Triassic Basin
TRIASSIC BASINS
- NEWARK SUPERGROUP
- DAN RIVER GROUP
- Trd -- DAN RIVER GROUP, UNDIVIDED - Basin-margin conglomerate and sandstone, red to brown, interfingering with basin-center sandstone and mudstone, green to brown. Conglomerate shown by pattern
- Trds - STONEVILLE FORMATION - Conglomerate, sandstone, and mudstone, lenticular and laterally-gradational bedding
- Trdc -- COW BRANCH FORMATION - Mudstone with minor sandstone, gray, laterally-continuous bedding. Intertongues with Stoneville and Pine Hall Formations
- Trdp -- PINE HALL FORMATION - Sandstone, mudstone, and conglomerate, yellowish orange to brown
- CHATHAM GROUP
- Trc -- CHATHAM GROUP, UNDIVIDED - Conglomerate, fanglomerate, sandstone, and mudstone. Conglomerate and fanglomerate shown by pattern
- Arkosic sandstone, tan, medium- to very coarse-grained, micaceous, not shown
- Sandstone and mudstone with thin interbeds of chert and impure limestone, not shown
- Arkosic sandstone and clayey sandstone, brown; interbedded with brown to dark-gray sandstone and mudstone, not shown
- Trcs -- SANFORD FORMATION - Conglomerate, fanglomerate, sandstone, and mudstone
- Trcc -- CUMNOCK FORMATION - Sandstone and mudstone, gray to black; coal beds and carbonaceous shale. Grades into Pekin and Sanford Formations.
- Trcp -- PEKIN FORMATION - Conglomerate, sandstone, and mudstone
INTRUSIVE ROCKS
- DIABASE - Dikes and sills, gray to black, not shown