Exploring the Impact of Oil Components on Seismic Attributes through Rock-Eval Core Analysis and Geophysical Logs

There are numerous aspects to consider in reservoir characterization throughout all stages of an oil production scenario, not least of which is the geochemical analysis of rocks and fluids. This is crucial as they can significantly impact activities like enhanced oil recovery (EOR), underground gas storage, and ۴D seismic surveys. This study aims to investigate the effects of key oil components such as resin, asphaltenes, aromatics, and saturation (SARA) on seismic parameters in an ۱۸m-thick carbonate interval. The seismic parameters include transition times (DT), shear and compression wave velocities (VP & VS), velocity ratio (VP / VS), and acoustic impedance (AI). Initially, ۴۲ core samples from the target intervals underwent Rock-Eval analysis to precisely identify the SARA components. Subsequently, petrophysical and seismic parameters were derived through well-logging operations. The geophysical log analysis revealed that the studied zone is predominantly composed of carbonate with calcite and minimal shale, containing ample oil and minimal water. Zones with resin and asphaltene compounds are characterized by high density and resistance, leading to reduced electrical resistance and increased seismic velocities and AI. Conversely, regions with saturated aromatic compounds and lower density show increased electrical resistance, decreased seismic velocities and AI, and an elevated velocity ratio.

Keywords:

Oil component , Geochemical analysis , Rock-Eval Analysis , Core and Well logging data , Seismic attributes.