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Pore-throat sizes in sandstones, tight sandstones, and shales

January 1, 2009

Pore-throat sizes in silidclastic rocks form a continuum from the submillimeter to the nanometer scale. That continuum is documented in this article using previously published data on the pore and pore-throat sizes of conventional reservoir rocks, tight-gas sandstones, and shales. For measures of central tendency (mean, mode, median), pore-throat sizes (diameters) are generally greater than 2 μm in conventional reservoir rocks, range from about 2 to 0.03 μm in tight-gas sandstones, and range from 0.1 to 0.005 μm in shales. Hydrocarbon molecules, asphaltenes, ring structures, paraffins, and methane, form another continuum, ranging from 100 Å (0.01 μm for asphaltenes to 3.8 A (0.00038 μm) for methane. The pore-throat size continuum provides a useful perspective for considering (1) the emplacement of petroleum in consolidated siliciclastics and (2) fluid flow through fine-grained source rocks now being exploited as reservoirs.

Publication Year 2009
Title Pore-throat sizes in sandstones, tight sandstones, and shales
DOI 10.1306/10240808059
Authors Philip H. Nelson
Publication Type Article
Publication Subtype Journal Article
Series Title American Association of Petroleum Geologists Bulletin
Index ID 70035885
Record Source USGS Publications Warehouse
USGS Organization Central Energy Resources Science Center