Integrating seismic geomorphology into improved reservoir models of shelf margin deltas, Corallita/Lantana Field, Trinidad
MetadataShow full item record
This project analyzes the reservoir architecture and compartmentalization of the as yet undeveloped Corallita and Lantana gas fields. Corallita-Lantana, discovered by Amoco Production Company in 1995, is an undeveloped dry gas discovery in the Greater Mahogany region offshore in the eastern shelf of the Columbus Basin, offshore S.E. Trinidad (Wood, 2004). It is currently estimated to contain 1.5 TCF of gas resource in Pleistocene age reservoirs. Several factors complicate development of the Corallita-Lantana field, including fault seal, trap definition and reservoir compartmentalization. 1120 km2 of 3D seismic combined with well log analysis have been used to explain the reservoir shape, size and distribution. Seismic coherency, amplitude analysis and spectral decomposition have been integrated to improve understanding of reservoir heterogeneity and compartmentalization, and spatial changes in reservoir petrophysics. Such knowledge will enable engineers to establish the best production design, and implement the most economical artificial drive mechanism for production. I made statistically robust, geomophometric analysis of the reservoir by assigning binary codes to various facies and incorporating well log character using cumulate analysis software on interactive computer workstations. The reservoir of interest (TQ60) shows varying seismic facies architecture from shelf to slope. The seven seismic facies identified are conformable topset facies, interchannel facies, canyon facies (mass transport deposits), channel levee systems, ponded turbidities, conformable horizontal slope facies and faults which are identified on seismic attributes extractions. Assigning digitized codes to different facies is a fast and effective way to model a reservoir and compare different data sets. The result of combining geomorphology from seismic attributes to reexamine the stratigraphic framework is a predictive tool that strengthens any model from sediment content, basin plays characterization, risking prospects and well placement models. Development of the field is now being planned and approximately 56% of the reserves are in the Pleistocene age TQ60 sand across both the Lantana and Corallita fault segments. Results from this study do not only apply to the development of the field, but explain how reservoir shape and distribution can be addressed in all shallow marine and fluvial-deltaic environments.