for publication; the California State Waters Map Series is planned to comprise 83 such seafloor map sets spanning the entire coast of California.

—Pat Sherman

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