--> ABSTRACT: Depositional Controls on Permeability in an Eolian Sandstone Sequence, Page Sandstone, Northern Arizona, by Mark A. Chandler; #91038 (2010)

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Depositional Controls on Permeability in an Eolian Sandstone Sequence, Page Sandstone, Northern Arizona

Mark A. Chandler

Eolian reservoirs are typically characterized as homogeneous sandstone sequences. However, studies of modern eolian environments reveal that they consist of a hierarchy of facies which intermingle, resulting in the deposition of complex sandstone sequences that have heterogeneous characteristics. This study was conducted to delineate those depositional features in a "typical" eolian sandstone formation (Page sandstone, northern Arizona) that exhibit heterogeneous features in outcrop and to determine if these features cause anisotropic fluid flow in the sequence. It was found that the heterogeneity was a result of the coalescing of 4 distinct stratification types: grainflow, wind-ripple, interdune, and extradune deposits. Permeability measurements were taken to determine i these stratification types had unique fluid flow properties. It was discovered that extradune, interdune, wind-ripple, and grainflow strata increased in permeability mode and range. Several thousand permeability measurements were taken with a newly developed, portable field permeameter. These permeability measurements reveal that patterns of permeability can be distinguished which are directly related to depositional patterns. The relationship of permeability to stratification type and to stratigraphic organization indicates that depositional models can be used to interpret fluid flow in eolian sandstone reservoirs. Models have been constructed for some common eolian depositional styles. Such models are useful in designing simulations of reservoir production performance and for enhanced oil recovery procedures. It is likely that permeability/stratification style correlations similar to those seen in eolian deposits exist for other depositional environments. These detailed interrelationships between stratigraphic characteristics and fluid flow properties are key to accurate predictions of reservoir production potential.

AAPG Search and Discovery Article #91038©1987 AAPG Annual Convention, Los Angeles, California, June 7-10, 1987.