National Centers for Environmental Information (NCEI)

MULTICHANNEL SEISMIC REFLECTION PROFILES

Southeastern Gulf of Mexico

Data Announcement 83-MGG-14

    In 1980, a dense grid of 24- and 48-fold seismic profiles was acquired by the University of Texas Institute of Geophysics in the western Straits of Florida and southeastern Gulf of Mexico in a site survey for the Deep Sea Drilling Project (DSDP) Leg 77. The seismic source consisted of Western Geophysical Maxipulse 0.27 kg explosive charges. The University of Texas has provided these data to the National Geophysical Data Center (now the National Centers for Environmental Information)for public dissemination.

    Data were sampled every 2 ms and low-pass filtered at 124 Hz on a Texas Instruments DFS-IV Acquisition System. Onshore processing included debubbling, common-depth-point sorting, semblance velocity analyses, normal move-out corrections, stacking, bandpass filtering, automatic gain control scattering, and muting to exhibiting both reflector onlap and truncation. The erosional surface is highlighted on seismic profile SF-22, which crosses DSDP sites 540 and 97 ("Deep-sea Erosional Unconformity in the Southeastern Gulf of Mexico," D.M. Angstadt, J.A. Austin, Jr., and R.T. Buffler, Geology, vol. 11, p. 215-218, April, 1983).

DATA AVAILABLE

Multichannel Seismic Profiles (28 lines, 40 sections) available in plastic sepia, paper sepia, and blackline.

2 Shot-point Location Maps available in plastic sepia, paper sepia, and blackline.

1 Bathymetric Contour Map available in plastic sepia, paper sepia, and blackline.

Merged navigation, magnetics, and bathymetry data are available on 1 magnetic tape, 9-track, 1600 bpi, ASCII. This is also available on CD-ROM.