Iron Formations as Palaeoenvironmental Archives PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Iron Formations as Palaeoenvironmental Archives PDF full book. Access full book title Iron Formations as Palaeoenvironmental Archives by Kaarel Mänd. Download full books in PDF and EPUB format.
Author: Kaarel Mänd
Publisher: Cambridge University Press
ISBN: 1009002279
Category : Science
Languages : en
Pages : 66
Get Book Here
Book Description
Ancient iron formations - iron and silica-rich chemical sedimentary rocks that formed throughout the Precambrian eons - provide a significant part of the evidence for the modern scientific understanding of palaeoenvironmental conditions in Archaean (4.0–2.5 billion years ago) and Proterozoic (2.5–0.539 billion years ago) times. Despite controversies regarding their formation mechanisms, iron formations are a testament to the influence of the Precambrian biosphere on early ocean chemistry. As many iron formations are pure chemical sediments that reflect the composition of the waters from which they precipitated, they can also serve as nuanced geochemical archives for the study of ancient marine temperatures, redox states, and elemental cycling, if proper care is taken to understand their sedimentological context.
Author: Kaarel Mänd
Publisher: Cambridge University Press
ISBN: 1009002279
Category : Science
Languages : en
Pages : 66
Get Book Here
Book Description
Ancient iron formations - iron and silica-rich chemical sedimentary rocks that formed throughout the Precambrian eons - provide a significant part of the evidence for the modern scientific understanding of palaeoenvironmental conditions in Archaean (4.0–2.5 billion years ago) and Proterozoic (2.5–0.539 billion years ago) times. Despite controversies regarding their formation mechanisms, iron formations are a testament to the influence of the Precambrian biosphere on early ocean chemistry. As many iron formations are pure chemical sediments that reflect the composition of the waters from which they precipitated, they can also serve as nuanced geochemical archives for the study of ancient marine temperatures, redox states, and elemental cycling, if proper care is taken to understand their sedimentological context.
Author: Victor Melezhik
Publisher: Springer Science & Business Media
ISBN: 3642296823
Category : Science
Languages : en
Pages : 503
Get Book Here
Book Description
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 punctuated by several extraordinary events and episodes that perturbed the entire Earth system. One of the earliest and arguably greatest of these events was a substantial increase (orders of magnitude) in the atmospheric oxygen abundance, sometimes referred to as the Great Oxidation Event. Volume 1: The Palaeoproterozoic of Fennoscandia as Context for the Fennoscandian Arctic Russia - Drilling Earth Project describes the implementation of the FAR-DEEP drilling project in Arctic Russia. It summarises the knowledge of more than 50 years of largely Russian-led fieldwork, information hitherto virtually unavailable in the west, and provides geological description of drilling areas with an overwhelming illustration of rocks by high-quality, representative photographs. The volume offers a comprehensive review and rich photo-illustration of palaeotectonic, palaeogeographic and magmatic evolution of the Fennoscandian Shield in the early Palaeoproterozoic, and link the evolution of the shield to the emergence of an aerobic Earth system. The volume unfolds the event-based Fennoscandian chronostratigraphy and discusses the chronology of the Palaeoproterozoic global events as the base for a new subdivision of Palaeoproterozoic time. Welcome to the illustrative journey through one of the most exciting periods of planet Earth!
Author: Edward T. Tipper
Publisher: Cambridge University Press
ISBN: 1108998542
Category : Science
Languages : en
Pages : 34
Get Book Here
Book Description
Magnesium is a major constituent in silicate and carbonate minerals, the hydrosphere and the biosphere. Magnesium is constantly cycled between these reservoirs. Since each of the major planetary reservoirs of magnesium have different magnesium isotope ratios, there is scope to use magnesium isotope ratios to trace 1) the processes that cycle Magnesium at a spatial scales from the entire planet to microscopic and 2) the relative fluxes between these reservoirs. This review summarises some of the key motivations, successes and challenges facing the use of magnesium isotopes to construct a budget of seawater magnesium, present and past.
Author: B. Lynn Ingram
Publisher: Cambridge University Press
ISBN: 1108998356
Category : Science
Languages : en
Pages : 51
Get Book Here
Book Description
Studies of Sr isotopic composition of thousands of samples of marine sediments and fossils have yielded a curve of 87Sr/86Sr versus age for seawater Sr that extends back to 1 billion years. The ratio has fluctuated with large amplitude during this time period, and because the ratio is always uniform in the oceans globally at any one time, it is useful as a stratigraphic correlation and age-dating tool. The ratio also appears to reflect major tectonic and climatic events in Earth history and hence provides clues as to the causes, timing, and consequences of those events. The seawater 87Sr/86Sr ratio is generally high during periods marked by continent-continent collisions, and lower when continental topography is subdued, and seafloor generation rates are high. There is evidence that major shifts in the seawater ratio can be ascribed to specific orogenic events and correlate with large shifts in global climate.
Author: Anne-Sofie Ahm
Publisher: Cambridge University Press
ISBN: 100903362X
Category : Science
Languages : en
Pages : 48
Get Book Here
Book Description
Over million-year timescales, the geologic cycling of carbon controls long-term climate and the oxidation of Earth's surface. Inferences about the carbon cycle can be made from time series of carbon isotopic ratios measured from sedimentary rocks. The foundational assumption for carbon isotope chemostratigraphy is that carbon isotope values reflect dissolved inorganic carbon in a well-mixed ocean in equilibrium with the atmosphere. However, when applied to shallow-water platform environments, where most ancient carbonates preserved in the geological record formed, recent research has documented the importance of considering both local variability in surface water chemistry and diagenesis. These findings demonstrate that carbon isotope chemostratigraphy of platform carbonate rarely represent the average carbonate sink or directly records changes in the composition of global seawater. Understanding what causes local variability in shallow-water settings, and what this variability might reveal about global boundary conditions, are vital questions for the next generation of carbon isotope chemostratigraphers.
Author: J. William Schopf
Publisher: Cambridge University Press
ISBN: 9780521366151
Category : Science
Languages : en
Pages : 1408
Get Book Here
Book Description
First published in 1992, The Proterozoic Biosphere was the first major study of the paleobiology of the Proterozoic Earth.
Author: John Ridley
Publisher: Cambridge University Press
ISBN: 1107244765
Category : Science
Languages : en
Pages : 411
Get Book Here
Book Description
Mapping closely to how ore deposit geology is now taught, this textbook systematically describes and illustrates the major ore deposit types, linking this to their settings in the crust and the geological factors behind their formation. Written for advanced undergraduate and graduate students with a basic background in the geosciences, it provides a balance of practical information and coverage of the relevant geological sciences, including petrological, geochemical, hydrological and tectonic processes. Important theory is summarized without unnecessary detail and integrated with students' learning in other topics, including magmatic processes and sedimentary geology, enabling students to make links across the geosciences. Students are supported by further reading, a comprehensive glossary, and problems and review questions that test the application of theoretical approaches and encourage students to use what they have learnt. A website includes visual resources and combines with the book to provide students and instructors with a complete learning package.
Author: Télesphore Sime-Ngando
Publisher: Springer
ISBN: 3319399616
Category : Science
Languages : en
Pages : 422
Get Book Here
Book Description
This book represents the first multidisciplinary scientific work on a deep volcanic maar lake in comparison with other similar temperate lakes. The syntheses of the main characteristics of Lake Pavin are, for the first time, set in a firmer footing comparative approach, encompassing regional, national, European and international aquatic science contexts. It is a unique lake because of its permanently anoxic monimolimnion, and furthermore, because of its small surface area, its substantially low human influence, and by the fact that it does not have a river inflow. The book reflects the scientific research done on the general limnology, history, origin, volcanology and geological environment as well as on the geochemistry and biogeochemical cycles. Other chapters focus on the biology and microbial ecology whereas the sedimentology and paleolimnology are also given attention. This volume will be of special interest to researchers and advanced students, primarily in the fields of limnology, biogeochemistry, and aquatic ecology.
Author: D.P. Le Heron
Publisher: Geological Society of London
ISBN: 1786203979
Category : Science
Languages : en
Pages : 289
Get Book Here
Book Description
Understanding the sedimentary and geophysical archive of glaciated margins is a complex task that requires integration and analysis of disparate sedimentological and geophysical data. Their analysis is vital for understanding the dynamics of past ice sheets and how they interact with their neighbouring marine basins, on timescales that cannot be captured by observations of the cryosphere today. As resources, sediments deposited on the inner margins of glaciated shelves also exhibit resource potential where more sand-dominated systems occur, acting as reservoirs for both hydrocarbons and water. This book surveys the full gamut of glaciated margins, from deep time (Neoproterozoic, Ordovician and Carboniferous–Permian) to modern high-latitude margins in Canada and Antarctica. This collection of papers is the first attempt to deliberately do this, allowing not only the similarities and differences between modern and ancient glaciated margins to be explored, but also the wide spectrum of their mechanisms of investigation to be probed. Together, these papers offer a high-resolution, spatially and temporally diverse blueprint of the depositional processes, ice sheet dynamics, and basin architectures of the world’s former glaciated margins; a vital resource in advancing understanding of our present and future marine-terminating ice sheet margins.
Author: Alcides N. Sial
Publisher: John Wiley & Sons
ISBN: 1119382483
Category : Science
Languages : en
Pages : 318
Get Book Here
Book Description
Winner of the 2020 PROSE Award for Earth Science! Exploring environmental changes through Earth’s geological history using chemostratigraphy Chemostratigraphy is the study of the chemical characteristics of different rock layers. Decoding this geochemical record across chronostratigraphic boundaries can provide insights into geological history, past climates, and sedimentary processes. Chemostratigraphy Across Major Chronological Boundaries presents state-of-the-art applications of chemostratigraphic methods and demonstrates how chemical signatures can decipher past environmental conditions. Volume highlights include: Presents a global perspective on chronostratigraphic boundaries Describes how different proxies can reveal distinct elemental and isotopic events in the geologic past Examines the Archaean-Paleoproterozoic, Proterozoic-Paleozoic, Paleozoic-Mesozoic, and Mesozoic-Paleogene boundaries Explores cause-and-effect through major, trace, PGE, and REE elemental, stable, and radiogenic isotopes Offers solutions to persistent chemostratigraphic problems on a micro-global scale Geared toward academic and researchgeoscientists, particularly in the fields of sedimentary petrology, stratigraphy, isotope geology, geochemistry, petroleum geology, atmospheric science, oceanography, climate change and environmental science, Chemostratigraphy Across Major Chronological Boundaries offers invaluable insights into environmental evolution and climatic change. Read the Editors' Vox: https://eos.org/editors-vox/unravelling-the-past-using-elements-and-isotopes
