Abstract
Neutron/density measurements have been used to derive formation porosity. While this yields acceptable results in clean liquid-filled lithologies (sands), the effects of lithology, hydrocarbon fill (gas), and formation heterogeneity in shaly sands increases the uncertainty in computed porosities. The technique of using combined NMR relaxation times and bulk density data described in this paper significantly reduces uncertainty in derived logging parameters through elimination of the neutron log. This removes the need to correct for flushed zone
This paper describes the application of DMR technique in cored wells in a gas field, Western Desert, Egypt and it discusses the results obtained, limitations and benefits, along with the data acquisition requirements. Field examples demonstrate the importance of the (DMR) technique in place of the use of NMR or conventional logs separately in determining formation porosity and gas saturation in tight gas sand reservoirs.
