Online Journal for E&P Geoscientists

Hamada, Gharib ^*2; Elmahdy, Osama ¹
(1) KSU, Riyadh, Saudi Arabia. (2) Petroleum, UAE University, Abu Dhabi, United Arab Emirates.

Petrophysical properties evaluation of heterogeneous gas shaly sands reservoirs is one of the most difficult problems. These reservoirs usually produce from multiple layers with different permeability and complex formation, which is often enhanced by natural fracturing. Therefore, using new well logging techniques like NMR or a combination of NMR and conventional openhole logs, as well as developing new interpretation methodologies are essential for improved reservoir characterization. Nuclear magnetic resonance (NMR) logs differ from other conventional logs. Integration of NMR logs, density logs and core data shall minimize uncertainties in the determination of formation porosity, permeability and capillary pressure curve.

This paper concentrates on determination of three petrophysical parameters of heterogeneous gas sand reservoirs; 1) Determination of DMR porosity, ΦDMR, it is deduced from NMR porosity and density porosity, 2) NMR permeability, KBGMR, it is based on the dynamic concept of gas movement and bulk gas volume in the invaded zone and 3) Capillary pressure, it is derived from relaxation time T2 distribution.