Well Logs and Seismic Data Analysis for Hydrocarbon Prospect in Kolo Creek, Niger Delta Nigeria

Abstract

Hydrocarbon prospect, analysis and characterization are entailed in the processes used in identifying and delineating features/structures in the subsurface that are likely to be potential hydrocarbon reservoirs. The research was done by analyzing and interpreting well logs and seismic data obtained from Kolo Creek. Well logs were used to identify the lithologies present, sand and shale using the gamma ray log, potential hydrocarbon zones were interpreted using the resistivity log. These identified zones were taken into consideration for Petrophysical evaluation in which parameters such as porosity, permeability, water, and hydrocarbon saturation were obtained as details in the four wells. The lithologies were correlated across the four wells to define the continuity of the identified pay zones. Seismic-to-well tie was done using checkshot data obtainable in only Well-2. Three payzones were identified and the fluid types being gas, oil and water. Porosity values ranges from 20% to 34%, water saturation obtained were within the range of 24% and 40%, and hydrocarbon saturation (defined as whole minus water saturation) ranged from 60% to 76%. These values showed that the hydrocarbon was present in commercial quantity hence production can take place. Three horizons were picked, six faults labelled A-F, four synthetic and two antithetic were identified across the seismic sections. The horizons were studied in detail, for time, depth and attribute studies. Time structural map was generated,and it showed anticlinal structure present at its center. Depth map generated also depicted information as revealed by the time map thus validating the presence of hydrocarbon. An extracted attribute map indicated areas of high amplitudes and bright spots area being indicative of hydrocarbon accumulation present. The volumetric results showed that Reservoir A had OOIP of 467 x 106 STB and STOOIP of 389 x 106 STB.