Late Precambrian Microfossils
نویسندگان
چکیده
منابع مشابه
Interpreting Late Precambrian Microfossils
Chia-Wei Li et al. describe microfossils found in Doushantuo phosphate rocks from Guizhou Province, South China that are about 580 million years old (1). Well-preserved macroscopic multicellular fossils associated with prokaryotic and eukaryotic microfossils from the same source rocks have been documented in several studies (2– 6). The Doushantuo fossils are outstanding in both preservation qua...
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Ion microprobe measurements of carbon isotope ratios were made in 30 specimens representing six fossil genera of microorganisms petrified in stromatolitic chert from the approximately 850 Ma Bitter Springs Formation, Australia, and the approximately 2100 Ma Gunflint Formation, Canada. The delta 13C(PDB) values from individual microfossils of the Bitter Springs Formation ranged from -21.3 +/- 1....
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A broad variety of body plans and subplans appear during a period of perhaps 8 million years (my) within the Early Cambrian, an unequaled explosion of morphological novelty, the ancestral lineages represented chiefly or entirely by trace fossils. Evidence from the fossil record can be combined with that from molecular phylogenetic trees to suggest that the last common ancestor of (i) protostome...
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Organically preserved algal microfossils from the Ringwood evaporite deposit in the Gillen Member of the Bitter Springs Formation (late Precambrian of central Australia) are of small size, low diversity, and probable prokaryotic affinities. These rather primitive characteristics appear to reflect the stressful conditions that prevailed in a periodically stagnant, hypersaline lagoon. This assemb...
متن کاملLate Precambrian oxygenation; inception of the clay mineral factory.
An enigmatic stepwise increase in oxygen in the late Precambrian is widely considered a prerequisite for the expansion of animal life. Accumulation of oxygen requires organic matter burial in sediments, which is largely controlled by the sheltering or preservational effects of detrital clay minerals in modern marine continental margin depocenters. Here, we show mineralogical and geochemical evi...
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ژورنال
عنوان ژورنال: Geological Magazine
سال: 1977
ISSN: 0016-7568,1469-5081
DOI: 10.1017/s0016756800036700