| State | Texas |
|---|---|
| Name | Wellborn Formation |
| Geologic age | Eocene |
| Lithologic constituents |
Major
Sedimentary > Clastic > Sandstone (Glauconitic)
Incidental
Sedimentary > Coal > Lignite (Bed)
Sedimentary > Clastic > Mudstone > Claystone (Bed)
|
| Comments | In north, central, and south Texas including Quaternary for all of west Texas- Sandstone, fine to coarse grained, lt gray, crossbedded, contains borings of worms and Ophiomorpha burrows and fossil shells; locally well indurated; thickness about 150 ft. In East Texas and Gulf Coast to Rio Grande- quartz sand, v. fine to fine grained, sl. glauconitic, increasingly glauconitic eastward (in Palestine Sheet (1968), interbeds of brown lignitic clay and lignite; lt. brown, weathers dk gray; marine megafossils locally; thickness 50 ft, feathers out eastward |
| Stratigraphic units | Carlos Sandstone member included |
| References | Bureau of Economic Geology, 1976, Crystal City-Eagle Pass Sheet, Geologic Atlas of Texas, University of Texas, Bureau of Economic Geology, scale 1:250,000.Bureau of Economic Geology, 1974, San Antonio Sheet, Geologic Atlas of Texas, University of Texas, Bureau of Economic Geology, scale 1:250,000.Bureau of Economic Geology, 1974, Seguin Sheet, Geologic Atlas of Texas, University of Texas, Bureau of Economic Geology, scale 1:250,000.Bureau of Economic Geology, 1967, Palestine Sheet, Geologic Atlas of Texas, Bureau of Economic Geology, University of Texas at Austin, scale 1:250,000.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. |
| NGMDB product | |
| Counties | Angelina - Atascosa - Brazos - Burleson - Fayette - Gonzales - Grimes - Houston - Karnes - Lee - McMullen - Madison - Polk - Trinity - Walker - Wilson |