| This study performs a petrophysical analysis and rock-physics modeling of the Traverse Formation, using eleven different wells. In the first part of this study, well logs, crossplots, and mineral identification were used to determine the rock components, lithology, and to predict the sonic velocities of carbonate rocks using conventional methods for two of those wells.;In the second part of this study, rock-physics modeling methods were used to predict the sonic velocities using the Kuster-Toksoz equations. Sonic velocities are very difficult to predict in carbonate rock because of their complex pore systems. To overcome this difficulty, multiple aspect ratios for porosity were used to calculate sonic velocities for the limestone, dolomite, quartz, anhydrite, and shale mixtures. Having determined the lithology from conventional log analysis, the matrix moduli and densities were estimated. Then the Kuster-Toksoz equations were used to calculate the elastic properties, using different aspect ratios in an effort to obtain the best estimate for the observed P-wave velocities, and to predict S-wave velocities (which had not been recorded), and compare them with the predicted S-wave from Greenberg and Castagna equations. |
