Changes

Eolian deposits include dune, interdune, sand sheets (marginal to dune complex), and extradune (noneolian) lateral deposits.<ref name=pt06r2 />) Dune deposits comprise the major sedimentary bodies in eolian successions. All are characterized by large scale [[cross-stratification]] in which foreset dips range up to 35°. Associated deposits may include those of wadi (fluvial), playa (lacustrine), and sabkha (arid tidal flat) origin.

Eolian deposits include dune, interdune, sand sheets (marginal to dune complex), and extradune (noneolian) lateral deposits.<ref name=pt06r2 />) Dune deposits comprise the major sedimentary bodies in eolian successions. All are characterized by large scale [[cross-stratification]] in which foreset dips range up to 35°. Associated deposits may include those of wadi (fluvial), playa (lacustrine), and sabkha (arid tidal flat) origin.

In the subsurface, eolian sandstones generally comprise thickly bedded sequences with few major interstratified shales. The sequences tend to be uniform and lack discernible coarsening- or fining-upward trends and, thus, exhibit blocky to weakly serrated gamma ray, SP, and resistivity log profiles The well-bedded and high angle cross stratified nature of eolian sandstones promotes reliable results from [[dipmeter]] logs. Dune and interdune deposits can often be distinguished and paleowind directions inferred using correctly processed dipmeter data.<ref name=pt06r80>Lupe, R., Ahlbrandt, T. S., 1979, Sediments of the ancient eolian environment—reservoir inhomogeneity, in McKee, E., D., ed., A Study of Global Sand Seas: U., S. Geological Survey Professional Paper 1052, p. 241–252.</ref>

In the subsurface, eolian sandstones generally comprise thickly bedded sequences with few major interstratified shales. The sequences tend to be uniform and lack discernible coarsening- or fining-upward trends and, thus, exhibit blocky to weakly serrated gamma ray, SP, and resistivity log profiles The well-bedded and high angle cross stratified nature of eolian sandstones promotes reliable results from [[Dipmeter analysis|dipmeter]] logs. Dune and interdune deposits can often be distinguished and paleowind directions inferred using correctly processed dipmeter data.<ref name=pt06r80>Lupe, R., Ahlbrandt, T. S., 1979, Sediments of the ancient eolian environment—reservoir inhomogeneity, in McKee, E., D., ed., A Study of Global Sand Seas: U., S. Geological Survey Professional Paper 1052, p. 241–252.</ref>

Eolian sandstones generally comprise excellent reservoir intervals but often possess complex [[porosity]] and [[permeability]] variations. They are commonly anisotropic with regard to the flow of fluids and exhibit greater horizontal than vertical permeability because of their pronounced lamination.<ref name=pt06r154>Weber, K. J., 1987, Computation of initial well productivities in aeolian sandstone on the basis of a geological model, Leman Gas field, U., K., in Tillman, R. W., Weber, K. J., eds., Reservoir Sedimentology: SEPM Special Publication 40, p. 335–354.</ref>

Eolian sandstones generally comprise excellent reservoir intervals but often possess complex [[porosity]] and [[permeability]] variations. They are commonly anisotropic with regard to the flow of fluids and exhibit greater horizontal than vertical permeability because of their pronounced lamination.<ref name=pt06r154>Weber, K. J., 1987, Computation of initial well productivities in aeolian sandstone on the basis of a geological model, Leman Gas field, U., K., in Tillman, R. W., Weber, K. J., eds., Reservoir Sedimentology: SEPM Special Publication 40, p. 335–354.</ref>