Simulating the Evolution of Fluid Underpressures in the Great Plains, by Incorporation of Tectonic Uplift and Tilting, with a Groundwater Flow Model

Figure 19

Permeability values selected by Senger and Fogg [31] for hydrologic units in a study of the Palo Duro Basin, Texas. Values range over seven orders of magnitude, from one darcy (D) to 0.1 microdarcies (uD). The left axis label shows equivalents for hydraulic conductivity in m d⁻¹ using a conversion factor of 1 D = 0.835 m d⁻¹. STP, standard temperature and pressure; Perm-Penn, Permian-Pennsylvanian. The ratio of vertical to horizontal permeability ranges from 0.01 to 1.0.