Ventioner Formation (TXPAv;0)

State	Texas
Name	Ventioner Formation
Geologic age	Phanerozoic \| Paleozoic \| Carboniferous Pennsylvanian [Missouri]
Original map label	IPv
Comments	interbedded shale, sandstone, siltstone, and limestone. Shale- gray, black, maroon weathers tan and reddish brown, silty, sandy, locally laminated, thick beds, ferruginous nodules locally common; many sandy and silty lenses and flaggy, thin beds w/ horiz. lamination, ripple cross-lamination, local load and flute casts; some small, sandy channel-fill bodies to 6 ft thick w/ woody debris; fossil beds w/ marine invertebrates uncommon, fine-grained plant debris abdt. Sandstone and shale--ss units closely spaced, sheetlike and massive beds, trough cross stratified channel-fill bodies with shale clasts and plant debris, fine to med-grained, interbedded with shale and laminated siltst., thickness 15 to 40 ft. Limestonr-- tan to yellow, fine- to med-grained, thin beds and nodular, bioclastic mostly with algae, crinoids, fusulinids, and brachipods; merges with Ranger Limestone in subsurface; thickness 10-15 ft. Thickness of Ventioner Formation (revised) 200 to 270 ft
Primary rock type	fine-grained mixed clastic
Secondary rock type	medium-grained mixed clastic
Other rock types	limestone
Lithologic constituents	Major Sedimentary > Clastic > Mixed-clastic > Sandstone-Mudstone (Bed) Minor Sedimentary > Clastic > Mixed-clastic > Siltstone-Mudstone (Bed) Incidental Sedimentary > Carbonate > Limestone (Bed)
Map references	Bureau of Economic Geology, 1992, Geologic Map of Texas: University of Texas at Austin, Virgil E. Barnes, project supervisor, Hartmann, B.M. and Scranton, D.F., cartography, scale 1:500,000
Unit references	Bureau of Economic Geology, 1987, Wichita Falls-Lawton Sheet, Geologic Atlas of Texas: University of Texas at Austin, Bureau of Economic Geology, scale 1:250,000.
Geographic coverage	Jack - Wise