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We introduce a new geostatistical method to incorporate seismic attribute maps into a three-dimensional (3D) reservoir model. The method explicitly honors the difference in vertical resolution between seismic and well-log data. The method, called sequential Gaussian simulation with block Kriging (SGSBK), treats the seismic map as a soft estimate of the average reservoir property. With this method, the average of the cell values in any one vertical column of grid cells is constrained by the value of the seismic map over that column. The result is a model that contains vertical variability driven by well logs and the vertical-variogram model and spatial variability driven by the seismic map and the arealvariogram model.

Weinberg 5C of Johns Hopkins Hospital is a very noisy hematological cancer unit in a relatively new building of a large medical campus. Because of the requirements for dealing with immuno-suppressed patients, options for introducing sound absorbing materials are limited. In this article, a case study of noise control in a hospital, the sound environment in the unit before treatment is described, the chosen noise control approach of adding custom-made sound absorbing panels is presented, and the impact of the noise control installation is discussed. The treatment of Weinberg 5C involved creating sound absorbing panels of 2-in.-thick fiberglass wrapped in an anti-bacterial fabric. Wallpaper paste was used to hold the fabric to the backing of the fiberglass. Installation of these panels on the ceiling and high on corridor walls had a dramatic effect. The noise on the unit (as measured by the equivalent sound pressure level) was immediately reduced by 5 dB(A) and the reverberation time dropped by a factor of over 2. Further, this drop in background noise and reverberation time understates the dramatic impact of the change. Surveys of staff and patients before and after the treatment indicated a change from viewing the unit as very noisy to a view of the unit as relatively quiet.

In early 1998, Chevron acquired one of the world's first full-field four-component ocean bottom cable (3D/4C OBC) surveys at the Alba field in the central UK North Sea. The primary objective of the survey was to use converted shear waves to provide a better image of the sandstone reservoir and shales within the reservoir. Pre-survey technical studies based on a dipole sonic log and 2D OBC seismic lines gave us confidence that converted waves (PS) could provide a better image of the reservoir relative to conventional P-wave seismic data. The secondary objective of the new survey was to map water movement in the reservoir after four years of production and water injection by comparing the new P-wave OBC data with the original 1989 streamer data. A strong original oil-water contact reflector seen throughout much of the field and pre-survey technical studies suggested that production-related saturation changes would be observable on the new P-wave OBC seismic data. The new data shows that both objectives were achieved with dramatic results - the converted-wave images provide the clearest image of the Alba reservoir sands ever seen and production effects are obvious on the new P-wave OBC data near several producing and injector wells. In addition, the converted-wave data has offered new insights into the shape of the reservoir. The previous lens-shaped interpretation based on P-wave data has been replaced with a far more complex shape that is at least in part related to post-depositional structural alteration. This new interpretation is also supported by improved reservoir images seen on far-offset P-wave sections. To date, two successful wells have been drilled based primarily on the converted-wave seismic data. Both wells prove the existence of ‘wings’ – structurally high sand at the margins of the channel that may represent re-mobilized and injected reservoir sand. Neither of these wings had been previously identified on the conventional P-wave streamer seismic data.

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