First Break - Volume 28, Issue 7, 2010

In one of his occasional contributions on the philosophy of science, Paolo Dell’Aversana discusses the processes involved in integration and how they offer the potential for innovation.

Mark Farabee, Margaret Trenholm, and Rich Dodds of Halliburton argue that when considering how asset teams can leverage all the information they possess to make better decisions and improve production and recovery rates, they need a solution that allows stimulation data to be integrated with G&G data to understand how the reservoir will fracture and respond to stimulation treatment.

Jakob B.U. Haldorsen, Fuping Zhu, Nobuyasu Hirabyashi, William H. Borland, Hari Kurniawan, Hiroaki Yamamoto, Khalid Al-Ghammari and Richard T. Coates make the case for use of borehole sonic data to increase understanding of a producing reservoir.

Tone Kråkenes presents some examples of how software developments are improving the quality of 3D models to help reservoir management decision making.

Ernst D. (Paul) Rode, Hatem Nasr and Monzer Makhous introduce their work on the possibilities of passive seismic, particularly infrasonic passive differential spectroscopy, as a supporting technology for reflection seismic and other methods. A separate article follows with a case study of the techniques used in India.

E.D. Rode, S.R. Das, S. Ravindran, M.K. Mukherjee, A. Bordoloi and P. Jinagam show with an Indian case study how application of infrasonic passive differential spectrascopy technology for marginal fields and by-passed oil in brown fields is significant in eliminating the risk of drilling dry holes.

Sherilyn Williams-Stroud, Jo Ellen Kilpatrick, Brian Cornette, Leo Eisner and Morris Hall present a case study to illustrate how microseismic events recorded from hydraulic fracture stimulations compare favourably with a separate formation micro-imaging log in the treatment well, and can provide data on fracture characterization away from the borehole.

In this paper, I argue that when there are significant overburden time shifts in time lapse-seismic surveys, the time shifts experienced by multiples can exceed those experienced by the surrounding primaries. Such misaligned multiples will lead to an overestimate of true time shifts for the primaries, especially in areas where multiple energy is strong compared to primary energy. This mechanism explains why large time shifts are observed in the underburden, and is supported by both model computations and real observations from the Tyra Field.

A seismic attribute is any measure that helps to better visualize or quantify features of interest in seismic data. Several refraction attributes, in addition to seismic velocity, can be readily computed from the first arrivals in seismic data. Refraction attributes can be usefully employed in the geotechnical characterization of the near surface. The major effect of tomography is largely cosmetic because it rarely improves resolution. Numerous refraction tomograms, which range from the geologically improbable to the very detailed, can satisfy the travel time data to sufficient accuracy. In the initial or reconnaissance stage, refraction attributes can be used to compute detailed starting models and to resolve non-uniqueness inherent in refraction tomography. Whereas refraction tomography non-uniquely models the single attribute of seismic velocity, this study demonstrates that the additional model parameters of scaled density ratio and P-wave modulus strength can be readily computed from combinations of refraction attributes. The spatially extensive refraction attributes can then be integrated with quantitative borehole and other geotechnical data using multivariate geostatistics. It is concluded that more useful quantitative geotechnical models of the near surface can be obtained by employing a wider range of attributes than the seismic velocity alone.