Factors Influencing Elastic Properties on Carbonate Rocks, Lessons Learnt from Two Case Studies and from Simulation Results

Abstract

In order to understand the large scattering of elastic properties of carbonate rocks, two datasets were chosen in two different geological formations (non-tropical carbonate from Australia and actual continental carbonate from Turkey). Three statistical methods that aim to quantify the influence of Geological depositional environment and dominant pore type, that highlight similarities and differences on petro-elastic and petrophysic behaviors. Geological depositional environment information would be main reason for Vp variation as shown by Study 1, while in study 2 pore-type could have a strong link with P-wave velocity. To understand the origin of those similarities and differences, and to identify common information hidden inside the geological meanings, several simulation tests have been performed by digital rocks, in order to quantify the influences of the pore volume fraction, pore size and pore shape of carbonate microstructure. The numerical simulation shows that the pores size has statistically no influence on the elastic response; the pore shape is one of the main impacting parameter of the elastic properties. The future work consists on the understanding of influence factor for petrophysic parameter by more simulation results. The ultimate objective of this study is to identify factors that influence seismic velocity and then use it to better interpret the petrophysic parameters from seismic inversion.