The Geomechanics and the Acoustic Anisotropy of Reservoir Rocks

Abstract

Knowing the mechanical properties (Young’s modulus (E)( ,Poisson’s Ratio (ν), Shear Modulus (G), Bulk modulus (K) andcompressibility which is the inverse of Bulk modulus) of the rocksinvolve in a reservoir, are critical factors for reservoircharacterization). Those properties affect a wide variety ofapplications into the petroleum industry; from drilling well planningand execution to production performance (sand production,compaction, subsidence, etc) passing through a wide variety of topicslike wellbore stability, well completions and of course reservoircharacterization. For these reasons, the knowledge of these propertiesis really valuable for people working in the petroleum industry and ofcourse working in reservoir characterization.This study was located in Berea town, Oklahoma, and it wasintended to identify the geomechanical and acoustic properties of asandstone sample. The Berea sandstone elastic properties arecharacterized using two methods: Quasi static and Dynamic. Adetailed explanation of the sample preparation and the testing Journal of Petroleum Research & StudiesE 20procedure is provided. Calculation results for both methods showedconsistent values for the Young’s modulus being around 3,000,000psi. The Poisson’s Ratio value is between 0.13 and 0.3. This study wasperformed in the PoroMechanics Institute (PMI) in the SarkeysEnergy Center at the University of Oklahoma, USA.Monitoring equipment was used to obtain all the informationnecessary for the proper characterization of the rock. The results ofthis work are a good tool that can be used in future simulations such ashydraulic fracturing treatment, reservoir fluid flow or reserveestimation.