Duck Creek Limestone and Kiamichi Formation, undivided (TXKdk;0)

State	Texas
Name	Duck Creek Limestone and Kiamichi Formation, undivided
Geologic age	Phanerozoic \| Mesozoic \| Cretaceous-Early
Original map label	Kdk
Comments	Duck Creek--Limestone, aphanitic, in part bioclastic, locally burrowed, pyrite nodules up to 0.2 ft, beds 0.2-2 ft thick, pinch and swell, md. gray to yell gray; weathers dk gray with yell-brn patches. marine megafossils are Gryphaea and ammonites; thickness 30-100 ft. Kiamichi--clay and limestone in alternating units 0.1-5 ft thick; some sandstone.
Primary rock type	limestone
Secondary rock type	clay or mud
Other rock types
Lithologic constituents	Major Sedimentary > Carbonate > Limestone (Bed) Minor Sedimentary > Clastic > Mudstone > Claystone (Bed) Incidental Sedimentary > Clastic > Sandstone (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, 1972, Dallas sheet, Geologic Atlas of Texas, Bureau of Economic Geology, University of Texas at Austin, scale 1:250,000.
Geographic coverage	Bailey - Hockley - Lamb - Lynn