Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

This Article Figures Only Full Text Full Text (PDF) Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Thomas, J. W. Articles by Neff, W. H. Search for Related Content GeoRef GeoRef Citation

Teepee technology applied to seismic acquisition P-wave design, Part 3

3D ocean-bottom-cable example

Dawson Geophysical, Midland, Texas, U.S.

John M. Hufford, Gary M. Hoover and Warren H. Neff

Bartlesville, Oklahoma, U.S.

Corresponding author: JohnHufford@cableone.net

The first 20% of the full text of this article appears below.

This is the concluding installment of a three-part series that introduces and demonstrates an innovative concept for seismic acquisition design. The first article introduced the concept of teepees for visualizing subsurface coverage. The second illustrated the step-by-step application to design a 3D land-based seismic acquisition. In this article, the teepee concept is applied to an ocean-bottom seismic acquisition design.

There is no difference in the design philosophy of a typical 3D land and an OBC survey using teepee technology. The six-step design process is followed in both applications: (1) determine the proper teepee size and shape; (2) ascertain the associated surface configuration or "apparent spread" assuming unlimited recording equipment; (3) determine the teepee overlap or multiplicity in each dimension; (4) calculate the number of apparent spread configurations required in each dimension to properly image the subsurface area; (5) optimize the surface configuration, based on source and/or equipment limitations, to minimize the project cost; and (6) integrate the optimized surface configuration into the final acquisition design. The difference in the land and the OBC design process comes primarily in the implementation of the steps, which involve the proper blend of source and receivers for economic viability. The part of the process with the flexibility to blend the sources and receivers is in the dimension of fold and equipment limitation (steps 3 and 5).

This OBC survey design example is to be acquired with the same constraints as the survey in the previous land example. The geometry type is to be full source-to-receiver azimuth with offset, normally labeled "true" 3D. This yields a length-to-width ratio for the teepee dimensions of approximately one. The bin size is 25 m in both dimensions, which determines the surface source/receiver trace densities to be 50 m. The required fold is 48 and the maximum source-to-receiver offset . . . [Full Text of this Article]