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Identification_Information:

Citation:

††† Citation_Information:

††††† Originator: Gina M. Peery

††††† Originator: Barbara Lidz

††††† Originator: Dana S. Wiese

††††† Publication_Date: 2002

††††† Title: Archive of Boomer Seismic Reflection Data

†††††††††† †††Collected on USGS Cruise 97KEY01,

††††††††††††† Upper and Middle Florida Keys,

††††††††††††† 12 October - 1 November, 1997.

††††† Geospatial_Data_Presentation_Form: Seismic Reflection Profile Section

††††† Series_Information:

††††††† Series_Name: U.S. Geological Survey Open-File Report

††††††† Issue_Identification: 02-421

††††† Publication_Information:

††††††† Publication_Place: St. Petersburg, FL

††††††† Publisher: U.S. Geological Survey

Description:

††† Abstract:

†††† This report consists of two-dimensional marine seismic reflection profile

†††† data from the upper and middle Florida Keys. The area of operations

†††† extended from just north of Molasses Reef off north Key Largo

†††† (Upper Keys) to the east boundary of Looe Key National Marine Sanctuary

†††† (Lower Keys). These data were acquired in October and November of 1997

†††† with the Charter Vessel Captain's Lady. The data are available in a variety

†††† of formats, including binary, ASCII, HTML, Shapefiles, JPG and GIF images.

†††† Binary data are in Society of Exploration Geophysicists (SEG) SEG-Y

†††† format and may be downloaded for further processing or display. Reference

†††† maps and JPG images of the profiles may be viewed with your WWW browser.

††† Purpose:

†††† Marine seismic reflection data are used to image and map sedimentary and

†††† structural features of the seafloor and subsurface. These data are useful

†††† in mapping the extent and thickness of shallow sedimentary units in the

†††† upper and middle Florida Key, and in assessing other submarine geologic

†††† characteristics and features. The main objective of this cruise was to

†††† fill a major gap in the seismic data record. Data had not been collected for

†††† this area at any time during a 20-year study of the reef track.

††† 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 1s 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

†††† plg_gga.pln file are only needed to replay the data with Triton Elics Delph

†††† Seismic software.

†††† The seismic source employed here consisted of a boomer transducer towed

†††† on a sled at the sea surface providing 100 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 GPS antennae. The sample frequency

†††† of the data was 12000 Hz and the total record length was 100 ms. The

†††† fire rate was every 0.25 sec, which resulted in a shot spacing of about

†††† 0.5 m based on survey speeds of 3.5-4 knots.

††††

†††† P-Code GPS navigation was fed to the acquisition system every

†††† second by a Rockwell navigation receiver. The accuracy of this receiver

†††† is within 100 m. However, the data required some editing. A filter was

†††† designed to remove spurious data values and these edited results can be

†††† used to generate trackline maps at any scale or projection desired,

†††† however the shotpoint data has not been corrected to reflect the 20 m

†††† offset between the source and the GPS antenna. Also the raw navigation

†††† files did not have year or julian day written to the headers. This information

†††† was handwritten into the edited and shotpoint navigation files. Position fixes

†††† for every 500th shotpoint and the start and end of line are also provided as

†††† an aide for easy registering of the data after projection. The trackline maps

†††† provided in this report are geographic projections and were created using

†††† ESRI's GIS software ArcView 3.2 and exported to Adobe Illustrator for

†††† further editing, then saved as GIF images. These GIF images are viewable

†††† with your WWW browser. All navigation files are stored as flat ASCII text

†††† files.††

 

†††† Included on this disc are GIS files created with ESRIís Arcview 3.2,

†††† displaying the shotpoint information for each seismic trackline. These

†††† files are compatible with either ArcView 3.x (UNIX or WINDOWS) or

†††† ArcGIS 8.1 (WINDOWS). The files can also be viewed using the Windows

†††† compatible public domain software ArcExplorer 2.0, and 4.0. To download

†††† a free copy of ArcExplorer go to the ESRI website

†††† (http://www.esri.com/software/arcexplorer/).

†††† Field Activity Collection System (FACS) logs are available in both html

†††† and Rich Text format, along with the scanned GIF images of the original

†††† logbooks.

Time_Period_of_Content:

††† Time_Period_Information:

††††† Range_of_Dates/Times:

†††††† Beginning_Date: 19971012

††††††† Ending_Date: 19971101

††† 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: -80.29

††††† East_Bounding_Coordinate:-81.39

††††† North_Bounding_Coordinate:25.15

††††† South_Bounding_Coordinate:24.40

Keywords:

††† Theme:

††††† Theme_Keyword_Thesaurus: none

††††† Theme_Keyword: marine seismic reflection

††††† Theme_Keyword: boomer

††††† Theme_Keyword: 97KEY01

††††† Theme_Keyword: UDF DVD

††††† Theme_Keyword: SEG-Y

††† Place:

††††† Place_Keyword_Thesaurus: none

††††† Place_Keyword: Florida Keys

††††† Place_Keyword: Key Largo

††††† Place_Keyword: Molasses Reef

††††† Place_Keyword: Looe Key National Marine Sanctuary

††††† Place_Keyword: Key Biscayne

††††† Place_Keyword: Biscayne Bay

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: Barbara Lidz

††††††† Contact_Organization: U.S. Geological Survey

††††† Contact_Position: Geologist

††††† 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 X3031

††††† Contact_Electronic_Mail_Address: blidz@usgs.gov

Browse_Graphic:

††† Browse_Graphic_File_Name: DVD/MAPS/fullarea.gif

††† Browse_Graphic_File_Description:

††††† A full survey map of the tracklines collected during

††††† USGS Cruise 97KEY01, in October and November, 1997,

††††† along the upper and middle Florida Keys. This map is a

††††† geographic projection. It was created using ESRIís GIS

††††† software ArcView 3.2, then exported to Adobe Illustrator

††††† for further editing, and saved for the web as a GIF image.

††† Browse_Graphic_File_Type: GIF

Browse_Graphic:

††† Browse_Graphic_File_Name: DVD/MAPS/areaA.gif

††† Browse_Graphic_File_Description:

††††† A survey map of the tracklines collected in Area A during

††††† USGS Cruise 97KEY01, in October and November, 1997,

††††† along the upper and middle Florida Keys. This map is a

††††† geographic projection. It was created using ESRIís GIS

††††† software ArcView 3.2, then exported to Adobe Illustrator

††††† for further editing, and saved for the web as a GIF image.

††† Browse_Graphic_File_Type: GIF

Browse_Graphic:

††† Browse_Graphic_File_Name: DVD/MAPS/areaB.gif

††† Browse_Graphic_File_Description:

††††† A survey map of the tracklines collected in Area B during

††††† USGS Cruise 97KEY01, in October and November, 1997,

††††† along the upper and middle Florida Keys. This map is a

††††† geographic projection. It was created using ESRIís GIS

††††† software ArcView 3.2, then exported to Adobe Illustrator

††††† for further editing, and saved for the web as a GIF image.

††† Browse_Graphic_File_Type: GIF

Browse_Graphic:

††† Browse_Graphic_File_Name: DVD/MAPS/areaC.gif

††† Browse_Graphic_File_Description:

††††† A survey map of the tracklines collected in Area C during

††††† USGS Cruise 97KEY01, in October and November, 1997,

††††† along the upper and middle Florida Keys. This map is a

††††† geographic projection. It was created using ESRIís GIS

††††† software ArcView 3.2, then exported to Adobe Illustrator

††††† for further editing, and saved for the web as a GIF image.

††† Browse_Graphic_File_Type: GIF

Browse_Graphic:

††† Browse_Graphic_File_Name: DVD/MAPS/areaD.gif

††† Browse_Graphic_File_Description:

††††† A survey map of the tracklines collected in Area D during

††††† USGS Cruise 97KEY01, in October and November, 1997,

††††† along the upper and middle Florida Keys. This map is a

††††† geographic projection. It was created using ESRIís GIS

†††† software ArcView 3.2, then exported to Adobe Illustrator

††††† for further editing, and saved for the web as a GIF image.

††† Browse_Graphic_File_Type: GIF

Browse_Graphic:

††† Browse_Graphic_File_Name: DVD/MAPS/areaE.gif

††† Browse_Graphic_File_Description:

††††† A survey map of the tracklines collected in Area E during

††††† USGS Cruise 97KEY01, in October and November, 1997,

††††† along the upper and middle Florida Keys. This map is a

††††† geographic projection. It was created using ESRIís GIS

††††software ArcView 3.2, then exported to Adobe Illustrator

††††† for further editing, and saved for the web as a GIF image.

††† Browse_Graphic_File_Type: GIF

Browse_Graphic:

††† Browse_Graphic_File_Name: DVD/MAPS/areaF.gif

††† Browse_Graphic_File_Description:

††††† A survey map of the tracklines collected in Area F during

††††† USGS Cruise 97KEY01, in October and November, 1997,

††††† along the upper and middle Florida Keys. This map is a

††††† geographic projection. It was created using ESRIís GIS

†† †††software ArcView 3.2, then exported to Adobe Illustrator

††††† for further editing, and saved for the web as a GIF image.

Data_Set_Credit:

††† The USGS Coastal and Marine Geology Program (CMGP)

††† providedthe funding for research east and northeast of the

††† Looe Key National Marine Sanctuary(LKNMS), to Molasses

††† Reef off the upper Keys. Billy Causey, Superintendent of the

††† Florida Keys National Marine Sanctuary (FKNMS), and

††† Sanctuary Rangers (Florida Department of Natural Resources,

††† Bureau of Environmental Land Management) are thanked for

††† their cooperation during the field survey. Personnel from the

††† USGS in St. Petersburg, Fla., and the National Oceanic and

††† Atmospheric Administrationís (NOAA) FKNMS conducted

††† most of the project in the middle and upper Keys as a

††† cooperative study under permit FKNMS-29-97. We thank

††† Captain Stephen R. Cawthon who led Captain's Lady on her

††† final voyage as a research vessel in 1997, for assistance in data

††† collection. Appreciation is extended to numerous colleagues for

††† their field assistance. All are acknowledged by name in publications

††† resulting from each part of the project. Stanley D. Locker, University

††† of South Florida St. Petersburg campus, assisted in numerical data

conversion to compensate for the rapid speed-of-sound return in

shallow water. James G. Flocks, USGS geologist, produced the

seismic-profile trackline navigation and data map panels for

contouring. Digital cartographer Lance E. Thornton digitized final

contours into the ARC/INFO GIS program for the bedrock and

isopach plates. Jeff Dismukes provided scripts for editing and

reformattingthe navigation data for use with ESRIís ArcView 3.2.

The authors greatly appreciate the efforts of these colleagues.

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. After visual inspection of the JPG images

††††† provided in this report these notes must be made about the data.

††††† Important Notes:

††††† 1.Seismic Profiles key9717b, key9717c, key9717d, key9718a,

†† ††††††key9718b, key9723a and key9728a contain deep water delays

††††† †††ranging from 10 ms to 40 ms.

†††† 2.Also small 0.5 ms to 2 ms static shifts are seen in all profiles.

†††† ††††These shifts vary for each profile and last for short irregular

†††† ††††periods of time.

††† 3.Only 70 ms of data was collected for trackline key9717c; all

†††† ††††other lines were collected with 100 ms of data saved.

††† 4.Trackline key9716t contains no usable data; it was a test line.

Logical_Consistency_Report: This data set is from a single cruise with

††† consistant instrument calibrations.

Completeness_Report:

††† These data are collected along tracklines (2D).

††† Therefore, data are inherently incomplete. Geologic details between

††† lines must be inferred. All tracklines were recorded to 100ms.

Positional_Accuracy:

†† Horizontal_Positional_Accuracy:

††††† Horizontal_Positional_Accuracy_Report:

††††††† The position accuracy was determined with the Rockwell

†††††††† PLGR P-code GPS receiver fed to the acquistion software,

†††††††† FUGAWI V2.08. The accuracy of this receiver is within

†††††††† 100 m.

††† Vertical_Positional_Accuracy:

††††† Vertical_Positional_Accuracy_Report:

††††††† The vertical position was local sea level and there have been no

††††††† corrections to a vertical datum or for tidal variations.

Lineage:

††† Process_Step:

††††† Process_Description: Boomer processing:

††††††† Raw SEG-Y data was processed with SU and (Triton Elics

††††††† Software) to produce the JPG 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 25ms/in and 300shots/in for all tracklines.

††††††† 4)Convert Postscripts to GIF format, then to JPG format.

††††† Process_Date: 2001

††† Process_Step:

††††† Process_Description: Positional (navigation) data:

††††††† As the seismic reflection data were acquired, the position of the

††††††† vessel was continuously determined with the P-Code Global

††††††† Positioning System (GPS). Positions were recorded approximately

††††††† every second, and written to the SEG-Y header. The ASCII 500

††††††† shotpoint navigation files were extracted from the SEG-Y headers

††††††† using SU scripts.

††††† Process_Date: 2001

††† Process_Step:

††††† Process_Description: Editing navigation:

††††††† The raw navigation files were extracted from Delph

††††††† Seismic V2.10, and then run through a filter to edit out the

††††††† spurious fixes. The filtered data was also reformatted for

††††††† use with ESRI's GIS software ArcView 3.2. The edited

††††††† navigation files also had year and Julian day manually entered

††††††† to each file.

††††† Process_Date: 2001

††† Process_Step:

††††† Process_Description: Open File preparation:

††††††† No processing has been done to the SEG-Y data files provided

††††††† on this DVD. 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. Then converted to JPG with Image Magick.

††† ††††Only the JPG images are presented here.

††††† Process_Date: 2001

Spatial_Data_Organization_Information:

Indirect_Spatial_Reference:

††† Horizontal X and Y locations (latitude and longitude) for each shot

††† location are provided in ASCII position files, along with the time the

††† shot was recorded in Greenwich Mean Time (GMT).

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 the smallest being 14 MB to the largest being 142 MB.

††† 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:

††††† <http://www.seg.org/publications/tech-stand/index_body.html>

††† Entity_and_Attribute_Overview:

††††† Graphic image file:

††††† Each profile is available as a GIF or JPG image. The trackline maps

††††† provided are GIF images that contain hot-links to the seismic profile

††††† JPG images. The profiles range in size from 1.1 MB to 8.9 MB.

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 on-line only by special

††††††† arrangement with the distributor above.

Resource_Description: U.S. Geological Survey Open-File Report 02-XXX DVD

Distribution_Liability:

††† This Digital Versatile Disc (DVD) 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 stateor reflect those of the United

††† States Government or any agency thereof.

 

††† Although all data published on this DVD have been used bythe 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 ASCII 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.

††††††† File_Decompression_Technique: none

††††††† Transfer_Size:

††††† Digital_Transfer_Option:

††††††† Offline_Option:

††††††††† Offline_Media: DVD

††††††††† Recording_Format: UDF (Universal Disc Format)

††††††††† Compatibility_Information: UNIX, LINUX, DOS, MAC

††† Fees: available from the Denver Open-File Sales department, prices vary.

††† Ordering_Instructions: Most open-file reports are available from USGS

†††††† Information Services, Box 25286, Federal Center, Denver, CO 80225

†††††† (telephone: 303-202-4210; email: infoservices@usgs.gov)

Technical_Prerequisites:

††† Use of SEG-Y data requires specialized seismic processing

††† software, such as Unix or Linux based public domain

††† software Seismic Unix (SU) developed by the Colorado School

††† of Mines, Center for Wave Phenomena, which can be downloaded

††† from <http://www.cwp.mines.edu/cwpcodes> free of charge.

Metadata_Reference_Information:

Metadata_Date: 20010410

Metadata_Contact:

††† Contact_Information:

††††† Contact_Person_Primary:

††††††† Contact_Person: Gina M. Peery

††††††† 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: gpeery@usgs.gov

Metadata_Standard_Name: Content Standard for Digital Geospatial Metadata

Metadata_Standard_Version: FGDC-STD-001-1998


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