Accurate identification of the spatial distribution of various pore types in carbonate reservoirs by seismic inversion is challenging due to the diverse pore structures resulting from deposition and diagenetic modification and low-resolution of seismic data. We use a bulk-frame flexibility factor from a rock-physics model as an indicator to analyze the effect of pore structure variations on acoustic velocity and impedance. A good correlation is found between acoustic impedance (AI) and the product of porosity and Î³ representing different pore types. It is found that when <4.5, the dominant pore type is moldic with relatively high AI value; when 5.5<<15, intercrystalline pores are prevalent and the AI is lower than moldic pores in a given porosity range. Model-based post-stack inversion built by strata models and seismic data with entirely different resolution are then applied to estimate the spatial variation of carbonate pore shapes. Inversion results based on high-resolution strata model and high-resolution seismic data have the highest resolution and could help delineate diversified pore structures precisely. The resolution of seismic data is the most significant factor for the final resolution of model-based inversion. These methods can be applied to estimate the spatial variation of carbonate reservoir pore types more accurately.
Presentation Date: Wednesday, September 18, 2019
Session Start Time: 9:20 AM
Presentation Time: 10:35 AM
Location: Poster Station 3
Presentation Type: Poster