Recently, deep and ultra-deep shales (depth >3500 m) of the Lower Paleozoic Wufeng–Longmaxi formations (WF–LMX) have become attractive targets for shale gas exploration development in China, their contents may be influenced by occurrence water to some extent. However, content its distribution different nanopores rarely been reported. In this study, a suite WF–LMX samples (5910–5965 m depth) ...

Although there is no assumption of pore geometry in derivation of Gassmann’s equation, the pore geometry is in close relation with hygroscopic water content and pore fluid communication between the micropores and the macropores. The hygroscopic water content in common reservoir rocks is small, and its effect on elastic properties is ignored in the Gassmann theory. However, the volume of hygrosc...

the simultaneous flow of oil and water in porous media is described by relative permeability curves, mainly derived from laboratory experiments. relative permeability is of paramount importance in predicting reservoir production performance and drive mechanisms and its value depends largely on the volume fraction of fluids present in the test samples. nowadays x-ray scanners are one of the most...

let $r$ be a commutative ring. the purpose of this article is to introduce a new class of ideals of r called weakly irreducible ideals. this class could be a generalization of the families quasi-primary ideals and strongly irreducible ideals. the relationships between the notions primary, quasi-primary, weakly irreducible, strongly irreducible and irreducible ideals, in different rings, has bee...

Abstract Low salinity water flooding (LSWF) is a promising strategy for improving oil recovery in sandstone reservoirs, and recent studies have shown that the with low injection function of not only ionic composition but also pH injected brine, temperature, combined effect both on wetting properties clay mineral surfaces. Following brine flooding, initial wettability rock surfaces existed when ...

cementation factor is a critical parameter, which affects water saturation calculation. in carbonate rocks, due to the sensitivity of this parameter to pore type, water saturation estimation has associated with high inaccuracy. hence developing a reliable mathematical strategy to determine these properties accurately is of crucial importance. to this end, genetic algorithm pattern search is emp...

A nuclear magnetic resonance (NMR) logging tool can provide important rock and fluid properties that are necessary for a reliable reservoir evaluation. Pore size distribution based on T2 relaxation time resulting permeability among those parameters cannot be provided by conventional tools. For wells drilled before the 1990s many recent there is no NMR data available due to availability cost, re...

The pore-throat radius of the shale oil reservoir is extremely small, and it difficult to accurately obtain absolute permeability oil–water two-phase relative actual through conventional core experiments. However, these parameters are very important for numerical simulation. In this paper, a method characterizing flow based on pore network model that considers differential pressure diffusion pr...