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Porosity and grain size controls on compaction band formation in Jurassic Navajo Sandstone

Richard A. Schultz·Chris H. Okubo·Haakon Fossen
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Abstract

Determining the rock properties that permit or impede the growth of compaction bands in sedimentary sequences is a critical problem of importance to studies of strain localization and characterization of subsurface geologic reservoirs. We determine the porosity and average grain size of a sequence of stratigraphic layers of Navajo Sandstone that are then used in a critical state model to infer plastic yield envelopes for the layers. Pure compaction bands are formed in layers having the largest average grain sizes (0.42–0.45 mm) and porosities (28%), and correspondingly the smallest values of critical pressure (-22 MPa) in the sequence. The results suggest that compaction bands formed in these layers after burial to -1.5 km depth in association with thrust faulting beneath the nearby East Kaibab monocline, and that hardening of the yield caps accompanied compactional deformation of the layers.

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Richard A. Schultz, Chris H. Okubo, Haakon Fossen. 2010-11-20. Porosity and grain size controls on compaction band formation in Jurassic Navajo Sandstone. https://doi.org/10.1029/2010gl044909

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