ABSTRACT: The Prudhoe Bay Well Planning System, an Application Used to Evaluate Potential Well Locations

Pamela J. Barnes

Development planning at Prudhoe Bay, the largest oil field in North America, requires the synthesis of extensive geological, geophysical, and petrophysical data to optimally locate new wells. At BP Exploration (Alaska), Inc., this effort is aided by the Prudhoe Bay Well Planning System, a software application that uses a numerical description of the Ivishak reservoir to predict geologic information at planned well locations and estimate hydrocarbon in place volumes associated with well targets.

The Well Planning System is linked to a three-dimensional model of the Ivishak reservoir and contains structural, stratigraphic, rock property, and fluid contact data. The software interrogates the model at a planned well location and, using instructions from the geologist, processes the raw data into well forecast reports. Geologists also use the system to build polygons representing the anticipated drainage area of a well target, using well locations or fault coordinates to identify polygon vertices. These polygons areally bound an integration through the model as original and current oil and gas volumes are calculated. Fluid contacts can be modified prior to integration to reflect fluid movement in the reservoir and refine current oil estimates.

Implementation of the Well Planning System has benefited Prudhoe Bay development well planning in several ways. Proposed well evaluations are accomplished efficiently and, because geologists are able to rapidly evaluate alternate locations, individual well targets can be optimized. In addition, geologists' time is now spent on the evaluation of rather than collection of data, contributing to improved well forecasting results.

AAPG Search and Discovery Article #91003©1990 AAPG Annual Convention, San Francisco, California, June 3-6, 1990