ABSTRACT

Reservoir properties and production performance, integrated into a firm sequence stratigraphic framework have been assumed to be controlled by their position in this framework and the systems tract that they are representing. This hypothesis has been tested in a data set from two mature oil and gas fields, located 10 miles offshore Louisiana. Supported by digital well log data, 3-D seismic, sidewall core data and a complete production information package, the systems tracts of fourth-order sequences were scrutinized. The Miocene work section encompasses 58 fourth-order and 10 third-order sequences.

As a result of this research the three systems tracts of this framework-lowstand (LST), transgressive (TST), and highstand (HST)--show different but characteristic trends in porosity, permeability, and production rates, which in turn can be used to predict potential hydrocarbon production performance. The LST's of this data set are dominated by the highest average porosity and permeability values, followed by HST's and TST's. The production rates of the HST's are highest, followed by LST's and then TST's. A comparison of the rock or production properties of the subunits of fourth-order sequences with third order shows that the latter have different trends, which are not similar to the characteristics of fourth-order systems tracts.

The final product of this research is a database that allows the user to search with different criteria, supported by applying various query setups. This database includes the rock properties, the production output, and facies description for every systems tract that has produced hydrocarbons.