Ukpebor Osahon¹, Maju-Oyovwikowhe Gladys Efetobore^2,

This study focuses on the reservoir characterization of the UM field in the Niger Delta using Amplitude Versus Offset (AVO) analysis. The study integrates various data sources, including 3D seismic data, well deviation survey data, and checkshot survey data, to gain a comprehensive understanding of the reservoir properties. The AVO analysis involved cross-plotting gradient against intercept values derived from the AVO analysis, revealing an anomalous deviation from the background trend. The identified Class IV AVO anomaly suggests the presence of a gas sand reservoir within the study interval. The seismic stacks and attribute slices confirm the amplitude variations at different offsets, further supporting the identification of the gas sand reservoir. The results provide valuable insights into the reservoir's seismic response, as indicated by the amplitude variations observed in the seismic stacks. Additionally, the AVO analysis allows for the assessment of lithological variations within the reservoir. The cross-plot of gradient and intercept values aids in understanding the reservoir's fluid content, as different combinations of these parameters correspond to specific lithologies and depositional environments. The findings of this study have significant implications for reservoir evaluation and exploration activities. The identification and characterization of the gas sand reservoir using AVO analysis contribute to a better understanding of the subsurface properties in the UM field. This knowledge can guide future drilling and production decisions, leading to more effective reservoir management and hydrocarbon recovery strategies.

reservoir characterization, AVO analysis, gas sand reservoir, seismic response, lithological variations, fluid content, Niger Delta