Topic
Effective porosity
About: Effective porosity is a research topic. Over the lifetime, 1199 publications have been published within this topic receiving 26511 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this paper, the effect of water saturation on rock thermal conductivity measurements using a set of 67 samples covering igneous, sedimentary and metamorphic rocks was studied using a geometric mixing law prediction model for two phase system.
42 citations
TL;DR: Investigation of bacterial transport through cores of intact, glacial-outwash aquifer sediment found easily-measurable sediment characteristics accounted for 66%, 61% and 89% of the core-to-core variability in the bacterial effective porosity, dispersivity and attachment-rate coefficient, respectively.
42 citations
TL;DR: This paper showed that porosity is preferentially preserved where oil first accumulated in these unusually homogeneous overpressured reservoir sandstones, at the top of the cliff, and the maximum porosity of the Fulmar Formation is systematically highest immediately below the top seal.
Abstract: Exceptionally high-porosity sandstones are reported from oil provinces worldwide, yet the mechanism of porosity preservation remains controversial. We present strong evidence that the exceptional porosities in the Jurassic Fulmar Formation within the North Sea are the result of early oil charging preventing cementation and chemical compaction in sands with relatively low detrital clay contents, although overpressure and grain coatings do have some effect. The most dramatic evidence that reservoir quality is related to early oil charge is the spatial distribution of the porosity: the maximum porosity of the Fulmar Formation is systematically highest immediately below the top seal, and decreases below this despite uniform sedimentology. Hence, porosity is preferentially preserved where oil first accumulated in these unusually homogeneous overpressured reservoir sandstones, at the top. Oil charge prevents or significantly retards chemical compaction and cementation of a reservoir, preserving porosity. There is independent evidence for early oil charging of reservoirs within the Central Graben, from fluid inclusion studies and K–Ar age dates of authigenic illite. Micro-quartz grain coatings, which have been proposed to preserve porosity during burial, are associated with only 5% extra porosity in sands that exceed the worldwide average sandstone porosity by almost 20%.
42 citations
TL;DR: In this paper, it is shown that diffusion through GCLs (or thin bentonite layers) can be modeled using a bulk porous media diffusion coefficient (Dp) consisting of the total porosity, nt, and a deduced diffusion coefficient, Dt, Dp = ntDt.
Abstract: The apparatus and procedure for performing tests to obtain inorganic diffusion coefficients for Geosynthetic Clay Liners (GCLs) are described, and the processes (diffusion, anion exclusion and osmosis) that can affect the interpretation of these tests are discussed. Results from several inorganic diffusion tests on GCL and bentonite specimens show that the diffusion coefficients deduced for sodium (Na+) and chloride (Cl−) are directly related to the final bentonite void ratio. It is shown that diffusion through GCLs (or thin bentonite layers) can be modeled using a bulk porous media diffusion coefficient (Dp) consisting of the total porosity, nt, and a deduced diffusion coefficient, Dt, (Dp = ntDt) without the need to establish the true effective diffusion coefficient () without the need to establish the true effective diffusion coefficient (De) and effective porosity (ne). However, for a longer bentonite plug sample it is shown that the true effective diffusion coefficient (De) and effective porosity (ne) must be established to predict the contaminant transport through the sample.
42 citations
TL;DR: In this article, effective porosity, defined as the porosity calculated using drying at a relative humidity of −70 MPa, is used in a generalized Kozeny-Carman equation to predict saturated hydraulic conductivity, Ks=bφen, where b and n are constants.
41 citations