ABSTRACT: Lithology Mapping from Seismic Data and Geological Texture Models

Philippe Doyen, Thomas Guidish, Marcus Nulsen

A Bayesian technique, called the Maximum A Posteriori (MAP) method, is presented for generating cross sectional lithologic models of the subsurface that (1) honor lithologic observations in wells, (2) are constrained by seismically derived impedance data, and (3) are consistent with geological information expressed in the form of lithologic texture models. The MAP lithologic modeling technique is illustrated using a high-resolution seismic profile and well data acquired over a sand/shale reservoir. The technique does not provide a unique lithologic model, but instead, is used to generate a family of alternative sand/shale models consistent with the recorded geophysical and well data and with a lithologic texture model provided by the geologist. The range of models is indi ative of the uncertainty in the seismic discrimination of lithology and can be used to assess risk in reservoir development.

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