Abstract

Fractured carbonated reservoir is one type of unconventional reservoirs which has low permeability rather than conventional reservoirs in terms of complex depositional and diagenetic environment. In most of the fractured carbonated reservoirs, fluid flow characteristics such as permeability and porosity are generally difficult to estimate and the most porous intervals are not always the best reservoirs as the intervals of equivalent porosity. Permeability plays the substantial role in moving the fluid flow from the fractures of the reservoir to the wellbore. Due to the fact that, calculating the appropriate amount of permeability was seriously doubted and there were numerous challenges for petroleum engineers to obtain the accurate quantity. Estimation of permeability using regular methods such as core analysis and well testing methods are outrageously expensive and time consuming. Furthermore, a simple correlation between permeability and porosity cannot be developed. Therefore, the prediction of permeability in heterogeneous carbonates by production logging tools is a preferable methodology to reduce the squander sums of money and time in measuring the fluid properties of a carbonate reservoir such as permeability, measuring the well fluid profile, detection of mechanical problems and evaluation of well completion procedures. That is to say that, production logging tools is performed as a powerful and applicable instrument to estimate the flow rate, water-oil contact, and other fluid properties.

Key words: Unconventional reservoirs, permeability estimation, production logging tools, fluid properties.