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Showing 1 to 9 of 9 for “"Doushantuo Formation"”.
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Integrated High-resolution Stratigraphy of the Doushantuo Formation, South China
… shaped biological evolution remains elusive. The Doushantuo Formation in South China, radiometrically constrained between 635.2±0.6 and 551.1±0.7 Ma, is ideal for high-resolution interdisciplinary research, and has the potential to clarify the relationship between environmental and biological …
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Exceptional Preservation and Bias in the Fossil Record
… represent opposing forces acting on the information quality of the fossil record. Exceptionally preserved assemblages capture features of anatomy and components of assemblages not normally recorded in the fossil record. Systematic biases affecting the fossil record do the opposite, skewing …
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Chuaria, Vendotaenia, and the taphonomy of the Carbonaceous Compression
… Jiulongwan, Sixi, and Sifangtan sections of the Doushantuo Formation and Vendotaenia fossils from the Wuhe and Miaohe sections of the Denying Formation are microchemically analyzed in both plane view and cross section in order to gain a greater understanding of the makeup of carbonaceous …
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Studying Redox Conditions of Devonian and Neoproterozoic Oceans Using I/ca Proxy From Bulk Carbonate Rocks
… are generally stable and high in the Onondaga Formation but show large fluctuations in lower Marcellus strata. The pattern of redox changes is correlated to organic-rich shale deposition, sea-level changes and biotic transitions in Devonian marine systems. The range of I/Ca values of the core …
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Contributions and New Methods in Paleontology: Geochemical, Ultrastructural, and Microstructural Characterization of Archean, Proterozoic, and Phanerozoic Fossils
… the phosphatization taphonomic window of the Doushantuo Formation of South China, which is a prime example of exceptional preservation. Finally, the fourth primary research chapter reported here uses field emission scanning electron microscopy and environmental scanning electron microscopy in …
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Sedimentology and diagenesis of Ediacaran phosphorites from South China
… from the early Ediacaran (632 – 614 Ma) Doushantuo Formation at the Wanjiagou section, near Zhangcunping, Hubei Province in South China. Results suggest granular phosphorites were deposited during one to two episodes of reworking of pristine phosphorite hardgrounds, which originated …
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Contributions to Exceptional Fossil Preservation
… researchers must incorporate background information regarding the pre- and post-burial histories of exceptionally preserved fossils. In this context, my dissertation focuses on the environmental settings, diagenetic conditions, geomicrobiological activities, and weathering processes, which …
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Geochemical investigation of the co-evolution of life and environment in the Neoproterozoic Era
… pyrite from the Cryogenian Tiesi'ao and Datangpo formations. The second set of samples contains pyritic rims from the Ediacaran Doushantuo Formation; these pyrite rims are associated with fossiliferous chert nodules and do not have superheavy sulfur isotopes. For the superheavy pyrite, the models …
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Geochemical and Paleontological investigations of the Neoproterozoic-Cambrian Transition: Case Studies on geochemical clast provenance, emerging paleo redox proxies, and ambiguous dubiofossils
The transition from the Neoproterozoic to the early Cambrian world was a critical time in the co-evolution of life and the environment, when dramatic changes in the environment, including global glaciations and rising atmospheric oxygen levels precipitated the conditions in which variety of complex …