The Estimation of Heterogeneous Reservoir Productivity Based on Well Log Data

One of key parameters measured for productivity estimation at well cross-sections is the electrical resistance of rocks. This parameter varies within a wide range. One of the factors influencing on a value of electrical resistance is the mineralization of formation water which saturated rock. According to borehole observations of terrigenous rocks by geophysical logging data in the areas located at the Lower Kura and Absheron hydrocarbon-bearing regions, allows delineation of reservoirs characterized with different values of electrical resistance. Stated above factors are complicated well logging data. Processing, detection and productivity estimation of heterogeneous sand and clay reservoirs require special handling at such problem. Accounting of stratified shaliness is one of handling in such problem solving. Processing of laterologging data shows that the sounding curves against water-bearing reservoirs have a form of three-layer curve with higher penetration. Existence of the deep penetration at separated thin-bedding reservoir is possible to find by the comparison of maximum values of equivalent resistivity measured with sondes of various size. If the results are similar for all kind of sondes, then obvious that the increasing of apparent resistivity is caused by influence of anisotropy effects.