Waveland Field, Unique Structural and Stratigraphic Trap: ABSTRACT

Abstract

Waveland field, located in Hancock County, Mississippi, and currently being developed, was discovered in 1965 by Humble Oil and Refining Co. Gas Unit 1, Sec. 22, T8S, R15W. One additional field well was drilled, a northwest diagonal in Sec. 16, T8S, R15W. After these two field wells were completed and put on production, there was no additional development until 1975, when lease blocks were assembled by Phillips Petroleum Co., Saga Petroleum, Marshall R. Young Oil Co., and others. There is no massive deposition of Ferry Lake Anhydrite in the area. Because of the lack of massive anhydrite, actual definition of the formations of the Trinity Group (Lower Cretaceous) is difficult to impossible. However, it is interpreted that the primary reservoir of Waveland, a porous limestone, is the Mooringsport Formation. The depositional environment of the Mooringsport limestone reservoir is extremely complex because of the influence of the large regional carbonate banks on the south. For convenience, the Mooringsport porosity zones are lettered A through G. To date, the A and B zones are the primary contributors to production. The B zone may be subdivided within the field proper. The reservoir rock is best described as a two-porosity system--matrix porosity (range 6 to 12%) and vugular porosity (range 7 to 16%) directly related to the mineralogy, lithology, and diagenetic history. Matrix permeability is generally low, not exceeding 2 md and usually less than 1 md. Fractures are essential for good productivity and intense fracturing is present in all the higher crestal positions. The Waveland field comprises the crestal 19,000 productive acres (7,600 ha.) of a north-to-south-elongated nose having no apparent structural closure, fault closure, or north dip at the Mooringsport limestone level. Structural elevation at the Mooringsport level is a major factor in determining hydrocarbon saturation, but no direct relation has been found among pore-throat size, rock type, porosity, structural elevation, and hydrocarbon saturation. The Waveland field is a complex combined structural and stratigraphic trap. End_of_Article - Last_Page 1428------------