Geologic Unit: Wellborn

Usage:

Wellborn Formation of Jackson Group (TX)
Wellborn Sandstone of Jackson Group (TX*)

Subunits:

(alphabetical) --all in TX: Bedias Sandstone Member, Carlos Sandstone Member.

Geologic age:

early Tertiary (late Eocene)*

Type section, locality, area and/or origin of name:

Named from Wellborn, Brazos Co., eastern TX (US geologic names lexicon, USGS Bull. 896).
Type locality: in vicinity of Wellborn, about 7 mi south-southeast of College Station, Brazos Co., TX. On cuesta, 0.25 mi southeast of crossroads at Wellborn, contact of lower 4 ft of Carlos Sandstone with brown clay of Renick's middle Wellborn is exposed in roadcuts in front of cemetery; 1.25 mi north of crossroad, cuts on road to College Station expose 5 ft of gray tuffaceous clayey siltstone of middle member grading down into 6 ft of gray silty very fine-grained thin-bedded sandstone of Renick's Bedias Sandstone; about 250 yds farther north basal 5 ft of Bedias Sandstone, containing prints of pelecypods in lower 2 ft, lies on clay of Caddell Formation (Eargle, 1959).

AAPG geologic province:

East Texas basin*
Gulf Coast basin*