The Ecology of the Cambrian Radiation - Andrey Zhuravlev - Chapter 16 potx

... Lingulida, and Acrotretida—ap- peared during the Early Cambrian, the Siphonotretida appeared in the Middle Cam- brian, and the Discinida arose at the end of the Cambrian. 1 6- C1099 8/10/00 2:17 PM Page ... only the distal end of the pedicle is embedded in the sediment; (2) there are no bioturba- tion features in the rock; and (3) soft-bodied preservation suggests a...

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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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... 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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... 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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... 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 Cenozoic (Derry et al. 1994) suggests that the ... close to the Precambrian -Cambrian boundary, and that at the base of the Tommotian) are associ- ated with widespread breaks in deposition. Further work is neede...

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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. ... 1994. The period of early evolutionary failure and the dawn of evo- lutionary success: The record of biotic changes across the Precambrian -Cambrian bound...

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... problems concerning the Precambrian -Cambrian boundary and the Cambrian fauna radia- tion. Journal of the Geological Society, Lon- don 149:593–598. Runnegar,B.1979. Originandevolutionof the class Rostroconchia. ... analy- ses of these entities are needed. However, the diversity pattern of their Cambrian Flora is congruent with that of the Early Cambrian Biota, as ha...

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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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