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Marine geophysical data - Point Sal to Refugio State Beach, southern California

January 4, 2017

This data release includes approximately 1,032 km of marine single-channel seismic-reflection data collected by the U.S. Geological Survey on a research cruise (USGS survey 2014-632-FA) in July and August, 2014, between Point Sal and Refugio State Beach. The dataset includes 168 profiles, most of which were collected on tracklines roughly perpendicular to the coast at 1 km line spacing; additional profiles were collected on coast-parallel tie lines. These data were acquired to support the California Seafloor Mapping Program and USGS Geologic Hazards projects.

Seismic-reflection data were collected using a minisparker system that creates an acoustic signal by discharging an electrical pulse between electrodes and a ground that generates a frequency spectrum roughly between 200 and 1,600 Hz. At boat speeds of 4 to 4.5 nm/hour, seismic traces were collected roughly every 1 to 2 meters. Water depths were generally between 50 m and 150 m, but as shallow as 10 meters near the shoreline, and as deep as 480 m for profiles crossing the Santa Barbara basin. Acoustic pulses were generated at 0.5-second intervals on most profiles; a 1-second interval was used on the few profiles collected in deeper water. Standard SEG-Y files were generated using a Triton Subbottom Logger (SBL). Seismic data processing was accomplished using Sioseis, a public-domain software developed at Scripps Institute of Oceanography (part of the University of California at San Diego). The processing of these data consisted of a bandpass filter, mute function, automatic gain control, water bottom detect, swell correction, and scaling/plotting. Both raw data in SEG-Y format and processed data (Corrected SEG-Y) are provided in this data release.

Publication Year 2017
Title Marine geophysical data - Point Sal to Refugio State Beach, southern California
DOI 10.5066/F7SX6BCD
Authors Samuel Y Johnson, Stephen R. Hartnell, Jeffrey W. Beeson
Product Type Data Release
Record Source USGS Asset Identifier Service (AIS)
USGS Organization Pacific Coastal and Marine Science Center
Rights This work is marked with CC0 1.0 Universal
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