The Ecology of the Cambrian Radiation - Andrey Zhuravlev - Chapter 20 ppsx

... studies of the Middle-Late Cambrian may reveal diversity similar to that of the Early Cambrian. Nonetheless, some of the patterns presently observed may be real. The appearance in the Nemakit-Daldynian ... are long-ranging (table 20. 3), but Gemma and Korilophyton appear restricted to the lower part of the Early Cambrian. At present, therefore, the Nemakit-Daldyn...

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... 1995). The prob- lem of relating the two scales is complicated by the fact that the base of the Tom- motian was taken as the base of the Cambrian at 570 Ma in Harland et al. 1990. Since then, the ... interval; the substantial revision to the age of the base of the Cambrian period and other early Paleozoic stratigraphic boundaries; and, of course, the...

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... 2132 NEM TOMMO- TIAN ATDABA- NIAN BOTO- MAN TOYO- NIAN AM- GAN MARJU- MIAN STEP- TOEAN SUN- WAP- TAN DT 0.7080 0.7090 0.7100 40 50 60 70 80 20 40 20 40 60 80 100 120 5 10 60 15 5 10 15 20 100 545 535 200 300 400 500 600 700 90 40 50 60 70 525 ... 1981. The uniqueness of the Cambrian fauna. In M. E. Taylor, ed., Short Papers for the Second International Symposium on the...

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... quality of seawater, thereby allowing the radiation of di- verse phototrophic communities (Zhuravlev chapter 8; Burzin et al. chapter 10); how the appearance of framework-building organisms created ... theme of community considers the biotas in their ecologic context, from their di- versification to the development of planktonic, level-bottom, reef, hardground, and deep-w...

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... of the Innuitian Belt in the Cana- dian Arctic, which still await solution. There is no general agreement on the paleo- geographic boundaries of Siberia for the Vendian and Cambrian. The southern ... [Facies and stratig- raphy of the Vendian and Cambrian of the western East-European Platform], pp. 24 – 33. Tallin: Academy of Sciences of Esto- nian SSR. Brasier, M....

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... 1994. The period of evolution- ary failure and the dawn of evolutionary success: The record of biotic changes across the Precambrian -Cambrian bound- ary. In S. K. Donovan, ed., The Palaeobiol- ogy ... bulging of the crust and transgression of the platform proceeded. Com- parison of the 87 Sr/ 86 Sr record of the Ediacarian -Cambrian with that of the Cen...

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... indicators of the climatic and environmental changes that occurred during the Neoproterozoic- Cambrian transition. They also appear to reveal the occurrence of a discrete cold period in the Cambrian: the ... Sinian. Together with increasing evidence for a renewed cold period in the Cambrian, the isotopic record suggests the unique nature of the period. On the bas...

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... boundary is placed at the base of the Wang- konda Formation and at the base of the trace fossil–bearing sandstones of the Winulta Formation in the Stansbury Basin. The Precambrian -Cambrian boundary ... 1992. Ion-probe zircon dating of a mid-Early Cambrian tuff in South Australia. Journal of the Geological Society of London 149:185–192. Daily, B. 1972. The bas...

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... beds. DISCUSSION The Cambrian represents a critical point in the development of nearly all biofabrics. Near the base of the Cambrian, there was a significant shift in the nature of sedimen- tary fabrics. ... in the devel- opment of metazoan history, with the advent of skeletonization and the establishment of the Cambrian Evolutionary Fauna, it is an equally i...

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... 1996); how- ever, it is the taphonomic loss of “soft-bodied” constituents that stands as the over- arching bias of the fossil record. These typically unfossilized forms comprise a ma- jority of taxa ... of an early Paleo- zoic plankton and benthos, but they place the transition at the end of the Cambrian rather than the beginning. Certainly the Cambro-Ordovician tr...

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