Topics of this volume include observational evidence of extreme climatic conditions; geochemical and coupled climate modeling studies, alternative hypotheses for explaining low-latitude glacial deposits; and the biosphere and extreme ...
Author: Gregory S. Jenkins
Publisher: American Geophysical Union
ISBN: UCSD:31822020686846
Category: Nature
Page: 229
View: 639
Topics of this volume include observational evidence of extreme climatic conditions; geochemical and coupled climate modeling studies, alternative hypotheses for explaining low-latitude glacial deposits; and the biosphere and extreme climatic conditions.
9 9 low - altitude Proterozoic Glaciation . Journal of Geophysical Research , 105 , 7357-7370 . JENKINS , G. S. 2004. High obliquity as an alternative hypothesis to early and late Proterozoic extreme climate conditions .
Author: Emmanuelle Arnaud
Publisher: Geological Society of London
ISBN: 1862393346
Category: Science
Page: 735
View: 167
In recent years, interest in Neoproterozoic glaciations has grown as their pivotal role in Earth system evolution has become increasingly clear. One of the main goals of the IGCP Project number 512 was to produce a synthesis of newly available information on Neoproterozoic successions worldwide. This Memoir consists of a series of overview chapters followed by site-specific chapters. The overviews cover key topics including the history of research on Neoproterozoic glaciations, identification of glacial deposits, chemostratigraphic techniques and datasets, palaeomagnetism, biostratigraphy, geochronology and climate modelling. The site specific chapters include reviews of the history of research on these rocks and up-to-date syntheses of the structural framework, tectonic setting, palaeomagnetic & geochronological constraints, physical, biological, and chemical stratigraphy, and descriptions of the glaciogenic and associated strata, including economic deposits.
In: Jenkins GS, McMenamin MAS, McKay CP, Sohl L (eds) The extreme Proterozoic: geology, geochemistry and climate. American Geophysical Union, Washington, DC. Geophys Monogr146: 161–181 Young GM, Church WR (1966) The Huronian system in ...
Author: Victor Melezhik
Publisher: Springer Science & Business Media
ISBN: 9783642296697
Category: Science
Page: 1552
View: 229
Earth’s present-day environments are the outcome of a 4.5 billion year period of evolution reflecting the interaction of global-scale geological and biological processes. Punctuating that evolution were several extraordinary events and episodes that perturbed the entire Earth system and led to the creation of new environmental conditions, sometimes even to fundamental changes in how planet Earth operated. Volume 3: Global Events and the Fennoscandian Arctic Russia - Drilling Earth Project represents another kind of illustrated journey through the early Palaeoproterozoic, provided by syntheses, reviews and summaries of the current state of our understanding of a series of global events that resulted in a fundamental change of the Earth System from an anoxic to an oxic state. The book discusses traces of life, possible causes for the Huronian-age glaciations, addresses radical changes in carbon, sulphur and phosphorus cycles during the Palaeoproterozoic, and provides a comprehensive description and a rich photo-documentation of the early Palaeoproterozoic supergiant, petrified oil-field. Terrestrial environments are characterised through a critical review of available data on weathered and calichified surfaces and travertine deposits. Potential implementation of Ca, Mg, Sr, Fe, Mo, U and Re-Os isotope systems for deciphering Palaeoproterozoic seawater chemistry and a change in the redox-state of water and sedimentary columns are discussed. The volume considers in detail the definition of the oxic atmosphere, possible causes for the oxygen rise, and considers the oxidation of terrestrial environment not as a single event, but a slow-motion process lasting over hundreds of millions of years. Finally, the book provides a roadmap as to how the FAR-DEEP cores may facilitate future interesting science and provide a new foundation for education in earth-science community. Welcome to the illustrative journey through one of the most exciting periods of planet Earth!
Author: Canada. Earth Physics BranchPublish On: 1971
The Proterozoic is overlain unconformably to the south and west of the Bay by the Ordovician - Silurian dolomite of the Ronning Group which is about 300 m thick , and in the extreme southwest corner of the area covered in Fig .
Author: Canada. Earth Physics Branch
Publisher:
ISBN: UOM:39015019244121
Category: Astronomy
Page:
View: 957
Results of astronomical and geophysical research carried on by this Observatory and published in various scientific journals.
Seilacher, A., 1992, Vendobionta and Psammocorallia: Lost constructions of Precambrian evolution, J. Geol. Soc. ... Xiao, S., 2004a, Neoproterozoic glaciations and the fossil record. in: The Extreme Proterozoic: Geology, Geochemistry, ...
Author: Shuhai Xiao
Publisher: Springer Science & Business Media
ISBN: 9781402052026
Category: Science
Page: 300
View: 247
This volume presents a sample of views and visions among some of the growing numbers of Neoproterozoic workers. It includes a set of multidisciplinary reviews on the Neoproterozoic fossil record, evolutionary developmental biology of animals, and molecular clock estimates of phylogenetic divergences. These topics are of continuing interest to geoscientists and bioscientists who are intrigued by the deep history of the Earth and its inhabitants.
Late Proterozoic to early Palaeozoic palaeomagnetism and the formation of Gondwanaland . ... In : JENKINS , G. S. , MCMENAMIN , M. A. , MCKAY , C. P. & SOHL , L. ( eds ) The Extreme Proterozoic : Geology , Geochemistry and Climate .
Author: Jonathan Craig
Publisher: Geological Society of London
ISBN: 1862392870
Category: Science
Page: 309
View: 639
Worldwide, Neoproterozoic successions are major hydrocarbon producers. In North Africa, large basins with significant surface outcrops and thick sedimen-tary fills are widespread. These basins are now emerging as potential sources of hydrocarbons and are attracting interest both from geological researchers and the oil and gas industry. This volume focuses on recent developments in the understanding and correla-tion of North African basin fills and explores novel approaches to prospecting for source and reservoir rocks. The papers cover aspects of petroleum prospectivity and age-equivalent global petroleum systems, Neoproterozoic tectonics and pa-laeogeography, sequence stratigraphy, glacial events and global climatic models, faunal and floral evolution and the deposition of early source rocks. The broader aim is to compare with, and learn from, well-studied Neoproterozoic successions globally, including major environmental change, the emergence of life, the global carbon cycle and implications for hydrocarbon exploration.
Petrology of the Proterozoic mafic dyke swarms of Uruguay and constraints on their mantle source composition. ... In: Jenkins, G., McKay, C., Sohl, L. and McMenamin, M.A.S. (Eds.), The extreme Proterozoic: geology, geochemistry and ...
Author: Claudio Gaucher
Publisher: Elsevier
ISBN: 0080932770
Category: Science
Page: 498
View: 175
The book deals with the record of important Neoproterozoic to Early Palaeozoic events in southwestern Gondwana, that heralded the Cambrian explosion and the dawn of modern ecosystems. It contains a detailed account of the Neoproterozoic to Cambrian geological record in a poorly-known part of the world, which is at the same time key to understand fundamental processes at the Proterozoic-Cambrian transition. The emphasis is placed on litho-, bio-, chemostratigraphy and magmatism. The palaeoclimatic, tectonic, evolutionary radiation and extinction events and associated mineralizations will be identified and discussed. A synthesis of all data is provided at the end of the book, integrating the data from all cratons and fold belts in southwestern Gondwana. The events will be individualized, their impact discussed and correlations between different successions both within and outside Gondwana proposed. The book is organized in three sections. Section one is an introduction to the neoproterozoic and Cambrian seen as a time of upheavals, extremes and innovations. Section two comprises nineteen chapters dealing with the neoproterozoic-Cambrian events in southwestern Gondwana. Section three will provide a synthesis on every major topic, and a critical assessment of the global implications of the presented data. * The book deals with the record of important Neoproterozoic to Early Palaeozoic events in southwestern Gondwana, that heralded the Cambrian explosion and the dawn of modern ecosystems. It contains a detailed account of the Neoproterozoic to Cambrian geological record in a poorly-known part of the world, which is at the same time key to understand fundamental processes at the Proterozoic-Cambrian transition. The emphasis is placed on litho-, bio-, chemostratigraphy and magmatism.
... McKay CP (eds) The extreme proterozoic: geology, geochemistry, and climate. American Geophysical Union (AGU), Washington, pp 199—214 Xiao S, Dong L (2006) On the morphological and ecological history of Proterozoic macroalgae.
Author: Gabriel Trueba
Publisher: Springer Science & Business Media
ISBN: 9781461467328
Category: Science
Page: 168
View: 106
This volume is a collection of the some of the most significant lectures that well-known experts presented at our two international “summits on evolution” (2005, 2009) as updated and revised chapters. The meetings took place on one of the large islands of the Galapagos archipelago (San Cristobal) at GAIAS (Galapagos Institute for the Arts and Sciences) of the Universidad San Francisco de Quito (USFQ), Ecuador. The main goal of the two Galapagos Summits on Evolution has been to bring together scientists and graduate students engaged in the study of evolution, from life’s origin to its current diversity. Because of their historical significance, the Galapagos are a unique venue for promoting comprehensive research on evolution and ecology and to make the research results available to students and teachers everywhere, but especially from developing countries. As shown by the enthusiastic attendance at both summits and the many suggestions to keep them continuing, the meetings have opened new opportunities for students from Ecuador and other Latin American countries to be inspired by some of the most brilliant minds in evolutionary science.
The lowest exposed thrust sheet is unnamed and river is extremely hazardous . The southeastern part of contains the Proterozoic Y Wilson Creek Gneiss and the the study area is accessible by gravel USFS road 117 . overlying Proterozoic Z ...
In: The Extreme Proterozoic: Geology, Geochemistry, and Climate. Geophysical Monograph Series, 146. A.G.U. 145–159. Xu, B., Jian, P. Zheng, H., Zou, H., Zhang, L. and Liu, D. (2005) U–Pb zircon geochronology and geochemistry of ...
Author: Michael J. Hambrey
Publisher: John Wiley & Sons
ISBN: 9781444304442
Category: Science
Page: 436
View: 236
Associating ice masses with the transport and deposition ofsediments has long formed a central theme in glaciology and glacialgeomorphology. The reason for this focus is clear, in that icemasses are responsible for much of the physical landscape whichcharacterizes the Earth's glaciated regions. This association alsoholds at a variety of scales, for example, from the grain-sizecharacteristics of small-scale moraines to the structuralarchitecture of large-scale, glacigenic sedimentary sequences inboth surface and subaqueous environments. This volume brings numerous state-of-the-art research contributionstogether, each relating to a different physical setting, spatialscale, process or investigative technique. The result is a diverseand interesting collection of papers by glaciologists, numericalmodellers and glacial geologists, which are all linked by the themeof investigating the relationships between the behaviour of icemasses and their resulting sedimentary sequences.