Dataset description: Faults--Offshore of Half Moon Bay Map Area, California

This part of DS 781 presents data for faults for the geologic and geomorphic map of the Offshore of Half Moon Bay map area, California. The vector data file is included in "Faults_OffshoreHalfMoonBay.zip," which is accessible from https://pubs.usgs.gov/ds/781/OffshoreHalfMoonBay/data_catalog_OffshoreHalfMoonBay.html. These data accompany the pamphlet and map sheets of Cochrane, G.R., Dartnell, P., Greene, H.G., Johnson, S.Y., Golden, N.E., Hartwell, S.R., Dieter, B.E., Manson, M.W., Sliter, R.W., Ross, S.L., Watt, J.T., Endris, C.A., Kvitek, R.G., Phillips, E.L., Erdey, M.D., Chin, J.L., and Bretz, C.K. (G.R. Cochrane and S.A. Cochran, eds.), 2014, California State Waters Map Series-Offshore of Half Moon Bay, California: U.S. Geological Survey Open-File Report 2014–1214, pamphlet 37 p., 10 sheets, scale 1:24,000, https://doi.org/10.3133/ofr20141214. Faults in the Offshore of Half Moon Bay map area are identified on seismic-reflection data based on abrupt truncation or warping of reflections and (or) juxtaposition of reflection panels with different seismic parameters such as reflection presence, amplitude, frequency, geometry, continuity, and vertical sequence. Faults were primarily mapped by interpretation of seismic reflection profile data (see field activities S-15-10-NC and F-2-07-NC). The seismic reflection profiles were collected in 2007 and 2010.
Version1
Keywordssea-floor characteristics, structural geology, faulting (geologic), geologic structure, geospatial datasets, maps and atlases, marine geology
Data typesSub Bottom Profiler, Sparker
Formatshapefile;
Amount0.1 MB

Contacts

Activities and equipment

ActivityEquipment
S1510NCsparker
shallow-penetrating continuous seismic profiling (3.5-khz system, 150-joule sparker)
F207NC512 chirp
is a seismic reflection instrument that uses sound to examine the layering of sedimentary strata on and below the sea floor. The Chirp being used in this project is a modified version of the Subscan 512 made by Edgetech. The noise it makes actually sounds like a bird's chirp; the frequencies of the sound it produces are between 500 Hz and 12 kHz. The Chirp has two advantages that allow it to get excellent penetration (meaning it can see deep, like >50 m or >64 ft, into the seabed) and high resolution (meaning it can make out fine layering, layers
F207NCsparker
shallow-penetrating continuous seismic profiling (3.5-khz system, 150-joule sparker)