Secondary Natural Gas Recovery: Targeted Technology Applications for Infield Reserve Growth in Fluvial Reservoirs in the Frio Formation Seeligson Field, South Texas

This report summarizes the results of a 3-year research program, including findings from a project experiment site in fluvial reservoirs within Seeligson field. These reservoirs comprise channel-fill and crevasse-splay sandstones, levee siltstones, and floodplain siltstones and mudstones. Despite Seeligson field's poorly contacted reservoir compartments, its potential for secondary gas recovery in the middle Frio Formation is lower compared to other fields in the FR-4 play. Seeligson field features well-connected fluvial sandstones that have been efficiently drained by a relatively higher number of completions. In contrast, many other fields in the play (such as Stratton and Agua Dulce) contain less intensively completed, isolated fluvial sandstones, representing uncontacted reservoir compartments. Differences in fluvial reservoir architecture and completion practices must be considered as an important aspect of any infield exploration program for fields in the FR-4 play and other gas plays.