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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.〔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.〕 The Nama Group is made of fluvial and shallow-water marine sediments, both siliciclastic and carbonate.〔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. 〕 "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: *Fish River Subgroup *Schwarzrand Subgroup * *Nomtsas Formation * *Urusis Formation * *Nudaus Formation *Kuibis Subgroup * *Zaris Formation * *Dabis Formation 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Nama Group」の詳細全文を読む スポンサード リンク
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