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High-Resolution Seismic-Reflection and Marine Magnetic Data Along the Hosgri Fault Zone, Central California

Ray W. Sliter·Peter J. Triezenberg·Patrick E. Hart·Janet T. Watt·Samuel Y. Johnson·Daniel S. Scheirer
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Abstract

The U.S. Geological Survey (USGS) collected high-resolution shallow seismic-reflection and marine magnetic data in June 2008 in the offshore areas between the towns of Cayucos and Pismo Beach, Calif., from the nearshore (~6-m depth) to just west of the Hosgri Fault Zone (~200-m depth). These data are in support of the California State Waters Mapping Program and the Cooperative Research and Development Agreement (CRADA) between the Pacific Gas & Electric Co. and the U.S. Geological Survey. Seismic-reflection and marine magnetic data were acquired aboard the R/V Parke Snavely, using a SIG 2Mille minisparker seismic source and a Geometrics G882 cesium-vapor marine magnetometer. More than 550 km of seismic and marine magnetic data was collected simultaneously along shore-perpendicular transects spaced 800 m apart, with an additional 220 km of marine magnetometer data collected across the Hosgri Fault Zone, resulting in spacing locally as smallas 400 m. This report includes maps of the seismic-survey sections, linked to Google Earth software, and digital data files showing images of each transect in SEG-Y, JPEG, and TIFF formats, as well as preliminary gridded marine-magnetic-anomaly and residual-magnetic-anomaly (shallow magnetic source) maps.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 35° to 35.5° latitude; -121.08333333333333° to -120.58333333333333° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Ray W. Sliter, Peter J. Triezenberg, Patrick E. Hart, Janet T. Watt, Samuel Y. Johnson, Daniel S. Scheirer. 2009. High-Resolution Seismic-Reflection and Marine Magnetic Data Along the Hosgri Fault Zone, Central California. https://doi.org/10.3133/ofr20091100

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