Breckenridge Limestone Member of Thrifty Formation of Cisco Group (TX*)
Breckenridge Limestone [unranked] in Harpersville Formation of Cisco Group (TX-local)
Breckenridge Limestone [unranked] in Markley Formation of Bowie Group (TX-local)
Late Pennsylvanian (Gzhelian; Virgilian)*
Named from Breckenridge, Stephens Co., Brazos River region, central northern TX (Plummer and Moore, 1922).
Type reference section: on Harris Veale property, near south city limits of Breckenridge, west of US Hwy 183, Stephens Co., Brazos River region, central northern TX. Lower part of section measured from base of Blach Ranch limestone at road level on west side US Hwy 183 westward to pond excavated in Breckenridge limestone at top of prominent escarpment (fig. 5, beds 1A-5A). Upper part of section offset westward along outcrop of massive mottled bed of Breckenridge (fig. 5, bed 5A); upper interval measured from base of bioclastic limestone bed of Breckenridge, exposed in gully 1, northwest 20 yards, then southwest to sandstone above Crystal Falls limestone at top of isolated hill (fig. 5, beds 5B-12). All three units of Breckenridge (beds 5A, B, and C) are partly exposed in gullies 2 and 3, beds 5B and 5C are best exposed in gully 1. Makes prominent escarpment in and about town of Breckenridge, Stephens Co., Brazos River region, central northern TX.
Fort Worth syncline*
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