Refining Sequence Stratigraphic Interpretations Using Benthic Fossil Communities from the Permian Basin of West Texas Thomas D. Olszewski, Department of Geology and Geophysics, Texas A&M University The aim of this project was to use ecological theory to enhance sequence stratigraphic interpretation. Using brachiopod assemblages from the Permian Basin of west Texas, we found that ecological systems can accommodate relatively small environmental changes associated with depositional sequence boundaries without disruption of their community structure, whereas larger environmental changes associated with higher order boundaries led to reorganization of membership, abundances, and landscape distribution of ecological communities. Bell Canyon Fm. In this case, paleoecological analysis indicates that the base level change associated with the Pinery-Rader boundary was of lesser magnitude than the event between the Rader and Lamar, a matter which had not been resolved based on previous sedimentological and stratigraphic work. Constraining the magnitude of sequence bounding surfaces places an important constraint on correlations, thereby providing greater understanding of the stratigraphic architecture of the Permian Basin, one of the largest domestic hydrocarbon provinces in North America.