Franklin J Goulding¹, Tim R. Garfield¹, Kurt W. Rudolph¹, Gerrick N. Jensen¹, Rick T. Beaubouef²
(1) Exxon Exploration Co, Houston, TX
(2) Exxon Production Research Co, Houston, TX

Abstract: Seismic/Sequence Stratigraphy of deep-water reservoirs, 1. Seismic facies and recognition criteria ; Past experiences and new observations

Seismic facies analysis is a method developed by Exxon in the 1970s for the description and geologic interpretation of seismic reflection parameters. Seismic facies are mappable, three-dimensional groups of reflections whose parameters differ from those of adjacent facies units. Application of this method for reservoir prediction hs increased in deep marine settings due to increased exploration activity and the paucity of well control.

Through integrated studies of deep-water reservoirs in several basins, Exxon has made significant enhancements to seismic recognition criteria, mapping techniques and resulting depositional models. The dramatic increase in the use of 3D seismic has made many of the improvements possible.

Early seismic stratigraphic analysis recognized convex-upward external mounding as a characteristic of deep-water reservoirs. Our current dee-water seismic facies classification scheme builds on this earlier work and is based on reflection amplitude, continuity and external form. Major reservoir-prone reflection configurations include: High Amplitude Continuous Onlapping (HACO), High Amplitude Semi-Continuous (HASC), High and Low Amplitude Semi-Continuous mounded and "gull-wing" facies. The most reservoir-prone facies differ between basins. In the Gulf of Mexico, the most reservoir prone facies is HACO whereas in the lower Congo basin HASC seismic facies in confined channel complexes are the most reservoir prone.

New techniques to interpret and map seismic facies on 3D data are providing the greatest potential for improving our reservoir predictions in the immediate future.

AAPG Search and Discovery Article #90914©2000 AAPG Annual Convention, New Orleans, Louisiana