LA-ICP-MS Trace Element Analysis of Planktonic Foraminifera and Application to Marine Isotope Stage 31 in the Southwest Pacific Ocean PDF Download

Author: Annette Bolton
Publisher:
ISBN:
Category : Climatic changes
Languages : en
Pages : 267

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Author: Lael Vetter
Publisher:
ISBN: 9781303540998
Category :
Languages : en
Pages :

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Planktic foraminifers are abundant in the surface ocean, and the calcite shells of fossil foraminifers form a major component of deep sea sediments. These shells comprise a primary archive of sea surface conditions through the Cenozoic, and measurements of stable isotope and trace element ratios are frequently used in paleoclimate reconstructions. Each individual foraminifer calcifies over the course of days or weeks, and the environmental conditions during its life are locked into the geochemistry of the shell. Typically, measurements pool numerous individual shells in a single, bulk analysis to obtain an estimate of mean environmental conditions. However, observations of living foraminifers indicate that contemporaneous individuals may occupy different depth habitats, and individual foraminifers may migrate vertically during their life cycle. The potential thus exists for a population of foraminifers to capture a range of environmental conditions, and for daily-scale environmental variations to be recorded in the intrashell geochemical heterogeneity of a single individual. This research explores novel analytical methods of measuring geochemical heterogeneity in trace element ratios and stable oxygen and carbon isotope values in the shell calcite of the extant planktic foraminifer Orbulina universa through live culture experiments (Chapters 1 and 2) and measurements on fossil shells (Chapters 3 and 4). Chapter 1 describes the results of a live culture experiment in which oxygen isotope ([delta]18O) and trace element (Ba) labels in synthetic seawater were incorporated into shell calcite during calcification in the laboratory. Chapter 2 describes the results of a similar live culture experiment where O. universa calcified in seawater with modified trace element (Ba, 18Sr) and carbon isotope ([delta]13C) values. Intrashell geochemical measurements were performed using Secondary Ion Mass Spectrometry (SIMS) for [delta]18O and [delta]13C, and laser ablation inductively coupled mass spectrometry (LA-ICP-MS) for trace element analyses. Intrashell trace element analyses were accurately measured with sub-μm resolution using LA-ICP-MS depth profiling. We demonstrate that the full amplitude of isotopic values (labeled and ambient) are resolvable within the spatial resolution of SIMS measurements (3 [mu]m for [delta]18O; 6 [mu]m for [delta]13C). Together, these experimental results provide a quantitative framework for interpreting intrashell [delta]18O, [delta]13C) , and trace element ratio measurements in field samples, and open the possibility for reconstructing daily-scale environmental changes from fossil foraminifer shells.The combination of multiple different geochemical measurements on fragments of the same shell permits researchers to extract novel information from each individual foraminifer. Additionally, a suite of contemporaneous fossil foraminifer shells preserves a record of a range of environmental conditions from different depths in the water column. These types of measurements provide a new dimension of information about the hydrography or stratification of the surface ocean during transient events, such as glacial meltwater entering the ocean. Chapter 3 describes the results of an experiment conducted on fossil specimens of O. universa where each shell was split into fragments and each fragment was subjected to different reagent cleaning protocols. Intrashell LA-ICP-MS depth profiles on shell fragments illustrate the differences between cleaning techniques, and illustrate a method for computing whole-shell Mg/Ca and Ba/Ca ratios from collected depth profiles. In Chapter 4, [delta]18O, Mg/Ca, and Ba/Ca measurements were combined on multiple O. universa shells from selected 1 cm intervals from a core in the Orca Basin, Gulf of Mexico, deposited during the last deglacation (~18 to 11 ka). These combined measurements enable the calculation of [delta]18O(seawater) and salinity for each individual and the reconstruction of water column hydrography during meltwater pulses from the Laurentide Ice Sheet. Results yield computed [delta]18O(water) values of Laurentide Ice Sheet meltwater, and provide key insight into the dynamics of the ice sheet during its collapse.

Author: Katharina Billups
Publisher:
ISBN:
Category :
Languages : en
Pages : 552

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Author: Edmund Charles Hathorne
Publisher:
ISBN:
Category : Foraminifera, Fossil
Languages : en
Pages :

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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: Tracy Ann Mashiotta
Publisher:
ISBN:
Category :
Languages : en
Pages : 372

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Author: John Benjamin Creech
Publisher:
ISBN:
Category : Foraminifera, Fossil
Languages : en
Pages : 236

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Author: Mike Walker
Publisher: John Wiley & Sons
ISBN: 1118700090
Category : Science
Languages : en
Pages : 311

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Book Description
This introductory textbook introduces the basics of dating, the range of techniques available and the strengths and limitations of each of the principal methods. Coverage includes: the concept of time in Quaternary Science and related fields the history of dating from lithostratigraphy and biostratigraphy the development and application of radiometric methods different methods in dating: radiometric dating, incremental dating, relative dating and age equivalence Presented in a clear and straightforward manner with the minimum of technical detail, this text is a great introduction for both students and practitioners in the Earth, Environmental and Archaeological Sciences. Praise from the reviews: "This book is a must for any Quaternary scientist." SOUTH AFRICAN GEOGRAPHICAL JOURNAL, September 2006 “...very well organized, clearly and straightforwardly written and provides a good overview on the wide field of Quaternary dating methods...” JOURNAL OF QUATERNARY SCIENCE, January 2007

Author: Ramadan A. Mohamed
Publisher: LAP Lambert Academic Publishing
ISBN: 9783659357329
Category :
Languages : en
Pages : 176

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Laser Ablation attached to inductively coupled plasma mass spectrometry (LA-ICP-MS) is widely accepted as a rapid and sensitive technique for trace element analysis of solid materials. Three different instruments are used: 1- a-The double focusing ICP-MS (JMS-PLASMAX2) is used for the analysis of rare earth elements in minerals as (monazite), and for rocks as (standard samples BCR-2, AGV-2), Also lead and strontium isotope ratios in tourmaline sample solution. b- A quadrupole (ELAN6000, Perkin Elmer) mass spectrometer. It was applied for the analysis of single grains of tourmaline sample for Sr and Pb isotope ratios and fused pellets for trace elements composition for different samples 2- Energy dispersive Scanning Electron microscope used for the analysis of zircon fused pellets and single grains. Rutherford back scattering spectrometer for the analysis of zircon fused pellets to ensure the homogeneity of the fused pellets, and LA-HR-ICP-MS (PLASMAX2) for trace elements in zircon fused pellets. 3- Ion exchange and ion chromatograph GBC for the separation of transition and rare earth elements in geological samples.

Author: G. P. Glasby
Publisher:
ISBN:
Category : Marine sediments
Languages : en
Pages : 62

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