Sandstone in the Travis Peak (Hosston) Formation has been extensively modified by burial diagenesis. Permeability in much of the formation has been reduced to less than 0.1 md as a result of compaction, extensive precipitation of authigenic minerals, and minor pressure solution. Thin zones of higher porosity and permeability occur mainly near the top of the formation; porosity and permeability decrease with depth below the top.

Permeability in a vuggy carbonate sequence can be related to particle size, separate-vug porosity, and interparticle porosity. Total porosity can be determined from neutron, acoustic, and density logs, but the distinction made between interparticle and separate-vug porosity using log responses has never been quantifiable. As a result, such distinction has never been integrated into permeability estimates drawn from log analysis.

Ground water that moves downward from aquifers in clastic rocks of the Triassic Dockum Group and Neogene Ogallala Formation dissolves bedded halite and anhydrite in the Upper Permian evaporite section along the perimeter of the Southern High Plains in the Texas Panhandle. Ground-water velocity in salt-dissolution zones beneath the Canadian River valley and Rolling Plains may be greater than ground-water velocity in salt-dissolution zones beneath the Southern High Plains because of greater hydraulic conductivity and greater hydraulic-head gradient.

Permian strata in the Palo Duro Basin consist of multicyclic sequences of carbonate, nodular and laminated anhydrite, bedded halite, chaotic mudstone-halite, and terrigenous clastic sediments. These evaporite lithofacies record deposition in a shallow-water marine evaporate shelf depositional system. Clastic sediment derived from surrounding highlands contributed aluminous detritus to the basin, including aluminum-rich smectite, illite, and mixed-layer illite/smectite clays.