Tebo, Juliana¹, Bruce S. Hart¹ 
(1) McGill University, Montreal, QC

ABSTRACT: 3-D Seismic Imaging of Porosity in Jurassic Carbonates: Smackover Formation, Southern Alabama

In this poster we illustrate the use of 3-D seismic attribute studies for predicting the distribution of physical properties in the subsurface. Using a data set consisting primarily of digital logs and seismic data, we show how correlations may be identified between seismic attributes and physical properties (porosity), and how those relationships may be exploited to predict the distribution of the property of interest in three dimensions. The results of these studies: a) provide quantitative, site-specific 3-D models of physical properties that are of more use for reservoir management than qualitative models derived from facies modeling or sequence stratigraphic analysis, b) are generally more geologically reasonable than geostatistical studies, c) provide sedimentary geologists with fundamental insights into depositional and/or diagenetic controls on the distribution of properties of interest, d) need to be rigorously evaluated by integrating other types of data and analyses, and e) are best thought of as supplementing, rather than replacing, conventional geologic analyses. 
Our study area is Appleton Field in southern Alabama. At this location we predict the 3-D distribution of porosity in carbonates of the Upper Jurassic Smackover Formation using a neural network and a combination of four attributes. Our results suggest that porosity was best developed, and preserved, in deep water thrombolite facies of the reef front. Knowledge gained from this study can be applied to other situations where thrombolitic facies are encountered. These include other Smackover carbonate buildups of the basement ridge play or other Upper Jurassic carbonate buildups of the northern Tethyan ocean

AAPG Search and Discovery Article #90026©2004 AAPG Annual Meeting, Dallas, Texas, April 18-21, 2004.