Nama Group

The Nama Group is a Vendian to Cambrian group of stratigraphic sequences deposited in the Nama foreland basin in central and southern Namibia. The Nama foreland basin is a peripheral foreland basin, and the Nama Group was deposited in two early basins, the Zaris and Witputs, to the north, while the South African Vanrhynsdorp Group was deposited in the southern third.[1] The Nama Group is made of fluvial and shallow-water marine sediments, both siliciclastic and carbonate.[2] La Tinta Group in Argentina is considered equivalent to Nama Group.[3]

"Nama-type preservation" is an Ediacaran type preservation that presents sandstone castings of fossil creatures in which organisms are preserved in three dimensions, within fine-grained beds that were deposited in single storm or mudflow events: an example is Ausia fenestrata.

Geologic sequence

Some major units of the Nama Group include:

See also

List of fossiliferous stratigraphic units in Namibia

References

  1. ↑ Gresse, P. G., G. J. B. Germs. The Nama foreland basin: sedimentation, major unconformity bounded sequences and multisided active margin advance. 1993, Precambrian Research, 63(3-4):247-252, 259-272.
  2. ↑ Saylor, Beverly Z., John P. Grotzinger, Gerard J. B. Germs. Sequence stratigraphy and sedimentology of the Neoproterozoic Kuibis and Schwarzrand Subgroups (Nama Group), southwestern Namibia. 1995 Precambrian Research 73:153-171.
  3. ↑ Iacumin, M.; Piccirillo, E.M.; Girardi, V.A.V.; Teixeira, W.; Bellieni, G.; Echeveste, H.; Fernández, R.; Pinese, J.P.P.; Ribot, A. (2001). "Early proterozoic calc-alkaline and middle proterozoic tholeiitic Dyke Swarms from Central–Eastern Argentina: petrology, geochemistry, Sr–Nd isotopes and tectonic implications". Journal of Petrology. 42 (11): 2109–2143.


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