Calibration of the Planktonic Foraminiferal Mg/Ca Paleothermometer PDF Download

Author: Martha Clarke McConnell
Publisher:
ISBN:
Category :
Languages : en
Pages : 168

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Author: Cary Mock
Publisher: Newnes
ISBN: 0444536426
Category : Science
Languages : en
Pages : 3883

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The second revised edition of the Encyclopedia of Quaternary Science, Four Volume Set, provides both students and professionals with an up-to-date reference work on this important and highly varied area of research. There are lots of new articles, and many of the articles that appeared in the first edition have been updated to reflect advances in knowledge since 2006, when the original articles were written. The second edition will contain about 375 articles, written by leading experts around the world. This major reference work is richly illustrated with more than 3,000 illustrations, most of them in colour. Research in the Quaternary sciences has advanced greatly in the last 10 years, especially since topics like global climate change, geologic hazards and soil erosion were put high on the political agenda. This second edition builds upon its award-winning predecessor to provide the reader assured quality along with essential updated coverage Contains 357 broad-ranging articles (4310 pages) written at a level that allows undergraduate students to understand the material, while providing active researchers with a ready reference resource for information in the field. Facilitates teaching and learning The first edition was regarded by many as the most significant single overview of Quaternary science ever, yet Editor-in-Chief, Scott Elias, has managed to surpass that in this second edition by securing even more expert reviews whilst retaining his renowned editorial consistency that enables readers to navigates seamlessly from one unfamiliar topic to the next

Author: M. Kucera
Publisher: Elsevier
ISBN: 9780080447025
Category : Science
Languages : en
Pages : 318

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MARGO - Multiproxy Approach for the Reconstruction of the Glacial Ocean surface summarizes the results of the MARGO international working group, with the aim to develop an updated and harmonised reconstruction of sea surface temperatures and sea-ice extent of the Last Glacial Maximum oceans. The MARGO approach differs from previous efforts by developing and consistently applying measures of various aspects of reconstruction reliability, and by combining faunal and geochemical proxies. In 14 papers, the volume provides a comprehensive review of earlier work and a series of new, proxy-specific reconstructions based on census counts of planktonic foraminifera, diatoms, radiolaria and dinoflagellate cysts as well as on Mg/Ca measurements in planktonic foraminifera. The approach of harmonising the calibration and application of different proxies is described in detail, various paleothermometry techniques and their results are compared and the challenge of treating sparsely sampled data as the basis for ocean circulation models is addressed. The use of stable oxygen isotope composition of foraminiferal shells as a proxy for past sea water composition is comprehensively reassessed, and a new approach to the transfer function paleothermometer is presented. This volume represents a landmark contribution to the understanding of ice-age oceanography as well as the proxies used to reconstruct past ocean states. The results will form the basis for forcing and validation of ocean circulation models. New regional reconstructions of Last Glacial Maximum ocean temperatures and sea ice cover Compilation of new calibration and fossil datasets as well as documentation of techniques and approaches to paleoenvironmental reconstructions Comparison of techniques, proxies and modelling approaches

Author: William E. N. Austin
Publisher: Geological Society of London
ISBN: 9781862392571
Category : Medical
Languages : en
Pages : 206

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Most of our information about the evolution of Earth's ocean-climate system comes from the analysis of sediments laid down in the past. For example, the microfossil assemblage reflects the temperature, salinity and nutrient abundance of the water in which the organisms lived, while the chemical and isotopic composition of biogenic carbonates may be used to reconstruct past variations in the operation of the carbon cycle, as well as changes in ocean circulation. Nevertheless, understanding the link between these sediment variables (or 'proxies') and environmental conditions is not straightforward. This volume adopts a novel approach by bringing together palaeontologists, geochemists and palaeoceanographers, who contribute evidence that is required to better constrain these proxies. Topics include: (i) processes of biomineralization, and their effect on the chemical and isotopic composition of different organisms; (ii) proxy validation, including field, laboratory and theoretical studies; (iii) the links between modern and fossil organisms

Author: C. Hillaire-Marcel
Publisher: Elsevier
ISBN: 0080525040
Category : Science
Languages : en
Pages : 863

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The present volume is the first in a series of two books dedicated to the paleoceanography of the Late Cenozoic ocean. The need for an updated synthesis on paleoceanographic science is urgent, owing to the huge and very diversified progress made in this domain during the last decade. In addition, no comprehensive monography still exists in this domain. This is quite incomprehensible in view of the contribution of paleoceanographic research to our present understanding of the dynamics of the climate-ocean system. The focus on the Late Cenozoic ocean responds to two constraints. Firstly, most quantitative methods, notably those based on micropaleontological approaches, cannot be used back in time beyond a few million years at most. Secondly, the last few million years, with their strong climate oscillations, show specific high frequency changes of the ocean with a relatively reduced influcence of tectonics. The first volume addresses quantitative methodologies to reconstruct the dynamics of the ocean andthe second, major aspects of the ocean system (thermohaline circulation, carbon cycle, productivity, sea level etc.) and will also present regional synthesis about the paleoceanography of major the oceanic basins. In both cases, the focus is the “open ocean leaving aside nearshore processes that depend too much onlocal conditions. In this first volume, we have gathered up-to-date methodologies for the measurement and quantitative interpretation of tracers and proxies in deep sea sediments that allow reconstruction of a few key past-properties of the ocean( temperature, salinity, sea-ice cover, seasonal gradients, pH, ventilation, oceanic currents, thermohaline circulation, and paleoproductivity). Chapters encompass physical methods (conventional grain-size studies, tomodensitometry, magnetic and mineralogical properties), most current biological proxies (planktic and benthic foraminifers, deep sea corals, diatoms, coccoliths, dinocysts and biomarkers) and key geochemical tracers (trace elements, stable isotopes, radiogenic isotopes, and U-series). Contributors to the book and members of the review panel are among the best scientists in their specialty. They represent major European and North American laboratories and thus provide a priori guarantees to the quality and updat of the entire book. Scientists and graduate students in paleoclimatology, paleoceanography, climate modeling, and undergraduate and graduate students in marine geology represent the target audience. This volume should be of interest for scientists involved in several international programs, such as those linked to the IPCC (IODP – Integrated Ocean Drilling Program; PAGES – Past Global Changes; IMAGES – Marine Global Changes; PMIP: Paleoclimate Intercomparison Project; several IGCP projects etc.), That is, all programs that require access to time series illustrating changes in the climate-ocean system. Presents updated techniques and methods in paleoceanography Reviews the state-of-the-art interpretation of proxies used for quantitative reconstruction of the climate-ocean system Acts as a supplement for undergraduate and graduate courses in paleoceanography and marine geology

Author: M. A. Martínez Botí
Publisher:
ISBN:
Category :
Languages : en
Pages : 180

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Author: Ralf Schiebel
Publisher: Springer
ISBN: 3662502976
Category : Science
Languages : en
Pages : 358

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This book provides a comprehensive overview of the taxonomy, biology, sedimentation, and carbonate geochemistry of modern species. Students, early career and advanced scientists alike will profit from a broad synthesis of the current understanding of planktic foraminifers as an ecological indicator, biogeochemical factories, and proxies in paleoceanography. The classification of modern species is amply illustrated with electron and light microscope images of morphotypes, addresses the state-of-the-art of molecular genetics of species, and provides a detailed guide for any laboratory analyses. The biology of planktic foraminifers is extensively discussed in chapters dedicated to the cellular ultrastructure, nutrition, symbionts, reproduction, ontogeny, and test architecture. Building on the biological prerequisites, the distribution of planktic foraminifers is discussed at regional to global scale. The geochemistry and sedimentation of tests are considered in relation to the ecology of the living animal. In the final chapter, which examines the most common methods in planktic foraminifer research, hands-on information is provided on sampling, processing and analyzing samples in the laboratory, as well as selected established methods for data interpretation. The various topics discussed in this book are aimed at the application of planktic foraminifers as sensitive indicators of the changing climate and marine environment.

Author:
Publisher:
ISBN:
Category : Benthic animals
Languages : en
Pages : 128

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Magnesium calcium paleothermometry in benthic foraminifera is intended to provide a salinity-independent reconstruction of bottom water temperature. The temperature calibration is however, rather uncertain, due to evidence of additional carbonate saturation effects on Mg incorporation into benthic tests. The overarching goal of this thesis is to directly determine the magnitude of the carbonate saturation effect and the threshold at which this effect significantly alters temperature estimates based on the Mg/Ca content of benthic foraminiferal tests. My research has focused on using homothermal homohaline depth transects from the Norwegian Sea and Gulf of Mexico in the context of a global core top calibration. This thesis consists of 45 core tops from four cruises. In these transects, the relationship between carbonate saturation and Mg/Ca is not strongly pronounced, possibly due to the large variability in the data. As is, it does support the hypothesis that in saturated waters, temperature exerts the primary control on benthic foraminiferal Mg/Ca. A two-part global calibration equation has been constructed for under-(delta[CO3-2] 3 mu mol/kg) and over-saturated (delta[CO3-2] 3 mu mol/kg) waters. However, these equations produce unrealistic bottom water temperature reconstruction when applied to a downcore record in the eastern basin of the tropical Atlantic Ocean (1° 21'S 11° 58'W; 3912 m). These results suggest that further work is needed to improve the reliability of the Mg/Ca-T-delta[CO3-2] equation and to accurately determine the threshold at which delta[CO3-2] effects become pronounced. Likewise, future studies should look into using multi proxy approaches for correcting Mg/Ca-T estimates for saturation effects, such as the use of B/Ca measurements as a proxy for delta[CO3-2].

Author: Heinrich D Holland
Publisher: Academic Press
ISBN: 0080967116
Category : Science
Languages : en
Pages : 750

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After the discovery that elements were commonly composed of isotopes, there developed a range of studies of the variability of isotopic compositions in Earth materials, which was able to add to our understanding of Earth processes and history. This collection of chapters from the Treatise on Geochemistry describes the range of isotopic studies. The chapters are grouped into the following categories: light stable isotopes, radiogenic tracers, noble gases and radioactive tracers. The first three groups depend on mass spectrometric measurements. The section on radioactive tracers employs both radioactive counting techniques and the newly developed accelerator mass spectrometric techniques. Comprehensive, interdisciplinary and authoritative content selected by leading subject experts Robust illustrations, figures and tables Affordably priced sampling of content from the full Treatise on Geochemistry

Author: C. Bryan Gregor
Publisher: Wiley-Interscience
ISBN:
Category : Science
Languages : en
Pages : 298

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A concise review of the geochemical cycles of terrestrial evolution, written by well-known geochemists. Treatment is accessible, yet covers many geochemical specialties. Edited to provide an interdisciplinary approach for professionals and advanced students of geology, geochemistry, and earth and atmospheric sciences.