Pseudo-Percolation Threshold Theory in Evaluation of Low-Porosity and Low-Permeability Oil Reservoir

Abstract

Lithology and physical characteristics between conventional clastic reservoirs and low-porosity and low-permeability reservoirs are very different, hence Archie formula will not be valid for the latter any more. In addition, well logging evaluation of low-porosity and low-permeability reservoir is one key problem but also the research hotspot in recent years. In this study, Pseudo-Percolation Threshold Theory (PPTT) has been introduced into reservoir evaluation. In this research, it has been proved that the aimed layer is low-porosity and low-permeability by studying the reservoir rock. In addition, Pseudo-Percolation Threshold φν has been determined by analyzing porosity and permeability of oil-bearing cores and process of geologic evolution. Finally, it has been proved that PPTT is much more reliable than Archie formula for low-porosity and low-permeability reservoir by numerical simulation and oilfield data.