Schlumberger Releases Variance Cube-Its First Software Application Using OpenSpirit Data Access:

HOUSTON, March 13, 2001 - GeoQuest, an operating unit of Schlumberger Oilfield Services, announced today the release of Variance Cube* volume attribute software utilizing OpenSpirit for data access. Variance Cube is GeoQuest's first software application on the OpenSpirit platform-independent framework. Variance Cube is able to process seismic data in multiple formats, including the GeoQuest GeoFrame® project database or Landmark OpenWorks™. Variance Cube's use of OpenSpirit ensures a fast and seamless > workflow for customers with a variety of software infrastructures.

During a recent Variance Cube beta test, Norske Shell produced a processed volume more than twice as fast as with any other > tool they have available for this calculation.

Bernd Lahmeyer, subsurface portfolio team leader for Norske Shell, said, "We in Norske Shell regard OpenSpirit as a central part of our integration strategy for the future. In order to get experience with a commercial GeoQuest product based on OpenSpirit, we tested Variance Cube. We were really impressed by both the performance and the stability of this new product."

Based on a patented algorithm developed by GeoQuest, Variance Cube calculates the direct measurement of dissimilarity rather than the inferred similarity of seismic data. With Variance Cube on the desktop, structural and stratigraphic interpretation costs decrease as a result of cycle time reduction from days to hours and the ability to perform this processing in-house.

"Through our strong commitment to open systems, we are bringing productivity-enhancing applications, such as Variance Cube, to the market faster, " said Colin Hulme, vice president and general manager of Reservoir Software for GeoQuest. "E&P companies now have best-in-process software that fits seamlessly into their workflows."

About the Organizations GeoQuest, an operating unit of Schlumberger Oilfield Services, is the E&P industry leader for the supply of integrated software systems and data management solutions to assist petroleum companies in optimizing the value of their oil and gas reservoirs. Schlumberger Oilfield Services, a business segment of Schlumberger Limited [NYSE: SLB], is the leading supplier of services and technology to the international petroleum industry and operates offices, service locations, and research and development facilities around the world. Schlumberger is a global leader in technical services spanning the oil and gas, utility, semiconductor, smart card, network and Internet solutions industries. Schlumberger revenue was $9.61 billion in 2000. Schlumberger is on the Internet at http://www.slb.com.

OpenSpirit Corporation, based in Houston, specializes in building a vendor neutral, platform-independent application and integration framework that accelerates "time to market" for software vendors and improves workflow integration for oil and gas companies. Additional information on OpenSpirit is available at http://www.openspirit.com or via e-mail at info@openspirit.com.