Iraqi Geological Journal (Feb 2024)
Unlocking the Mysteries of the Mishrif Formation: Seismic Data Reinterpretation and Structural Analysis for Reservoir Performance Optimization in the Garraf Oil Field, Southern Iraq
Abstract
The seismic survey is based on the reflected wave’s inherent nature from the interface among layers, which depends on the layer's density and velocity. This is called acoustic impedance and is used to resolve the confusion associated with the stratigraphic structure of the Mishrif formations in the Garraf oil field. The seismic section of the Garraf oil field in Thi-Qar Province, south of Iraq, was analyzed and interpreted. Considering the most important petroleum accumulation reservoir in the Garraf oil field, to update the structural images of the Mishrif Formation. A seismic study of the actual amplitude reflections, temporal maps, and three-dimensional depositional models demonstrated that the Mishrif Formation generate hydrocarbon from an individual structural trap in the presence of oil. Numerous abrupt discontinuities were observed in the seismic reflectors of the reservoir units of the Mishrif Formation, suggesting either a reef or a fault. The correct probability can be shown by establishing a historical match between the reservoir model and the actual behavior of the reservoir or by running a 3D vertical seismic profile log (VSP), which is more precise than the seismic survey previously used to explore faults.