The Ecology of the Cambrian Radiation - Andrey Zhuravlev - Chapter 14 pps

... origins of theCambrianfauna.Geology 25:303–306. Brett, C. E., W. D. Liddell, and K. L. Derstler. 1 4- C1099 8/10/00 2:13 PM Page 319 PART III Ecologic Radiation of Major Groups of Organisms 1 4- C1099 ... Debrenne and Zhuravlev 1996), suggesting deeper-water occurrence. In the Botoman, some microscleres are recognized, autapomorphic of the Tetracti- 1 4- C1099 8/10/00 2:13...

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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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... 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...

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... 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 ... restricted to the lower part of the Early Cambrian. At present, therefore, the Nemakit-Daldynian marks the appearance of the Cambrian flora” (Chuvashov an...

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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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... 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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... 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 base of the Cambrian and the first Cambrian ... 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 Sta...

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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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