This data release includes marine geophysical data collected on cruise B-05-11-CC between Point Sur and Morro Bay, California. The overall goal of this research is to understand the shallow geologic framework of this area as a contribution to the California Seafloor Mapping Program (Johnson and others, 2017). Particular focus is on mapping active faults and documenting the distribution and thickness of offshore, unconsolidated sediment. Approximately 700 km of single-channel, seismic-reflection data between Point Sur and Morro Bay were collected during the cruise. Seismic profiles were collected at 1 km line spacing between Point Sur and Piedras Blancas, crossing the Hosgri-San Gregorio fault system 60 times. Data were also collected to the south on the south flank of Piedras Blancas (south of San Simeon) crossing the Hosgri-San Gregorio fault 13 times at 800 m line spacing. Farther south, additional data were collected offshore of Morro Bay with a focus on crossing the Los Osos fault zone. Data collected in the southern two areas overlap with and supplement data available in Sliter and others (2009). 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 1600 Hz. At boat speeds of 4 to 4.5 nm/hour, seismic traces were collected roughly every 1 to 2 meters. Water depths were between 20 m and 600 m. Acoustic pulses were generated at 0.5-second intervals on profiles where maximum depth was about 300 m; a 1-second interval was used on the deeper water profiles. 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), and SeismicUnix developed at the Colorado School of Mines. 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 (corrected) data are provided here.
header: fno 0 lno 9999999 ftr 0 ltr 99999 l4 = l3 header2: fno 0 lno 99999 ftr 0 ltr 99999 r59 = r50 filter: ftype 0 pass 160 1600 water bottom picker: solrat between 2-5 ses 0 0.002 sel 0 0.5 swell: n 35
Are there legal restrictions on access or use of the data?
Use_Constraints:USGS-authored or produced data and information are in the public domain from the U.S. Government and are freely redistributable with proper metadata and source attribution. Please recognize and acknowledge the U.S. Geological Survey as the originator(s) of the dataset and in products derived from these data. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. This information is not intended for navigational purposes.
Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty.
|Data format:||Zip file contains the raw and swell-corrected seismic data per navigation line in format SEG-Y (version SEG-Y rev 1) Size: 19196|