Drake M. Singleton Daniel S. Brothers Jared W. Kluesner Ray W. Sliter 20210518 seismic-reflection data in SEG-Y format data release DOI:10.5066/P93Z2LYJ Pacific Coastal and Marine Science Center, Santa Cruz, California U.S. Geological Survey https://doi.org/10.5066/P93Z2LYJ https://www.sciencebase.gov/catalog/item/604fcb2cd34eb1203122e248 This data release presents reprocessed multichannel seismic-reflection (MCS) data that was originally collected in 1996 in partnership with the California Division of Mines and Geology and Caltrans as part of a seismic hazard assessment of the Coronado Bridge in San Diego Bay, California. The original survey collected 130 km of data with a 14-cubic inch sleeve-gun (airgun) source, a 24-channel streamer, and 3.125 m shot spacing. Reprocessed profiles show increased data resolution, with data recorded to 750 ms two-way-travel-time, and interpretable data down to about 400 m. Data were reprocessed as part of an effort to investigate faulting in south San Diego Bay. Data were used to characterize fault structure, changes in sub-surface stratigraphy, and investigate recency of faulting. Reprocessing scheme included applying a linear moveout, f-k filter, velocity analysis, normal moveout, water bottom mute, stacking, and time migration. These data and information are intended for science researchers, students from elementary through college, policy makers, and general public. Additional information about the field activities from which these data were derived is available online at: http://cmgds.marine.usgs.gov/fan_info.php?fan=T196SC Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. 19960609 19960613 ground condition at time data were collected. Complete None planned -117.230246 -117.097027 32.728142 32.631426 ISO 19115 Topic Category geoscientificinformation oceans Data Categories for Marine Planning Substrate Distributions USGS Thesaurus sub-bottom profiling geospatial datasets marine geophysics Marine Realms Information Bank (MRIB) keywords seismic reflection profiling seabed acoustic methods mapping geophysics USGS Metadata Identifier USGS:f4f9c42d-bdbb-4f24-9be9-e9b394932e08 None U.S. Geological Survey USGS Coastal and Marine Hazards and Resources Program CMHRP Pacific Coastal and Marine Science Center PCMSC Geographic Names Information System (GNIS) San Diego Bay State of California NGA GEOnet Names Server (GNS) San Diego Bay None None None 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, California Division of Mines and Geology, and Caltrans as the originator(s) of the dataset and in products derived from these data. This information is not intended for navigation purposes. U.S. Geological Survey, Pacific Coastal and Marine Science Center PCMSC Science Data Coordinator mailing and physical

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Santa Cruz CA 95060 831-427-4747 pcmsc_data@usgs.gov https://www.sciencebase.gov/catalog/file/get/604fcb2cd34eb1203122e248?name=T-1-96-SC_SDBay_reproc_mcs_tracklines.jpg&allowOpen=true Map of tracklines along which MCS data were collected during USGS field activity T-1-96-SC JPEG SEG-Y rev 1 Identified as best available version No formal logical accuracy tests were conducted, but quality control was conducted during acquisition. Dataset is considered complete for the information presented, as described in the abstract. Users are advised to read the rest of the metadata record carefully for additional details The original survey lines and navigation from 1996 were stored on magnetic tape files that were destroyed in a warehouse fire. The reprocessed profiles in this dataset therefore did not include navigation data in the SEG-Y header. To overcome this, the original trackline map was georeferenced and individual profiles digitized. The total length of these profiles was divided by the 3.125 m gather spacing to produce the profile navigation. As a result of the georeferencing and uncertainty in profile locations on the original figure, the final locations of some profiles may carry a location error of ~10-100 m. Despite this uncertainty, a comparison of previously mapped features in San Diego Bay shows good agreement in the reprocessed MCS lines presented in this dataset. A formal accuracy assessment of the vertical positional information in the data set has not been conducted. The original survey collected 130 km of MCS lines with a 14-cubic inch sleeve-gun (airgun) source, 24-channel streamer, and 3.125 m shot spacing. The original MCS data were stored as 12-fold common-depth-point gathers with 3.125 m bin spacing. Following transcribing of profiles to modern digital format, the originals SEG-Y files were reprocessed through the Shearwater Reveal software package. The original 24-trace shot gathers were sampled at 250 ms with a total length of 0.75 s. Linear moveout and f-k filters were applied to shot gathers to reduce linear coherent noise and energy from refracted arrivals at longer offsets, which were especially prevalent in shallow San Diego Bay and in portions of the bay proximal to large cement structures such as Naval docks. Next, shot gathers were sorted into common-mid-point (CMP) gathers using a 3.125-m bin spacing (12-fold). Velocity analysis was performed every 100 CMPs by maximizing semblance for supergathers constructed using 15 CMPs, and the resulting velocity models were used to apply normal moveout corrections (NMO). Following NMO corrections, water-bottom and stretch-mutes were applied, and the traces were stacked. Lastly, Stolt migration was applied to stacked sections using a constant velocity of 1600 m/s. Navigation is presented in UTM zone 11N in header bytes 73/77 and in 81/85. 20210115 Corrected typo in DOI URL in onlink tag of metadata. No data were changed. (scochran@usgs.gov) 20210823 Horizontal X and Y locations for each seismic profile location are stored in the SEG-Y data trace headers in header bytes 81 and 85. WGS 1984 UTM Zone 11N 0.9996 -117.0 0.0 500000.0 0.0 coordinate pair 0.0001 0.0001 Meter D WGS 1984 WGS 1984 6378137.0 298.257223563 local surface 0.5 two-way travel time attribute values Seismic shots with time stamp in standard SEG-Y file format Society of Exploration Geophysicists (SEG) Technical Standards, available for download at http://seg.org/Publications/SEG-Technical-Standards U.S. Geological Survey - ScienceBase mailing and physical

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Denver CO 80225 1-888-275-8747 sciencebase@usgs.gov T-1-96-SC_SDBay_reproc_mcs.zip contains reprocessed sub-bottom (SEG-Y) data collected during USGS field activity T-1-96-SC. The data are divided up and presented by navigation line, as reflected in the individual file names. 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. SEG-Y SEG-Y rev 1 Zip files contains the processed seismic data per navigation line and are divided based on geographic location. Winzip, 7-zip, or Winrar are free software that will open .zip files 229.91 https://www.sciencebase.gov/catalog/file/get/604fcb2cd34eb1203122e248 https://doi.org/10.5066/P93Z2LYJ Data can be downloaded using the Network_Resource_Name links. The first link is a direct link to download the zipped file of data and metadata. The second link points to a landing page with metadata and data None. Use of SEG-Y data requires specialized software, such as Reveal by Shearwater Geophysical; ProMax and Seisworks by Landmark Geophysical; FOCUS and SeisX by Paradigm Geophysical; SPW by Parallel Geoscience; VISTA by Seismic Image Software; SeiSee by Dalmorneftegeophysica (DMNG); amongst others. 20210823 U.S. Geological Survey, Pacific Coastal and Marine Science Center PCMSC Science Data Coordinator mailing and physical

2885 Mission Street

Santa Cruz CA 95060 831-427-4747 pcmsc_data@usgs.gov Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998