Delaho Formation and unit 9 of Rawls Formation (TXMId;0)

State	Texas
Name	Delaho Formation and unit 9 of Rawls Formation
Geologic age	Phanerozoic \| Cenozoic \| Tertiary \| Miocene
Original map label	Md
Comments	sandstone and conglomerate, pebbles dominantly Tule Mountain Trachyandesite, basalt pebbles dominant in upper part to the south (in Emory Peak-Prisidio Slheet (1979); sandst. composed mostly of volcanic rock fragments; festoon crossbedding will developed; Smoky Creek Mbr. thickness as much as 1,100 ft. Lower unnamed member thickness about 1,100 ft, total about 2,200 ft thick. Unit 9 of Rawls Fm is redefined as Closed Canyon Formation, mostly sedimentary rock (fan alluvium and basin-fill), alkali basalt lavas, dikes, and small plugs, and rare, 5-m thick, rhyolitic or quartz trachytic ash-flow tuff that accumulated with early basin-and-range faulting between 25 and 18 Ma ago.
Primary rock type	sandstone
Secondary rock type	basalt
Other rock types	conglomerate
Lithologic constituents	Major Sedimentary > Clastic > Conglomerate (Flow) Sedimentary > Clastic > Sandstone (Flow) Incidental Igneous > Volcanic
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, 1979, Emory Peak--Presidio Sheet, Geologic Atlas of Texas, University of Texas at Austin. Henry, C.D., McDowell, F.W., Price, J.G., and Smyth, R.E., 1986, Geochronology of Tertiary igneous rocks, Trans-Pecos, Texas, in Price, J.G. and others, eds., Igneous geology of Trans-Pecos, Texas: The University of Texas at Austin, Bureau of Economic Ge