Archive of Digital Boomer Subbottom Data Collected During USGS Cruises 99FGS01 and 99FGS02 Offshore Southeast and Southwest Florida, July and November, 1999
Geospatial_Data_Presentation_Form: Tabular, vector, and raster digital data
During July 19 - 26 and November 17 - 18 of 1999, the U.S. Geological Survey (USGS), in cooperation with the Florida Geological Survey (FGS), conducted geophysical surveys of the Atlantic Ocean offshore of Florida's southeast coast from Orchid to Jupiter, FL and the Gulf of Mexico offshore of Venice, FL. This report serves as an archive of unprocessed digital boomer subbottom data, trackline maps, navigation files, GIS information, and formal FGDC metadata. Filtered and gained digital images of the subbottom profiles are also provided. The archived trace data are in standard Society of Exploration Geophysicists (SEG) SEG Y revision 0 format (Barry and others, 1975) and may be downloaded and processed with commercial or public domain software such as Seismic Unix (SU). Example SU processing scripts and USGS software for viewing the SEG Y files (Zihlman, 1992) are also provided.
These data are also available for viewing using GeoMapApp (<http://www.geomapapp.org/>) and Virtual Ocean (<http://www.virtualocean.org/>) multi-platform open source software. In addition to this DVD, the SEG Y files can also be downloaded from the USGS Coastal and Marine Geoscience Data System (<http://cmgds.marine.usgs.gov>).
Purpose:
The data archived here were collected under a cooperative agreement between the Florida Geological Survey and the USGS.
Supplemental_Information:
The USGS Saint Petersburg Coastal and Marine Science Center (SPCMSC) - St. Petersburg, FL, assigns a unique identifier to each cruise or field activity. For example, 99FGS01 and 99FGS02 tells us the data were collected in 1999 for the Florida Geological Survey (FGS) cooperative agreement and the data were collected during the first and second field activities for that project in that calendar year. Refer to <http://walrus.wr.usgs.gov/infobank/programs/html/definition/activity.html> for a detailed description of the method used to assign the cruise ID.
The boomer subbottom processing system consists of an acoustic energy source that is made up of capacitors charged to a high voltage and discharged through a transducer in the water. The transducer is towed on a sled floating on the water surface and when discharged emits a short acoustic pulse, or shot, that propagates through the water column and shallow stratigraphy below. The acoustic energy is reflected at density boundaries (such as the seafloor or sediment layers beneath the seafloor), detected by the receiver (hydrophone streamer), and recorded by a PC-based seismic acquisition system. This process is repeated at timed intervals (for example, 0.5 s) and recorded for specific intervals of time (for example, 100 ms). In this way, a 2-D vertical image of the shallow geologic structure beneath the ship track is produced.
An Applied Acoustic Engineering CSP 300 provided 300 Joules of energy per shot. Reflected energy was received by a Innovative Transducers, Inc. (ITI) ST-5 10-channel streamer and recorded by Triton Elics International, Inc. (TEI) Delph Seismic v. 1.36 acquisition software. The streamer contains 10 hydrophones evenly spaced every 0.60 m. The streamer was positioned directly behind the research vessel (parallel to the boomer sled), with a lateral separation of approximately 14 m (99FGS01) and 24 m (99FGS02). Refer to figure 2 included with this archive for a diagram of the acquisition geometries. The sample frequencies of the data were 240-2400 Hz and 8000 Hz, and record length was 100 ms. The shot spacing was highly variable; however, based on survey speeds of 3 knots and a shot rate of every 1 s, shot spacing was about 1.54 m.
The unprocessed seismic data are stored in SEG Y rev. 0, integer, Motorola format, which is a standard digital format that can be read and manipulated by most seismic processing software packages (Barry and others, 1975). The SEG Y formatted trace files have a .TRA extension. The printable profiles provided here are GIF images that were filtered and gained using Seismic Unix software.
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 19990719, 19991117
Ending_Date: 19990726, 19991118
Currentness_Reference: Data collection interval
Status:
Progress: Complete
Maintenance_and_Update_Frequency: None planned
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -82.809167
East_Bounding_Coordinate: -79.949167
North_Bounding_Coordinate: 27.099167
South_Bounding_Coordinate: 26.968056
Keywords:
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Topic Category
Theme_Keyword: geoscientificinformation
Theme_Keyword: oceans
Theme:
Theme_Keyword_Thesaurus: General
Theme_Keyword: Geology
Theme_Keyword: Coastal information
Theme_Keyword: Marine
Theme_Keyword: Subbottom profile
Theme_Keyword: Seismic reflection
Theme_Keyword: Boomer
Theme_Keyword: Society of Exploration Geophysicists
Theme_Keyword: SEG Y
Theme_Keyword: Florida Geological Survey
Theme_Keyword: FGS
Theme_Keyword: 99FGS01
Theme_Keyword: 99FGS02
Place:
Place_Keyword_Thesaurus: Geographic Names Information System (GNIS) Content
Place_Keyword: United States of America
Place_Keyword: Florida
Place_Keyword: Atlantic Ocean
Place_Keyword: Gulf of Mexico
Place_Keyword: Orchid
Place_Keyword: Fort Pierce
Place_Keyword: Stuart
Place_Keyword: Sebastian Inlet
Place_Keyword: Jupiter
Place_Keyword: Venice
Access_Constraints: None. These data are held in the public domain.
Use_Constraints:
The U.S. Geological Survey and Florida Geological Survey (FGS) request to be acknowledged as originators of the data in future products or derivative research.
Location map of digital boomer subbottom data collected during USGS Field Activities 99FGS01 and 99FGS02. This map was created at a scale of 1:442,800. Refer to the Lineage section below for the trackline map creation process.
Location map of digital boomer subbottom data collected during USGS Field Activity 99FGS01. This map was created at a scale of 1:654,650. Refer to the Lineage section below for the trackline map creation process.
Location map of digital boomer subbottom data collected during USGS Field Activity 99FGS02. This map was created at a scale of 1:239,600. Refer to the Lineage section below for the trackline map creation process.
Directory containing printable images of all subbottom profiles.
Browse_Graphic_File_Type: GIF
Data_Set_Credit:
Funding and (or) support for this study was provided by the USGS Coastal and Marine Geology Program and FGS. This document was improved by the reviews of Ellen Raabe (USGS) and Theresa Burress (Cherokee Nation Technology Solutions) of the USGS - St. Petersburg, FL.
Disc Image Credit: Schmaltz, Jeff, MODIS Rapid Response Team at the NASA Goddard Space Flight Center, 2004, UnitedStates.A2004106.1855.500m.jpg. Also available on-line at <http://eoimages.gsfc.nasa.gov/ve/6886/UnitedStates.A2004106.1855.500m.jpg>
Cross_Reference:
Citation_Information:
Originator: Cohen, J.K., and Stockwell, J.W., Jr., CWP/SU
Publication_Date: 2010
Title:
Seismic Unix Release 41: A free package for seismic research and processing, Center for Wave Phenomena, Colorado School of Mines
The validity or accuracy of marine subbottom profiles is highly qualitative and depends on equipment and operating condition variables. Visual inspection of the images rendered from the data did not show any major anomalies.
Logical_Consistency_Report:
This dataset is from one field activity with consistent instrument calibrations.
Completeness_Report:
These data are collected along tracklines (2-D) and are therefore inherently incomplete. Geologic details between lines must be inferred.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
As the subbottom data were acquired, the position of the vessel was continuously determined by a Trimble Centurion GPS receiver, which is accurate within 3 - 5 m. Positions were recorded and written to the trace headers in latitude and longitude coordinates about every 1 s. The approximately 25-m offset between the Boomer shot and GPS was not accounted for during acquisition nor have the ASCII navigation files and trackline map been corrected to reflect the offset. NOTE: The navigation data written to the "Source coordinates" of the SEG Y trace headers (bytes 73 - 80) are only accurate within 1 s of arc, or about 31 m. Additional navigation data were recorded more accurately (between 3 - 5 m) to the "Unassigned" trace headers (bytes 181 - 240) by the Delph Seismic acquisition software. These navigation files were not used to produce the trackline maps. Please see the SEG Y Format page for a detailed description of the SEG Y data format including byte number assignments and header value descriptions. The Delph Seismic navigation data can be accessed from the Navigation page under the Raw Shotpoint Navigation section or via the delphnav folder.
Vertical_Positional_Accuracy:
Vertical_Positional_Accuracy_Report:
Boomer data are relative to sea level. However, varying recorded static shifts of the data have been known to occur. Therefore, these data are not to be used for bathymetry.
Lineage:
Process_Step:
Process_Description:
Boomer processing: Using Seismic Unix software, the data were first converted to SU format (in doing so all the undefined header fields were zeroed) and then the SEG Y data were processed to produce GIF images of the subbottom profiles included in this report. A representative boomer processing sequence consisted of (1) running a bandpass filter of 300-500-2500-3000 Hz, (2) applying automatic gain control, (3) displaying PostScript, and (4) converting of PostScript image to a GIF image.
Navigation processing: Shotpoint navigation, start of line, and 500-shot-interval location files were extracted using Seismic Unix software and output as ASCII text files; they were then processed with PROJ.4.7.0 (<http://trac.osgeo.org/proj/>) to generate UTM coordinates from latitude and longitude coordinates. Text files for each seismic line were concatenated into comma-delimited text files (for use with ESRI software), containing unique shotpoint positions (99fgs01.txt and 99fgs02.txt), the 500-shot-interval locations (s99fgs01.txt and s99fgs02) and start of line locations (99fgs01_s and 99fgs02_s); all files can be viewed within the nav folder of this report.
Source_Used_Citation_Abbreviation: b**.txt, m**.txt, ir*.txt, and sl*.txt; grecon*.txt
All concatenated, comma-delimited text files were imported into ArcGIS and saved as either a point or polyline file in the ESRI shapefile format.
Trackline map creation: The trackline maps were created using ESRI ArcGIS 10 software. The processed navigation files, 99fgs01.txt and 99fgs01.txt, were imported into ArcMap 10 and processed using the Points to Lines ArcScript to create a line shapefile of the cruise tracklines (99fgs01_trkln and 99fgs02_trkln). The 500-shot-interval files s99fgs01.txt and s99fgs02.txt and the start of line files 99fgs01_s.txt and 99fgs02_s.txt were imported into ArcMap as point shapefiles 99fgs01_shots, 99fgs02_shots, 99fgs01_sol, and 99fgs02_sol. Please refer to the shapefile metadata included in the ArcGIS map document located under the Software section of this archive for additional details. The location maps were exported to Adobe Illustrator v. 14 for further editing then later converted into JPEG format by Adobe Dreamweaver v. 10 Build 4117. The map is unprojected (geographic coordinates, WGS84). The USGS is the originator of all layers used. Please see the ArcGIS readme file for detailed information about the GIS files used in this report.
Data Series preparation: In addition to the process steps described above, the following steps were taken to produce this Data Series report: the handwritten (<https://pubs.usgs.gov/ds/773/logbooks/handwritten/>) cruise logs were scanned and saved as a PDF file, digital (<https://pubs.usgs.gov/ds/773/logbooks/digital/>) logs were created by A. Forde using the cruise logs and personal accounts of the crew members and saved as PDF files, and an HTML-based format was used to present the various parts of this archive.
Horizontal X and Y locations (latitude and longitude and Zone 17 UTM coordinates) for each shot are provided as ASCII text files, along with the date and time (UTC) the shot was recorded.
Sequential unique whole numbers that are automatically generated.
Attribute:
Attribute_Label: Shape*
Attribute_Definition: Feature geometry.
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Unrepresentable_Domain: Coordinates defining the features.
Attribute:
Attribute_Label: UTMX
Attribute_Definition: UTM-X coordinate (Zone 17)
Attribute_Definition_Source: Universal Transverse Mercator Geographic Coordinate System
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 485419
Range_Domain_Maximum: 516280
Attribute_Units_of_Measure: meters
Attribute:
Attribute_Label: UTMY
Attribute_Definition: UTM-Y coordinate (Zone 17)
Attribute_Definition_Source: Universal Transverse Mercator Geographic Coordinate System
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 3228278
Range_Domain_Maximum: 3280044
Attribute_Units_of_Measure: meters
Attribute:
Attribute_Label: Line
Attribute_Definition: Trackline number
Attribute_Definition_Source: U.S. Geological Survey
Attribute_Domain_Values:
Unrepresentable_Domain:
Individual line name for all lines collected during 99FGS01 and 99FGS02.
Attribute:
Attribute_Label: Shot
Attribute_Definition: Shotpoint number
Attribute_Definition_Source: U.S. Geological Survey
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 1
Range_Domain_Maximum: 20000
Attribute:
Attribute_Label: Lon
Attribute_Definition: Longitude (decimal degrees)
Attribute_Definition_Source: World Geodetic System 1984 Geographic Coordinate System
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -81.15062
Range_Domain_Maximum: -80.832379
Attribute_Units_of_Measure: decimal degrees
Attribute:
Attribute_Label: Lat
Attribute_Definition: Latitude (decimal degrees)
Attribute_Definition_Source: World Geodetic System 1984 Geographic Coordinate System
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 29.183103
Range_Domain_Maximum: 29.650282
Attribute_Units_of_Measure: decimal degrees
Attribute:
Attribute_Label: YEAR
Attribute_Definition: Year
Attribute_Definition_Source: U.S. Geological Survey
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 1999
Range_Domain_Maximum: 1999
Attribute:
Attribute_Label: DOY:HR:MIN:SEC
Attribute_Definition: Day of year:hour:minute:second
Attribute_Definition_Source: U.S. Geological Survey
Attribute_Domain_Values:
Unrepresentable_Domain: Day of year, hour, minute and second of data acquisition
Overview_Description:
Entity_and_Attribute_Overview:
Binary data file: Trace data are available as binary files in SEG Y format. These files have a .TRA extension and range in size from 2.22 to 28.9 MB (99FGS01) and 15.9 - 49.7 (99FGS02) MB. These data can be found by going to <https://pubs.usgs.gov/ds/773/segy/>
Entity_and_Attribute_Overview:
Graphic image file: Printable versions of the subbottom profiles are available as GIF images, links to these images can be found on the Profiles page or by going to <https://pubs.usgs.gov/ds/773/profiles/printable/>.
Entity_and_Attribute_Overview:
Navigation file: Navigation files are available as ASCII text files. Provided are raw (unprocessed) shotpoint navigation files, processed shotpoint navigation (99fgs01.txt and 99fgs02.txt), processed 500-shot-interval location (s99fgs01.txt and s99fgs02.txt), and a start of line file (99fgs01_s.txt and 99fgs02_s.txt). Fields/Attributes [FID, Shape] marked above with an asterisk (*) were created by ESRI ArcGIS and are used exclusively by the shapefiles created from the aforementioned .txt files; these fields are not included in the original navigation files. All remaining attributes listed in the above section that do not have an accompanying asterisk are found in 99fgs01.txt, 99fgs02.txt, s99fgs01.txt, s99fgs02.txt, 99fgs01_s.txt, and 99fgs02_s.txt. Raw and processed navigation data files can be found by going to <https://pubs.usgs.gov/ds/773/nav/>.
Entity_and_Attribute_Overview:
GIS file: The GIS project used to create the trackline maps is provided as a .zip file composed of ESRI map documents, shapefiles, and metadata.
Entity_and_Attribute_Detail_Citation: Information is derived from SEG Y headers.
All of this report is available online. The SEG Y files are downloadable from the Coastal and Marine Geoscience Data System (<http://cmgds.marine.usgs.gov>).
Resource_Description: U.S. Geological Survey Data Series 773
Distribution_Liability:
This DVD publication was prepared by an agency of the United States Government. Although these data have been processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made regarding the display or utility of the data on any other system, nor shall the act of distribution imply any such warranty. The U.S. Geological Survey shall not be held liable for improper or incorrect use of the data described and (or) contained herein. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof.
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Format_Name: SEG Y rev. 0
Format_Information_Content:
The SEG Y standard format (Barry and others, 1975) consists of the following: a 3,600-byte reel identification header, with the first 3,200 bytes consisting of an ASCII header block followed by a 400-byte binary header block, both of which include information specific to line and reel number; a trace data block that follows the reel identification header, with the first 240 bytes of each trace block consisting of the binary trace identification header; and seismic data samples that follow the trace identification header.
File_Decompression_Technique: None
Transfer_Size: 463 MB (99FGS01) and 165 MB (99FGS02)
Digital_Transfer_Option:
Offline_Option:
Offline_Media: DVD
Recording_Format: ISO 9660
Compatibility_Information: Unix, Linux, DOS, Macintosh
Digital_Form:
Digital_Transfer_Information:
Format_Name: map document, shapefile, metadata
Format_Information_Content:
The GIS project used to create the trackline maps is composed of map documents, shapefiles, and metadata. Map documents were created with ESRI ArcGIS 10 software. The shapefiles provided may also be viewed using other versions of ESRI desktop software including their free software ArcGIS Explorer (<http://www.esri.com/software/arcgis/explorer/>).
Fees: None, if obtained online; otherwise, prices vary.
Ordering_Instructions:
Publications are available from USGS Information Services, Box 25286, Federal Center, Denver, CO 80225-0046 (telephone: 1-888-ASK-USGS, e-mail: infoservices@usgs.gov).
Technical_Prerequisites:
Use of SEG Y data requires specialized seismic processing software, such as public domain software Seismic Unix (<http://www.cwp.mines.edu/cwpcodes/>).
