Metadata: Identification_Information: Citation: Citation_Information: Originator: Gina M. Brewer Originator: Shawn V. Dadisman Originator: Jack L. Kindinger Originator: Dana S. Weise Originator: James G. Flocks Publication_Date: 2001 Title: Archive of Boomer Seismic Reflection Data, collected on USGS Cruise 99ASR01, Lake Okeechobee, Florida, 29 June - 30 June, 1999. Geospatial_Data_Presentation_Form: Seismic Reflection Profile Section Series_Information: Series_Name: U.S. Geological Survey Open-File Report Issue_Identification: OFR-01-165 Publication_Information: Publication_Place: St. Petersburg, FL Publisher: U.S. Geological Survey Online_Linkage: http://pubs.usgs.gov/of/2001/of01-165/ Description: Abstract: This report consists of two-dimensional marine seismic reflection profile data from Lake Okeechobee, Fla., that were acquired in June of 1999 aboard the R/V G. K. Gilbert. These data are available in a variety of formats, including binary, ASCII and GIF images. Binary data are in Society of Exploration Geophysicists (SEG) SEG-Y format and may be downloaded for further processing or display. For more information on the seismic surveys see http://walrus.wr.usgs.gov/infobank/g/g399fl/html/g-3-99-fl.meta.html These data are also available via GeoMapApp (http://www.geomapapp.org/) and Virtual Ocean (http://www.virtualocean.org/) earth science exploration and visualization applications. Purpose: Marine seismic reflection data are used to image and map sedimentary and structural features of the seafloor and subsurface. The main objective of this cruise was to ascertain if data useful to the Everglades Aquifer Storage and Recovery Project could be acquired using seismic techniques. These data proved to be useful in mapping the extent and thickness of shallow sedimentary units beneath Lake Okeechobee, Fla., and in assessing other submarine geologic characteristics and features. Supplemental_Information: Seismic reflection profiles are acquired by means of an acoustic source (usually generated electronically), and a hydrophone or hydrophone array. Both elements are typically towed in the water behind a survey vessel. The sound source emits a short acoustic pulse, which propagates through the water and sediment columns. The acoustic energy is reflected at density boundaries (such as the seafloor or sediment layers beneath the seafloor), and detected at the hydrophone. This process is repeated at intervals ranging between 100 ms and 1 s depending on the source type. In this way a two-dimensional image of the geologic structure beneath the ship track is constructed. Seismic data are stored in SEG-Y format, which is a standard digital format that can be read and manipulated by most seismic-processing software packages. The SEG-Y file format includes a 3200-byte descriptive header that contains detailed information regarding the data acquisition and processing parameters. All data presented here are stored in SEG-Y, Integer, Motorola format. The SEG-Y formatted trace data files have a .tra extension. Additional recording parameters for each seismic data file can also be found in the .par file associated with each .tra file. However, the .par files and the cent_rmc.pln file are only needed to replay the data with Triton Elics Delph Seismic software. The seismic energy source employed here was a boomer transducer towed on a sled at the lake surface providing 200 joules per shot. The reflected energy was received by an Innovative Transducer Inc. (ITI) solid core streamer and recorded by PC-based Triton Elics Delph Seismic acquisition software. The ITI streamer contains 10 hydrophones evenly spaced over 6 meters, however only data received by elements 5-8 where summed, resulting in a higher signal to noise ratio for the data. The streamer was positioned parallel to the boomer sled and laterally separated from it by 7 m. The sled was towed 20 m behind the Global Positioning System (GPS) antennae. The sample frequency of the data was 16000 Hz and the total record length was 200 ms for tracklines oke699_1 to oke699_7 and 300 ms for tracklines oke699_8 to oke69911. The fire rate was every 0.5 s, which resulted in a shot spacing of about 1 m based on survey speeds of 3.5-4 knots. GPS navigation was provided by a Trimble Centurian P-Code receiver directly fed to the acquisition system. The shotpoint navigation provided in this report has not been corrected to reflect the 20 m offset of the source to the GPS antenna. The horizontal accuracy of the navigation data was within 31m. The navigation data are stored as flat ASCII files. The raw navigation files were generated by the Delph Seismic Software for each trackline and provide the following information for each unique position fix, all separated by commas: shotpoint number, longitude, latitude, heading, speed, date, and Greenwich Mean Time(GMT). The edited navigation file contains all the unique fixes for each trackline with spurious points removed. A separate file containing edited navigation for every 500th shotpoint interval is also provided. Both the edited navigation and the 500th shotpoint navigation files contain six fields separated by commas: shotpoint number, date, GMT, longitude, latitude, and the trackline number. This navigation data can be used to plot trackline maps of the seismic profiles at any scale or map projection desired. The trackline map provided on this disc is a Mercator projection and was created with ESRI's GIS software ArcView 3.2. The map was then exported to Adobe Illustrator and saved as a GIF image. This GIF image is viewable with your WWW browser. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 19990629 Ending_Date: 19990630 Currentness_Reference: Data assumed to be constant over time but may change due to geologic processes. Status: Progress: Complete Maintenance_and_Update_Frequency: None Planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -80.834383 W East_Bounding_Coordinate: -80.72581 W North_Bounding_Coordinate: +27.19386 N South_Bounding_Coordinate: +27.11907 N Keywords: Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:978d0f75-4b39-4b5d-b39f-81e453a1dc09 Theme: Theme_Keyword_Thesaurus: none Theme_Keyword: marine seismic reflection Theme_Keyword: boomer Theme_Keyword: 99ASR01 Theme_Keyword: ISO 9660 CD-ROM Theme_Keyword: SEG-Y Theme_Keyword: Aquifer Storage and Recovery Theme: Theme_Keyword_Thesaurus: Data Categories for Marine Planning Theme_Keyword: distributions Theme_Keyword: substrate Theme: Theme_Keyword_Thesaurus: Marine Realms Information Bank (MRIB) Keywords Theme_Keyword: seismic reflection Theme_Keyword: marine geophysics Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: seismic reflection methods Theme_Keyword: sub-bottom profiling Theme_Keyword: marine geophysics Place: Place_Keyword_Thesaurus: none Place_Keyword: Lake Okeechobee Place_Keyword: Florida Place_Keyword: Everglades Place_Keyword: Martin County Place_Keyword: Okeechobee County Place_Keyword: Glades County Access_Constraints: None. These data are held in the public domain. Use_Constraints: The U.S. Geological Survey requests to be acknowledged as the originator of the data in future products or derivative research. Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Jack Kindinger Contact_Organization: U.S. Geological Survey Contact_Position: Oceanographer Contact_Address: Address_Type: mailing address Address: 600 Fourth Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: (727)803-8747 X3018 Contact_Electronic_Mail_Address: jkindinger@usgs.gov Browse_Graphic: Browse_Graphic_File_Name: http://pubs.usgs.gov/of/2001/of01-165/MAPS/okeemap.GIF Browse_Graphic_File_Description: Map of trackline data collected on USGS Cruise 99ASR01, in June of 1999, in Lake Okeechobee, Fla. This map is a mercator projection prepared in ESRI's ArcView 3.2, exported to Adobe Illustrator for further editing and then saved as a GIF image. Browse_Graphic_File_Type: GIF Data_Set_Credit: We thank Keith Ludwig, captain of the R/V G. K. Gilbert for his help in the data collection; Dave Foster and Jenna Hill, of the USGS Seafloor Mapping Group in Woods Hole, Mass., for providing examples of their archives; Jon Childs with the USGS in Menlo Park, Calif., who provided examples of his formal metadata; and Trent Faust and Rob Wertz with the USGS here in St.Petersburg, Fla., for their help in the web design and technical layout of the CD-ROM. Native_Data_Set_Environment: SEG-Y Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: The validity or accuracy of marine seismic reflection 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 data set is from a single cruise with consistent instrument calibrations. Completeness_Report: These data are collected along tracklines (2D). Therefore, data are inherently incomplete. Geologic details between lines must be inferred. Tracklines oke699_1 to oke699_7 were recorded to 200 ms. Tracklines oke699_8 to oke69911 were recorded to 300 ms. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: The position accuracy was determined with a Trimble Centurian P-Code Receiver. Absolute position accuracy was within 31 m. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: The vertical position was lake level and there has been no corrections to a datum or for tidal variations. Lineage: Process_Step: Process_Description: Boomer processing: Raw SEG-Y data was processed with SU to produce the GIF formatted seismic profiles included in this report. A representative data processing sequence consisted of: 1)Bandpass filter: 300-500-2500-3000 Hz; 2)Automatic gain control; 3)Postscript display at 50 ms/in and 300 shots/in for tracklines oke699_1 to oke699_7 and at 75 ms/in and 300 shots/in for tracklines oke699_8 to oke699_11; 4)Convert Postscript files to GIF format Process_Date: 2001 Process_Step: Process_Description: Positional (navigation) data: As the seismic reflection data were acquired, the position of the vessel was determined continuously with the Global Positioning System (GPS). GPS positions were recorded approximately every second, and written to the SEG-Y header. The ASCII navigation files were extracted from the SEG-Y headers using SU scripts and edited for obvious spurious data values. Process_Date: 2001 Process_Step: Process_Description: Open File preparation: No processing has been done to the SEG-Y data files provided on this CD-ROM. The data were displayed as 8-bit gray scale Postscript files using the Seismic Unix 'psimage' algorithm. The Postscript images were then converted to GIF images with Aladdin Ghostscript. Only the GIF images are presented here. Process_Date: 2001 Process_Step: Process_Description: Keywords section of metadata optimized for discovery in USGS Coastal and Marine Geology Data Catalog. Process_Date: 20170124 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Alan O. Allwardt Contact_Position: Contractor -- Information Specialist Contact_Address: Address_Type: mailing and physical address Address: 2885 Mission Street City: Santa Cruz State_or_Province: CA Postal_Code: 95060 Contact_Voice_Telephone: 831-460-7551 Contact_Facsimile_Telephone: 831-427-4748 Contact_Electronic_Mail_Address: aallwardt@usgs.gov Process_Step: Process_Description: Added keywords section with USGS persistent identifier as theme keyword. Process_Date: 20201013 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: VeeAnn A. Cross Contact_Position: Marine Geologist Contact_Address: Address_Type: Mailing and Physical Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Contact_Voice_Telephone: 508-548-8700 x2251 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: vatnipp@usgs.gov Spatial_Data_Organization_Information: Indirect_Spatial_Reference: Horizontal X and Y locations for each shot location are provided in ASCII position files, along with the time the shot was recorded in Greenwich Mean Time (GMT). Direct_Spatial_Reference_Method: Point Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Geographic: Latitude_Resolution: 0.000278 Longitude_Resolution: 0.000278 Geographic_Coordinate_Units: Decimal degrees Geodetic_Model: Horizontal_Datum_Name: WGS 84 Ellipsoid_Name: WGS 1984 Semi-major_Axis: 6378137 m Denominator_of_Flattening_Ratio: 298.257 Entity_and_Attribute_Information: Overview_Description: Entity_and_Attribute_Overview: Binary data file: Each profile is available as a binary file in Society of Exploration Geophysicists SEG-Y format. A SEG-Y file consists of 1) a 3200-byte file identification record of ASCII formatted general information; 2) a 400-byte binary record with information such as sample rate and record length specific to the data set; and 3) multiple records, one seismic reflection trace per record. Each trace record is preceded by a 240-byte "trace header" containing information such as trace number and acquisition day and time specific to each trace. The trace data are represented as a time series of unitless 16-bit integer or 32-bit real numbers proportional to the reflection coefficient. The SEG-Y file is useful only if you have access to specialized software designed to process and display seismic reflection data. These SEG-Y files have a .tra extension. These .tra files range in size from 21 MB to 80 MB. Entity_and_Attribute_Overview: Graphic image file: Each profile is available as a GIF image. The trackline maps provided are GIF images that contain hot-links to the seismic profile GIF images. The profiles range in size from 508KB to 1.9MB. Entity_and_Attribute_Detail_Citation: Barry, K.M., Cavers, D.A., and Kneale, C.W., 1975, Recommended standards for digital tape formats: Geophysics, v. 40, n. 2, p. 344 - 352. Also available online at: Distribution_Information: Distributor: Contact_Information: Contact_Person_Primary: Contact_Person: Rob Wertz Contact_Organization: U.S. Geological Survey Contact_Position: Manager, Data Management Group Contact_Address: Address_Type: mailing address Address: 600 Fourth Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: (727)803-8747 X3045 Contact_Electronic_Mail_Address: rwertz@usgs.gov Contact_Instructions: Data may be available online only by special arrangement with the distributor above. Resource_Description: U.S. Geological Survey Open-File Report 01-XXX CD-ROM Distribution_Liability: This Compact Disc-Read Only Memory (CD-ROM) publication was prepared by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, make any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed in this report, or represents that its use would not infringe privately owned rights. Reference therein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. Any views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Although all data published on this CD-ROM have been used by the USGS, no warranty, expressed or implied, is made by the USGS as to the accuracy of the data and related materials and/or the functioning of the software. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of this data, software, or related materials. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: SEG-Y Format_Information_Content: The SEG-Y standard format (Barry and others, 1975) consists of the following: A 3600-byte reel identification header with the first 3200 bytes consisting of an EBCDIC header block and a 400-byte binary header block. Both headers include information specific to line and reel number. The trace data block follows the reel identification header. The first 240 bytes of each trace block is the binary trace identification header. The seismic data samples follow the trace identification header. Our data uses an ASCII header block instead of the standard EBCDIC. File_Decompression_Technique: none Transfer_Size: 650 Digital_Transfer_Option: Offline_Option: Offline_Media: CD-ROM Recording_Format: ISO 9660 Compatibility_Information: Unix, Linux, DOS, MAC Digital_Form: Digital_Transfer_Information: Format_Name: SEGY data download Format_Information_Content: The SEG-Y standard format (Barry and others, 1975) consists of the following: A 3600-byte reel identification header with the first 3200 bytes consisting of an EBCDIC header block and a 400-byte binary header block. Both headers include information specific to line and reel number. The trace data block follows the reel identification header. The first 240 bytes of each trace block is the binary trace identification header. File_Decompression_Technique: none Transfer_Size: 650 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://cmgds.marine.usgs.gov/data/99asr01/ Fees: available from the Denver Open-File Sales Department, for $50.00. Ordering_Instructions: This archive is stored on an ISO 9660 CD-ROM. Technical_Prerequisites: Use of SEG-Y data requires specialized seismic processing software, such as Unix or Linux based public-domain software Seismic Unix developed by the Colorado School of Mines Center for Wave Phenomena, which can be downloaded from free of charge. Metadata_Reference_Information: Metadata_Date: 20201013 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Gina M. Brewer Contact_Organization: U.S. Geological Survey Contact_Position: Geologist, Data Management Group Contact_Address: Address_Type: mailing address Address: 600 Fourth Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: (727)803-8747 X3120 Contact_Electronic_Mail_Address: gmbrewer@usgs.gov Metadata_Standard_Name: Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998