SEISMIC FACIES ANALYSIS AND DEPOSITIONAL PROCESS INTERPRETATION OF ‘GEORGE FIELD’, OFFSHORE NIGER DELTA, NIGERIA

Seismic Facies Analysis and Depositional Process Interpretation of ‘George Field’ offshore Niger Delta was carried out with a view to determining the hydrocarbon potential of the area. Seismic facies were characterized using seismic reflection amplitude and continuity, internal reflection geometry, and the nature of the bounding surfaces. Four seismic facies types: I, II, III, and IV were identified and mapped. Seismic facies, coupled with the identification of key basinwide unconformities, were used to separate the strata into four megasequences: SQ_1, SQ_2, SQ_3 and SQ_4. The seismic facies maps of the sequences were generated.

Generally, the facies distribution for the sequences revealed that sequence SEQ_1 has low- moderate amplitude continuous reflection facies (Type III facies) and high amplitude continuous and sub parallel reflection facies (Type II facies) are the predominant facies type. In sequence SEQ_2 it could be seen to compose primarily of low-moderate amplitude continuous reflection facies (Type III facies). The sequence SEQ_3 was observed to consist of low amplitude continuous reflection facies (Type III facies), suggesting low energy turbidities the high amplitude continuous and sub parallel reflection facies (Type II facies) and low amplitude discontinuous sub parallel reflection facies (Type IV facies) suggesting possible mass movement deposit. And sequence SEQ_4 composed mainly of high amplitude continuous and parallel reflection facies (Type I facies).

The direction of sediments supply within the study area could possibly be from the west to east as interpreted by the variations in the seismic facies. Both high and low density turbidity current deposits were suggested as the dominant depositional processes in this area. The environment of sediment deposition in this area is delta plain, shelf, slope to toe of slope.