.... Effective stress (σ′) is expressed as the difference between total applied stress (σ) and pore pressure multiplied by Biot's coefficient (α). The ‘α’ for highly porous rocks is unity where applied load is counteracted equally by grain-matrix and pore-pressure. However, for tight rocks, only a fraction...

... log analysis Upstream Oil & Gas well logging Biot spwla 51 aspect ratio exponent pore aspect ratio Symposium biot-gassmann method porosity compressional mineral propagation saturation equation relation calculation coefficient Poisson saturation exponent porosity...

... be determined. Krief (1987 approaches the same rock physics model differently. In addition to elastic moduli of solids and fluids, the model incorporates shear moduli of the solids and the Biot compressibility constants. Thus, both compressional and shear velocities are available from Krief, whereas only...

... avertical stress component ( a and two horizontal components (a, and a The total vertical stress component (g,> is equal to overburden P-u= (p Biot s theory relates the ratio of compressibility of rock matrix at zero porosity to the compressibility ofthe bulk volume with porosity. Density log data...

... ABSTRACT Biot's theory is used on well-consolidated rocks (rocks that obey Wyllie's time-average equation) to examine the hydrocarbon effect on compressional fast- and slow-wave velocities and shear-wave velocities at low and high frequencies. To our knowledge, this is the first time the slow...