National Centers for Environmental Information (NCEI)

MULTICHANNEL SEISMIC-REFLECTION DATA
Solomon Islands - South Pacific Ocean
USGS Open File Report 86-552*

Data Announcement 87-MGG-11

Approximately 3,500 km of 24-channel seismic-reflection profiles in the Solomon Islands region of the South Pacific for purchase from the National Geophysical Data Center (NGDC) (now the National Centers for Environmental Information (NCEI)). These data were collected in May and early June 1982 by the U.S. Geological Survey (USGS) Research Vessel S.P. LEE during Cruise L782SP. The profiles were collected as part of the Australia-New Zealand-United States Tripartite Agreement of 1982 in cooperation with the Ministry of Lands, Survey, and Natural Resources of the Solomon Islands. The USGS, Department of Interior has provided these data to NGDC (now NCEI) for public dissemination.

The seismic energy source consisted of a tuned array of five airguns with a total volume of 1,313 cu. in. of air compressed to approximately 1,900 psi. The recording system consisted of a 24- channel, 2400-m long streamer with a group interval of 100 m, and a GUS (Global Universal Science) model 4200 digital recording instrument. Shots were fired every 50 m with 100-m group intervals.

Navigational control for the survey was provided by a Magnavox- integrated navigation system using transit satellites and Doppler sonar. A 2-msec sampling rate was used in the field and the data were later desampled to 4 msec during the demultiplexing process. A 10-sec data length was recorded, which, combined with a deep- water delay, yielded up to 16 sec of two-way travel time. The sequence of processing of data was editing-demultiplexing, velocity analysis, CDP stacking, deconvolution-filtering, and plotting on an electrostatic plotter. The seismic lines are available on plastic, paper sepia, paper blackline, or on magnetic tape.

* "Multichannel Seismic-Reflection Data Collected in 1982 in the Solomon Islands Region of the South Pacific," by John G. Veddar, Dennis M. Mann, Terry R. Bruns, and Ray W. Silter, USGS Open File Report 86-552, U.S. Geological Survey, Menlo Park, CA 94025.

DATA AVAILABLE

1. Common-Depth-Point Seismic Data

    24-fold multichannel seismic data for 52 lines/59 sections in plastic sepia, paper sepia, or blackline.

    1 Navigation Chart in plastic sepia, paper sepia, or blackline.

    1 Shot-point navigation magnetic tape (9-track, 1600 bpi, ASCII). This is also available on CD-ROM.

2. CDP Stack Tapes

    52 Digital magnetic stacked tapes derived from velocity analysis (not deconvolved or bandpass filtered. Copies of tapes and description of tape format available.

    52 Digital magnetic demultiplexed stacked tapes.