Analysis of heterogeneous sandstone reservoirs is one of the most difficult problems. These reservoirsusually produce from multiple layers with different permeability and complex formation, which is oftenenhanced by natural fracturing. Therefore, using new well logging techniques like NMR or acombination of NMR and conventional open hole logs, as well as developing new interpretationmethodologies are essential for improved reservoir characterization. Nuclear magnetic resonance(NMR) logs differ from conventional neutron, density, sonic and resistivity logs because the NMRmeasurements provide mainly lithology independent detailed porosity and offer a good evaluation of thehydrocarbon potential. Integration of NMR logs, other open hole logs and SCAL minimizes uncertaintiesin the determination of formation porosity, permeability and capillary pressure curve.This paper focuses on determination of three petrophysical parameters of heterogeneous gas sandreservoirs; 1) Determination of DMR porosity, Φ_(DMR), it is deduced from NMR porosity and densityporosity, 2) NMR permeability, KBGMR, it is based on the dynamic concept of gas movement and bulkgas volume in the invaded zone and 3) Capillary pressure, it is derived from relaxation time T2distribution.
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