ABSTRACT

The hydrocarbon productive Bassfield Field, Mississippi, is an excellent analog for Lower Cretaceous Hosston exploration and production. This field is a simple anticline overlying a deep-seated salt structure. Production is from the lower portions of two fluvial channel sandstone intervals, the Harper and Booth, within the Hosston Formation. Flow rates are not related to structural position but vary in different parts of the field due to changes in the sandstone depositional facies. The clayey sandstones have been deposited in a meandering river channel network. Three major reservoir rock types were differentiated using SEM, x-ray, and petrology. Porosity and permeability reduction was due to the presence of illite and kaolinite, primary dolomite cement, and secondary quartz cementation and pressure solution of the grains. Early hydrocarbon migration into the reservoirs has prevented further cementation. The petrological and petrophysical analysis also determined that a salt-based or oil-based drilling mud would lessen the damaging effects of migration and swelling on the borehole by the various clay types in the reservoir interval. Hydraulic fracture stimulation has proven to have had a considerable positive effect on production rates of the sandstones. By studying the electric logs and cores of this field, explorationists will have a better understanding of why production occurs and where other fields may be found.