The Dan River Group is a geologic group in Virginia and North Carolina associated with the initial rifting of the supercontinent Pangea. It is located on the southern end of a much larger rift valley sequence (the Newark Supergroup) which together formed the Central Atlantic Magmatic Province (CAMP); an extremely large flood basalt eruption that occurred around 201 Ma. It preserves fossils dating back to the Triassic period.

Formations

It contains six geological formations:

  • Stoneville Formation (cyclical red mudstone). Sedimentary layer around 600 ft.
  • Leaksville Formation (Predominantly red mudstone.)
  • Cow Branch Formation (cyclical fossiliferous black/dark grey mudstone with rare coarser lithologies). Sedimentary thickness is around 545 ft.
  • Dry Fork Formation (cyclical tan/red sandstone and grey/purple/red mudstone)
  • Walnut Cove Formation (cyclical black/grey mudstone, sandstone, and coal)
  • Pine Hall Formation (coarse tan sandstone and red mudstone). It's thickness ranges between 524-2,000 feet in depth.

Volcanism

While the exact extent of lava erupted in the Dan River formation is not known, there is evidence of diabase dikes/sills found here. These magma bodies heated the ground around them, causing sedimentary rocks and coal to alter; a process known as contact metamophisis. The extent and volume of magma is unknown due to no exposed dikes or sills at the surface.

See also

  • Various Contributors to the Paleobiology Database. . Archived from on 25 March 2022.