New seismic source helps in sub-basalt imaging

World Oil, March, 2002 by Helmut Jakubowicz

CONCLUSION

The BLAST results are very promising and represent a significant advance in data acquisition for basalt-covered areas, such as those found in the Atlantic Margin. However, this approach may also be useful in other parts of the world, including regions with quite different geological settings. There is a good chance that the industry will see increasing interest in seismic acquisition with very low-frequency sources of this type.

Meanwhile, Professor Ziolkowski is continuing to work on exploiting low-frequency information, and is developing his ideas in a joint research project with the British Geological Survey, Texaco Britain and Veritas. In addition, Veritas is trying to make an even better low-frequency source, which, if everything proceeds according to plan, will be available for further surveys by mid-2002.

LITERATURE CITED

(1.) Ziolkowski A., P. Hanssen, R. Gatliff, X Y. Li, and H. Jakabowice, "The use of low frequencies for sub-basalt imaging," SEG 7lst Annual Mtg. Abstracts, San Antonio, Texas, Sept. 9-14,2001.

(2.) Ebrom, D., Tatham, R., Sekharan, K. K., McDonald, 3. and Gardner, 0. H. E, "Dispersion and anisotropy in laminated versus fractured media: An experimental comparison," SEG 60th Annual Mtg. Abstracts, pp.1416--1419, 1990.

(3.) Liu, E., J. A Hudson and T. Pointer, Equivalent medium representation of fractured rocks," Journal of Geophysical Research, Vol. 105, pp. 298 1-3000,2000.

(4.) Gatliff, R. W., K. Hitchen, J. D. Ritchie and D. K. Smythe, "Internal. structure of the Erlend Tertiary volcanic complex, north of Shetland, reveled by seismic reflection," Journal of the Geological Society. Vol. 141, pp. 555-562, 1984.

Dr. Helmut Jakubowicz is Manager of External Research at Veritas DGC.