press release

PGS Reservoir Consultants awarded prospect generation contract By Unocal

The following news release was issued by Petroleum Geo-Services

HOUSTON & OSLO, Norway--May 20, 2002--Petroleum Geo-Services ASA (NYSE:PGO)(OSE:PGS) announced today its Reservoir Consultants division has signed a prospect generation consulting agreement with Union Oil Company of California (Unocal). This pilot project is the result of Unocal's continuing efforts to leverage external industry experience and resources (Unocal's EnergyOpps(TM) Web-based initiatives).

PGS Reservoir Consultants offers high-end subsurface consulting services and has extensive experience in the Gulf of Mexico, Central and South America, North and West Africa, the North Sea and other regions. In this consulting role, PGS' experienced Gulf of Mexico technical team will interpret a large 3D seismic survey in the western Gulf of Mexico. PGS will generate exploration ideas based on its in-depth knowledge of the project area and its regional Gulf of Mexico GIS database.

Reidar Michaelsen, PGS' chairman and chief executive officer, stated, "We are very pleased to see our Consulting group help expand PGS' role beyond that of a traditional seismic data provider. We are looking forward to providing Unocal with a high level of input and to helping further their Gulf of Mexico exploration program."

Petroleum Geo-Services is a technologically focused oilfield service company principally involved in two businesses: Geophysical Operations and Production Operations. PGS acquires, processes and markets 3D, time-lapse and multi-component seismic data. These data are used by oil and gas companies in the exploration for new reserves, the development of existing reservoirs, and the management of producing oil and gas fields. PGS' advanced geophysical technologies allow oil and gas companies to better characterize and monitor their reservoirs in order to enhance production and ultimate recovery of hydrocarbons. In its Production Operations business, PGS owns four floating production, storage and offloading systems ("FPSOs") and operates numerous offshore production facilities for oil and gas companies. FPSOs permit oil and gas companies to produce from offshore fields more quickly and cost-effectively. PGS operates on a worldwide basis with headquarters in Oslo, Norway, and Houston.

Updated: May 2002