. Most quantitative log analysis is aimed at determining shale content, porosity, and water saturation. These terms define the oil or gas in-place in the reservoir at initial conditions. What we really like to know is: are the wells good, that is, will they produce anything? How many wells are productive in the investigated area? And what will the wells produce oil, gas or water? To know this, we must determine values for permeability and net pay parameters for the studied wells.
The wireline log analyses for eight wells in the study area have been used to evaluate the petrophysical parameters of the Middle Miocene Kareem Formation. These parameters include the effective porosity (e), water saturation (Sw), movable hydrocarbon saturation (Shm), residual hydrocarbon saturation (Shr), bulk volume water (BVW), movable hydrocarbon pore volume (MHPV) and lithologic content in terms of volume of shale (Vsh) and matrix volume (Vs.s and Vcarb.). Moreover, the effective permeability was calculated.
To illustrate the horizontal distribution of the different petrophysical parameters, a number of isoparametric maps were drawn. The relationships between the net pay parameters were analyzed through the construction of four crossplots to evaluate the Kareem Formation characteristics. The application of the different log analysis methods and net pay parameters largely improved our knowledge and discriminated accurately between zones that are capable of commercial oil production and those that are not, and water productive or tight zones.
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