Archive of Datasonics SIS-1000 Chirp Subbottom
Data
Collected During USGS Cruise SEAX 96004
New York Bight, 1 May - 9 June, 1996
U.S. Geological Survey Open-File Report 01-96
by Jenna C. Hill, William C. Schwab and David S. Foster
US Geological Survey, Woods Hole, MA 02543
This DVD-ROM (Digital Versatile Disc-Read Only Memory) has been produced in accordance with
the ISO 9660 DVD-ROM Standard and is therefore capable of being read on any computing
platform that has appropriate DVD-ROM driver software installed. Access to the
data and information contained on this DVD-ROM was developed using the HyperText
Markup Language (HTML) utilized by the World Wide Web (WWW) project. Development
of the DVD-ROM documentation and user interface in HTML allows a user to access
the information by using a variety of WWW information browsers (i.e. NCSA Mosaic,
Netscape) to facilitate browsing and locating information and data. To access
the information contained on this disk with a WWW client browser, open the file
'index.htm' at the top level directory of this DVD-ROM with your selected browser.
The HTML documentation is written utilizing some HTML 4.0 enhancements. The disk
should be viewable by all WWW browsers but may not properly format on some older
WWW browsers.
Also, some links to USGS collaborators and other agencies are available on this
DVD-ROM. These links are only accessible if access to the Internet is available
during browsing of the DVD-ROM.
The archived Chirp subbottom data are in standard Society of Exploration Geologists
(SEG) SEG-Y format (Barry and others, 1975) and may be downloaded
for processing with software such as Seismic
Unix or SIOSEIS. The subbottom data
were recorded on the ISIS data acquisition system in QMIPS format. Chirp subbottom
channel extracted from raw QMIPS format sonar files and converted to 16-bit Int.
SEG-Y format using the program QMIPSTOSEGY. Even though the data are in SEG-Y
format, it is not the conventional time series data (e.g. voltages or pressures),
but rather instantaneous amplitude or envelope detected and therefore all of the
amplitudes are positive (though not simply rectified). DOS and Microsoft Windows
compatible software for plotting SEG-Y files (PLOTSEIS)
and viewing SEG-Y headers (DUMPSEGY)
is located in the PLOTSEIS directory. Processed chirp profiles (GIF images) may
be viewed on this DVD-ROM with your WWW browser.
Beginning in 1995, the USGS, in cooperation with the US Army Corps of Engineers
(USACE), New York District, began a program to generate reconnaissance maps of
the sea-floor offshore of the New York-New Jersey metropolitan area, one of the
most populated coastal regions of the United States. The goal of this mapping
program is to provide a regional synthesis of the seafloor environment, including
a description of sedimentary environments, sediment texture, seafloor morphology,
and geologic history to aid in understanding impacts of anthropogenic activities,
such as ocean dumping. This mapping effort differs from previous studies of the
this area by obtaining digital, sidescan-sonar images that cover 100 percent of
the seafloor.
This investigation was motivated by the need to develop an environmentally acceptable
solution for the disposal of dredged material from the New York-New Jersey Port,
by the need to identify potential sources of sand for renourishment of the southern
shore of Long Island, and by the opportunity to develop a better understanding
of the transport and long-term fate of the contaminants by investigations of the
present distribution of materials discharged into the New York Bight over the
last 100+ years (Schwab and others, 1997). Data collected in 1996, USGS cruise
96004, augments data collected in 1995, USGS cruise 95007, with sidescan-sonar
and seismic reflection data collected within the New York Bight Apex region. This
report is an archive of the chirp seismic reflection data collected in 1996.
Directory BIN:
Subdirectory PLOTSEIS:
This directory contains the DOS programs for plotting SEG-Y files and viewing
SEG-Y headers.
Subdirectory SU: Contains the Seismic
UNIX scripts used to process and plot the chirp subbottom data and extract
shot navigation from the SEG-Y headers
Directory HTMLDOCS:
Contains the necessary HTML files and supporting graphics to allow the user access to the DVD-ROM via
any World Wide Web (WWW) browser.
Directory IMAGES:
Contains GIF and JPEG images that are used by HTML hyperlinks.
Directory MAPS:
This directory contains basemap and shot navigation
themes. The data may be displayed with ARCVIEW version 3.1 or above, or ARCEXPLORER.
You may need to copy the directories to disk and edit the .apr file in the PROJECT
subdirectory to reflect the new directory paths.
Directory NAV:
Subdirectory RAWNAV:
This directory contains raw DGPS navigation files as the data became available during the cruise.
Subdirectory SHOTNAV:
Contains the shot navigation data that were collected during the cruise using a USGS differential
GPS system.
Directory SEGY: Contains the Chirp SEG-Y format
data. These data were collected using a Datasonics SIS-1000 Chirp subbottom profiler.
The SEG-Y data were logged on a Triton-Elics ISIS acquisition
system. The SEG-Y format is documented in HTML.
Directory SEISIMAG: Contains the GIF format
files of the Chirp subbottom profiles generated with Seismic
UNIX
This Digital Versatile Disc-Read Only Memory (DVD-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 DVD-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 these data, software, or related materials.
Barry, R.M., Cavers, D.A., and Kneale, C.W., 1975, Recommended standards for digital
tape formats, Geophysics, v. 40, p. 344-352.
Zihlman, F.N., 1992a, DUMPSEGY V1.0: A program to examine the contents of SEG-Y
disk-image seismic data; U.S. Geological Survey Open File 92-590.
Zihlman, F.N., 1992b, PLOTSEGY V1.0: A DOS graphics program to display SEG-Y disk-image
seismic data; U.S. Geological Survey Open File 92-349A and 92-349B.
