ABSTRACT

Prospective evaluation of “XY” field in southwestern offshore Niger Delta was carried out with a view to delineate the structural and stratigraphic traps present in the study area. The research methodology involved horizon and fault mapping to produce subsurface structural maps. Attributes used to analyze the field under study includes: Variance time slice which was used to illuminates the main fault structure on the field and aid as guide to proper mapping. Similarly, this was used to delineate the orientation of the fault across the field while Wireline log signatures were employed to identify hydrocarbon bearing sands. The data set used consists of Petrel simulation software 2013, general well data, well heads, well logs, well tops, checkshot, 3-D Siesmic in SEGY format. Three (3) hydrocarbon bearing reservoirs were identified and they fall within the Agbada Formation (Reservoir 1, 2, and 3), with gross thickness ranging from 50ft to 123ft. Besides, due to the fact that the sands aren‟t entirely clean the three reservoirs have a net thickness ranging from 40ft to 100ft. Three (3) major faults were mapped on the seismic inlines, two were major faults while the last one was a minor fault. After mapping the faults, horizons were picked along the seismic inlines and xlines and a two way time graph was plotted to generate a linear function. The amplitude attribute overlay time slice generated conform to structure which indicate accumulation of hydrocarbon. The high amplitude zone also doubled as the boundary of the hydrocarbon reservoirs (fluid contact) as they also conform to structure. The prospect can be chosen from any portion of the high amplitude zone recognized in the study.