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USGS · 70014293

Sandstone porosity as a function of thermal maturity

J. W. Schmoker·D. L. Gautier
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Abstract

Sandstone porosity decreases in the subsurface as a power function of thermal maturity: ϕ = A( M ) B , where ϕ is porosity and M is a measure of thermal maturity representing integrated time-temperature history; A and B are constants for a given sandstone of homogeneous properties but vary between data sets. The commonly observed exponential dependence of sandstone porosity upon depth follows as a special case from this power-function relation when temperature increases linearly with depth. The consideration of sandstone porosity in terms of time-temperature exposure offers advantages in the comparison of porosity data from diverse geologic settings, the recognition of unusual porosity within a sandstone sequence, and the prediction of porosity ahead of the drill and at times in the geologic past.

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J. W. Schmoker, D. L. Gautier. 1988. Sandstone porosity as a function of thermal maturity. https://doi.org/10.1130/0091-7613(1988)016%3C1007%3Aspaafo%3E2.3.co%3B2

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