Comparison of three field parameters from a 3C-2D test line, Conroe, Texas
Han-xing Lu, Kevin W. Hall, Robert R. Stewart, Robert E. Lory
In August of 2003, a 2D seismic test survey was conducted by Veritas for Exxon Mobil along a busy state highway in Conroe, Texas. Two vibrator source lines (line 501, 2 vibrators, 16 sweeps per VP; line 502, 4 vibrators, 4 sweeps per VP) were recorded by two full length receiver lines (line 101; standard 6-geophone array; line 201; Sercel DSUs), and a shorter receiver line (line 102; standard 6-geophone array, podded). In addition, a number of noise spreads were acquired, as well as a variety of tests involving explosive sources and/or different receiver deployments, for example, receiver burial at depths up to ~9 m (30 ft).
In this paper, we present comparisons of stacked sections obtained from shots correlated and vertically stacked in the field to those obtained from shots correlated using a diversity power stack at CREWES. The effects of different source arrays recorded by the same receiver array, and the effects of different receiver arrays for a common source array are also considered.
In general, data quality of the stacks with large amounts of traffic noise can be significantly improved by diversity power stacking repeated shots, especially in the deeper section. Unfiltered 6-geophone arrays provide better images than pods of 6 geophones. High CDP fold results in better images after diversity stacking than low fold.