论文部分内容阅读
Chert of the Upper Sinian Doushantuo Formation near Changyang, western Hubei, China, contains an exceptionally well-preserved assemblage of spinose, spheroidal, and filamentous microfossils belonging to nineteen species. In this assemblage at least fifteen taxa are recognised to be plankton and only four to be microbenthos. The existing of large acanthomorphic acritarchs and a small number of microbenthos (matbuilding cyanobacteria) suggest an open coastal marine depositional environment. In comparison with probable coeval assemblages described from the Baklia Formation Prins Karls Forland, Svalbard (Knoll, 1992a) and the Biskopasen Conglomerate, Norway (Spjeldnaes 1963, 1967; Vidal, 1990), the Doushantuo microfossils (which have similar taxa) are remarkably abundant, diverse, and well-preserved. These data demonstrate the broad geographical distribution of pre-Ediacarian microbial taxa and further validate the use of acritarchs for the correlation of pre-Ediacarian successions.
Chert of the Upper Sinian Doushantuo Formation near Changyang, western Hubei, China, contains an exceptionally well-and-setting assemblage of spinous, spheroidal at nineteen species. In this assemblage at least fifteen taxa are recognized to be plankton and only four to be microbenthos. The existing of large acanthomorphic acritarchs and a small number of microbenthos (matbuilding cyanobacteria) suggest an open coastal marine depositional environment. In comparison with probable coeval assemblages from the Baklia Formation Prins Karls Forland, Svalbard (Knoll, 1992a) and the Biskopasen Conglomerate, Norway (Spjeldnaes 1963, 1967; Vidal, 1990), the Doushantuo microfossils (which have similar taxa) are remarkably abundant, diverse, and well-preserved. These data demonstrate the broad geographical distribution of pre-Ediacarian microbial taxa and further validate the use of acritarchs for the correlation of pre-Ediacarian successions.