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Petrography Geochemical And Isotopic Analysis In Live And Fossil Coral Skeletons And Speleothems For Paleoclimate Reconstructions And Environmental Monitoring In The Mediterranean Region
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Book Synopsis Petrography, Geochemical and Isotopic Analysis in Live and Fossil Coral Skeletons and Speleothems for Paleoclimate Reconstructions and Environmental Monitoring in the Mediterranean Region by : Paolo Montagna
Download or read book Petrography, Geochemical and Isotopic Analysis in Live and Fossil Coral Skeletons and Speleothems for Paleoclimate Reconstructions and Environmental Monitoring in the Mediterranean Region written by Paolo Montagna and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Plinius written by and published by . This book was released on 2005 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Paleoaltimetry written by Matthew J. Kohn and published by Walter de Gruyter GmbH & Co KG. This book was released on 2018-12-17 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: Volume 66 of Reviews in Mineralogy and Geochemistry is based on a two day short course entitled Paleoaltimetry: Geochemical and Thermodynamic Approaches held prior to the Geological Society of American annual meeting in Denver, Colorado (October 26-27, 2007). This meeting and volume were sponsored by the Geochemical Society, Mineralogical Society of America, and the United States Department of Energy. Contents: The Significance of Paleotopography Stable Isotope-Based Paleoaltimetry: Theory and Validation Paleoelevation Reconstruction Using Pedogenic Carbonates Stable Isotope Paleoaltimetry in Orogenic Belts – The Silicate Record in Surface and Crustal Geological Archives Paleoaltimetry from Stable Isotope Compositions of Fossils A Review of Paleotemperature–Lapse Rate Methods for Estimating Paleoelevation from Fossil Floras Paleoaltimetry: A Review of Thermodynamic Methods Paleoelevation Measurement on the Basis of Vesicular Basalts Stomatal Frequency Change Over Altitudinal Gradients: Prospects for Paleoaltimetry Thermochronologic Approaches to Paleotopography Terrestrial Cosmogenic Nuclides as Paleoaltimetric Proxies
Book Synopsis Biogeochemical Approaches to Paleodietary Analysis by : Stanley H. Ambrose
Download or read book Biogeochemical Approaches to Paleodietary Analysis written by Stanley H. Ambrose and published by Springer Science & Business Media. This book was released on 2006-04-18 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of human diet brings together reseachers from diverse backgrounds ranging from modern human nutrition and biochemistry to the geochemistry of fossilized bones and teeth. The contributions to this volume grow out of the Fourth Advanced Seminar on Paleodiet and provide a forum for scholars with common interests to discuss the latest advances and interpretations and chart future directions for paleodietry research.
Book Synopsis Paleotemperature Analysis by : Robert Bowen
Download or read book Paleotemperature Analysis written by Robert Bowen and published by Elsevier. This book was released on 2013-10-22 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: Methods in Geochemistry and Geophysics, 2: Paleotemperature Analysis focuses on the paleotemperature-analytical method, including the use of oxygen isotopes in carbonate analysis and in advancing knowledge on paleoclimates. The manuscript first offers information on the isotopes of oxygen as climatic indicators and sampling of fossil organisms, as well as oxygen and paleotemperatures, belemnoidea, and other fossils. The book also ponders on chemical techniques and mass spectrometric methods. Discussions focus on thermal and acid decomposition of carbonates, slow formation of carbonate solids, precipitation of carbonate, and mass spectrometry. The text examines paleotemperature scales and magnesium and strontium concentrations. Topics include salinity, standards, magnesium and strontium contents, history of sea water, and Mccrea's carbonate paleotemperature scale. The publication also takes a look at paleozoic, Jurassic, cretaceous, and tertiary and Pleistocene paleotemperatures. The publication is a dependable reference for readers interested in paleotemperatures.
Book Synopsis Sr Isotopes in Seawater by : B. Lynn Ingram
Download or read book Sr Isotopes in Seawater written by B. Lynn Ingram and published by Cambridge University Press. This book was released on 2022-03-31 with total page 51 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Book Synopsis Marine Palaeoenvironmental Analysis from Fossils by : Dan W. J. Bosence
Download or read book Marine Palaeoenvironmental Analysis from Fossils written by Dan W. J. Bosence and published by Geological Society of America. This book was released on 1995 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume critically reviews the use of fossils for the analysis of palaeoenvironments. The papers are multi-disciplinary, drawing on a host of geochemical, palaeoecological and palaeontological methods from traditional taxonomic uniformitarianism to more recently developed geochemical isotopic analyses. The approach of the book is analytical rather than taxonomic, concentrating on a range of techniques. The common thread, however, is that it is palaeontological material that is being considered, whether it be identifiable body fossils, trace fossils, distinctive fossil associates, diagenetically unaltered material or organic compounds. Using a number of methods, and comparing their results, allows different environmental controls to be isolated and provides more information on the record of past environmental parameters. The volume focuses on the data obtained from organisms and their remains and will be of importance to sedimentologists, stratigraphers and palaeontolgists who need to maximize their palaeoenvironmental interpretations of depositonal environments, facies models, sequence stratigraphy and palaeoclimates.--Provided by publisher.
Book Synopsis Geochemical and Petrographic Insights from Speleothems by : Maria Isabel Peckover
Download or read book Geochemical and Petrographic Insights from Speleothems written by Maria Isabel Peckover and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Paleoclimate Models for Western North America as Inferred from Speleothem Isotope Records by : Feride Serefiddin
Download or read book Paleoclimate Models for Western North America as Inferred from Speleothem Isotope Records written by Feride Serefiddin and published by . This book was released on 2003 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: Oxygen and carbon isotope analysis of two Wisconsin age speleothems shows different δ18Oct (δ18O of calcite) records for their coeval period of growth. The growth rates for the speleothems also differ and suggest that local environmental factors may have produced the divergent isotopic variation. Spectral analysis of the oxygen isotope record reveals the presence of millennial-scale cycles and Heinrich events. Good correlation with speleothem isotope records from Missouri and Israel confirm that global climate is being recorded.
Book Synopsis Introductory Petrography of Fossils by : Alan S. Horowitz
Download or read book Introductory Petrography of Fossils written by Alan S. Horowitz and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is a book for beginners. Not geological beginners, because an introductory course in paleontology and some knowledge of the petrographic microscope is assumed, but for beginners in the study of the petrography of fossil constituents in sedimentary rocks. Fossils are studied for various reasons: 1) to provide chron ologic (time) frameworks, 2) to delineate rock units and ancient environments, or 3) to understand the past development (evolu tion) of living plants and animals. All of these uses may be at tained through petrographic studies of thin sections of fossils embedded in sedimentary rocks. Some knowledge of the appear ance of fossils in thin section is also fundamental for general stratigraphic studies, biofacies analyses, and is even useful in studying some metamorphic rocks. Commonly, fossils are essen tial for the delineation of carbonate rock types (facies or bio facies). We have written this book for sedimentary petrologists and stratigraphers, who routinely encounter fossils as part of their studies but who are not specialists in paleontology, and for students who are seeking a brief review and an introduction to the literature of the petrography of fossiliferous sedimentary rocks. Although experienced paleontologists may be appalled by the many generalized statements on size, shape, and principal fossil characters recited herein, we counter that we have had some success in introducing non-paleontologically oriented geologists to the use and identification of fossil constituents without using excessive paleontological terminology and detailed systematics.
Book Synopsis Isotopic Geochemistry and Paleobiology by : Christophe Lecuyer
Download or read book Isotopic Geochemistry and Paleobiology written by Christophe Lecuyer and published by Iste Press - Elsevier. This book was released on 2017-10-01 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: Isotopic Geochemistry and Paleobiology is a comprehensive book dedicated to the application of stable isotope geochemistry to extinct vertebrates that have no extant equivalent. With a strong focus on dinosaur palentology, the book examines how various aspect of dinosaur lifestyles such as their ecology (diet, living environment, reproduction), their physiology (body temperature regulation) and the climatic conditions under which they lived, can be inferred from the stable isotope composition of their fossilized mineralized tissues (bones, teeth). Examining the latest advances and research in stable isotope geochemistry, this book is a valuable resource for scientists, researchers and students in the field of Geosciences, Evolutionay Biology and Paleclimatology, who wish to broaden their knowledge in the anaylisis and interpretation of dinosaur fossil remains. This is the first comprehensive book dedicated to the application of stable isotope geochemistry to extinct vertebrates that have no extant equivalent (dinosaurs) Latest advances in stable isotope geochemistry applied to dinosaur paleontology
Book Synopsis Geochemical Proxies Preserved in Fossils and Lake Sediments by : Fajun Sun
Download or read book Geochemical Proxies Preserved in Fossils and Lake Sediments written by Fajun Sun and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation research has used geochemical tools to reconstruct paleoecology and paleoenvironment with the goal to better understand the effects of long-term climate change on terrestrial ecosystems and mammalian evolution in South and Southwest China and on storm activity in South Florida. The major results are summarized below: The role of climate change in the evolution and diversification of hominoids remains a hotly debated issue. Stable isotope analyses of fossil mammals that coexisted with the hominoids can provide insights into hominoid paleoenvironments and shed light on this debate. In this research, stable carbon and oxygen isotope analyses were performed on tooth enamel samples from a variety of Pleistocene mammals including pandas, deer, elephants, pigs, rhinos, and bovids from two hominoid fossil localities (Yugong Cave and Baxian Cave) in South China. Enamel-[delta]13C values indicate that most of the mammals living in the study area during the late Middle Pleistocene had C3-based diets but a small number of individuals consumed some C4 grasses. This indicates the presence of C4 plants in the region during the late Middle Pleistocene, most likely in patches of open areas in a predominantly forested environment. However, during the early Late Pleistocene, all the mammals examined had C3-based diets, except one bovid and one panda that may have ingested small amounts of C4 plants. This indicates a dense forested environment with little C4 grasses during the early Late Pleistocene. Like the Early Pleistocene pygmy panda (Ailuropoda microta) from Yanliang Cave, the late Middle Pleistocene Ailuropoda baconi from Yugong Cave and the early Late Pleistocene Ailuropoda melanoleuca from Baxian Cave had higher mean diet-[delta]13C values than other co-occurring herbivores, indicating they preferred relatively open forest habitats and had more restricted diets compared to other mammals. The reconstructed mean paleo-meteoric water [delta]18Ow values are lower than the annual average [delta]18Ow value of modern precipitation in the region, suggesting that the climatic conditions during the times when these Pleistocene mammals were alive were colder and/or wetter than today. In addition, [delta]18O values of the obligate drinkers (pigs, rhinos, bovids) display an overall decreasing trend, accompanied by increased range of [delta]18O variations, from the Early Pleistocene to the early Late Pleistocene. This suggests that the regional climate became colder and/or wetter, with increased seasonality, from the Early Pleistocene to the early Late Pleistocene, likely related to intensified glaciation. The change in climate to colder conditions may be responsible for the extinction of the Gigantopithecus in this region. The Late Miocene witnessed significant changes in climate globally and was an important time in the evolution of hominoids. In this research, the isotopic compositions of Late Miocene mammalian teeth and freshwater shells from Shuitangba (Yunnan Province, China) - an important refugium for hominoids, were analyzed and used to reconstruct paleoenvironmental conditions in the area. [delta]13C values of fossil enamel samples range from -15.5% to -1.0%, with a mean of -11.3 ± 2.3%, and [delta]18O values vary from -14.2 to -4.6%, averaging -9.7 ± 2.2%. Reconstructed diet-[delta]13C values for these fossil mammals indicate that although they fed mostly on C3 plants, many of them consumed some C4 vegetation. This suggests that the local ecosystem contained C4 grasses but was dominated by C3 plants. The intra-tooth [delta]18O variation of fossil herbivores is larger than what is found in modern herbivores. Reconstructed paleo-meteoric water [delta]18Ow values are on average lower than those inferred from modern samples and also lower than the average [delta]18Ow values of modern precipitation in the region. Similarly, [delta]18O values of fossil freshwater shells display a larger seasonal variation and are significantly lower than modern shells from Fuxian Lake in the same region. Thus, the [delta]18O data from both mammalian teeth and freshwater mollusk shells support a wetter climate, possibly with a stronger precipitation seasonality in the Late Miocene than today. Comparison of clumped isotope temperatures from fossil and modern shells suggests a mean annual temperature of ~15 to 16°C in the Shuitangba area in the Late Miocene, which is ~3 to 4°C higher than that of today. Taken together, our isotope results suggest that C4 grasses existed in local ecosystems in the area, likely in patches of grasslands or wooded grasslands in a mostly forested environment in the Late Miocene when the local and regional climate was warmer and wetter than today. Comparison of the [delta]13C records from Yunnan and the Siwalik region suggests that C4 biomass spread earlier in the Indian subcontinent on the southwest side of the Tibetan Plateau than in Yunnan on the southeast side of the Plateau. The transition from a relatively wet habitat to a more open and drier habitat is also more pronounced and begins earlier in the Siwalik region, relative to Yunnan. These regional differences in climate and ecosystem evolution may be linked to the unique growth history of the Himalayan-Tibetan Plateau. Coastal lake sediments are important archives to understand long-term variability of paleoclimate. A nearly 1700-year-long paleostorm record was reconstructed based on multiple organic geochemical proxies preserved in a sediment core from a coastal lake in South Florida. The OPGs data show that significant variations in [delta]13C, [delta]15N, C%, N% and C/N with depth, reflecting changes in the lake environment that affected the processes delivering water/sediment to the lake as well as biological productivity with the lake. Analysis of modern organic materials in the lakes and their surrounding areas shows that the major sources of sedimentary organic matter in the lake are aquatic and terrestrial C3 vegetation. Based on our proposed criteria, a total of 33 events were identified in our sediment core, including 10 seawater (SW) flooding events and 23 freshwater (FW) flooding events. The proxy storm record indicate shows two active periods of intense storm activities from 1540 to 1200 cal yr BP and from -30 to -68 cal yr BP (or 1980 to 2018 C.E.). An inactive period was also identified between 365 and -5 cal yr BP. One of the active periods (1540 to 1200 cal yr BP) coincides with a period of heightened hurricane activities in the grain-size-based paleorecord from Salt Pond in Massachusetts. This active period also correlates with elevated sea surface temperatures (SSTs) in both the Gulf of Mexico (GoM). The calm patterns observed in our record (365 to -5 cal yr BP) coincides with an ENSO-Ecuador record which indicates a distinct pattern of less intense ENSO events over the past 500 years. Our research provides new insights into the understanding of paleostorm activities in the sand-limited South Florida region.
Book Synopsis Reconstructing High-resolution Paleoclimate for Portions of the Last 250,000 Years from Cave of the Mounds Speleothems by : Cameron Jean Batchelor
Download or read book Reconstructing High-resolution Paleoclimate for Portions of the Last 250,000 Years from Cave of the Mounds Speleothems written by Cameron Jean Batchelor and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Pleistocene period was a time of Earth's History marked by 100-kyr paced glacial-interglacial cycles and dominated by the influence of polar glaciation that stimulated Earth system feedbacks. Climate archives that grew during the Pleistocene thus provide the opportunity to explore past climate variability during a time of known global forcings and when distinct climate transitions occurred. Other than ice cores - one of the most robust terrestrial climate archives used by the paleoclimate community - speleothem-based paleoclimate reconstructions provide some of the highest-resolution continental climate records. This is due to their ability to be precisely dated, relatively continuous growth potential that is uninterrupted by surficial erosional processes, and because they form within carbonate (karst) rocks which are located in a variety of locations from the low- to high-latitudes, and thus not restricted to one geographic location. For this dissertation, I use a collection of speleothem samples from a southwestern Wisconsin cave, Cave of the Mounds, to reconstruct paleoclimate for portions of the last 250,000 years. This dissertation seeks to (1) resolve high-resolution oxygen isotope (Îþ18O) records representative of mid-continental North America during former glacial and interglacial periods through the use of specialized imaging and mass spectrometry techniques, and (2) provide data that will characterize climate variability and regional climate response to distinct global forcings in a relatively data-sparse region of the world. Except for Chapter 1, which focuses on U-Th dating methods of speleothems, all chapters of this dissertation use specialized imaging (confocal laser fluorescent microscopy, CLFM) and mass spectrometry (secondary ion mass spectrometer, SIMS) techniques to produce high-resolution Îþ18O records during different time periods of the last 250,000 years. Each chapter focuses on a different time period of the last 250,000 years, specifically the Last Glacial Period (70-50 ka, respectively; Chapter 2), the Late Holocene (3-2 ka; Chapter 3), the Last Interglacial Period (122-118 ka, respectively; Chapter 4), and the Penultimate Interglacial Period (230-218 ka, respectively; Chapter 5).
Book Synopsis Clays in Crustal Environments by : Norbert Clauer
Download or read book Clays in Crustal Environments written by Norbert Clauer and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 513 pages. Available in PDF, EPUB and Kindle. Book excerpt: Clay minerals form in a wide variety of crustal environments, e.g. in soil profiles, in sediments at the surface and in deeply buried sedimentary deposits, and under regional, contact and hydrothermal metamorphism conditions. The book provides information about the dynamics of isotope systems in clays and helps us to understand the physical and chemical parameters in the transfer of masses within the crustal domain. Written for graduate students taking courses in sedimentary geochemistry, clay mineralogy, and soil mineralogy, the book will also appeal to scientists carrying out research on clay genesis and mass transfer in crustal environments.
Download or read book Geochronology written by Derek Vance and published by Geological Society of London. This book was released on 2003 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt: Isotope geochemistry has produced many technical developments recently that have revolutionised the potential information available on the tectonics of metamorphic belts from geochronology. This set of papers describes recent progress in integrating this new information with other datasets from metamorphic petrology on a mineral and sub-mineral scale.
Book Synopsis Evaluating Stable Isotope and Geochronologic Techniques for Paleoclimate Reconstruction by : Robin Brendan Trayler
Download or read book Evaluating Stable Isotope and Geochronologic Techniques for Paleoclimate Reconstruction written by Robin Brendan Trayler and published by . This book was released on 2018 with total page 165 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Stable isotope analysis has become the method of choice for many studies investigating the paleoecology and paleoclimate of fossil mammal faunas. While organic tissues (collagen, keratins, proteins) persist for less than 105 years highly mineralized tooth enamel is resistant to alteration and degradation and faithfully preserves its isotopic composition for millions (greater than than 106) years. Reconstructing past climates from these records relies on both understanding both micro-scale mechanisms of isotope incorporation into individual teeth, and macro-scale changes in isotope compositions over hundreds of thousands or millions of years. In this dissertation I address three questions. First, how does the geometry and timing of tooth enamel mineralization affect isotope compositions? Tooth enamel mineralization occurs in two stages with different geometries and proportions of chemical components. In chapter one I present oxygen isotope data and high-resolution major element compositional maps of forming tooth enamel to clarify the process of enamel mineralization. Oxygen isotope results show that enamel records the isotopic composition of only second stage mineralization. Given this, ideal enamel sampling strategies should follow the geometry of second stage mineralization. High resolution maps of calcium density for several teeth reveal that enamel mineralizes at a high angle relative to the underlying dentine, suggesting that existing techniques are appropriate. Second, how can geochronology and stratigraphic information be convolved to strengthen interpretations of paleoclimate proxy records? Many reconstructions of past climates rely on proxy records (e.g. pollen, isotope samples) distributed through a stratigraphic section. Interpreting these data in a global context relies on both the ability to determine the absolute age of some stratigraphic positions, and a model that describes the relationship between stratigraphic position and age, allowing the age of unknown positions to be determined. In chapter two I report new U-Pb ages for several volcanic tuffs from the Santa Cruz Formation of southern Argentina. U-Pb data commonly exhibit complexities which make existing age-depth models unsuitable. I modified an existing age-depth model to better account for variations in absolute age, relative age, and the complex age uncertainties that often arise from magmatic crystal populations. Finally, I present a case study from the Santa Cruz Formation, Argentina. Fossil rich sediments span the initiation of the mid-Miocene climatic optimum, the most recent period of greenhouse conditions in the Cenozoic. carbon isotope-based estimates of mean annual precipitation reveal a progressive aridification of Patagonia with precipitation decreasing prior to the mid-Miocene climatic optimum."--Boise State University ScholarWorks.
Download or read book Seasonality from Speleothems written by and published by . This book was released on 2013 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: Speleothems are carbonate cave deposits that can preserve a geochemical record of local climate as they grow. Oxygen isotope ratios and trace element concentrations in speleothem calcite provide important continental proxies of past climate change. Conventionally, geochemical analyses of speleothems are performed at a sampling resolution that corresponds to several decades or centuries of growth; as a result, seasonal climate change is averaged and information is lost. This thesis applies new, high-resolution analytical approaches to both pre-historic and modern speleothems from Soreq Cave (Israel) in order to unlock seasonal climate information over both decadal and millennial time-scales. In pre-historic Soreq Cave speleothems, a combination of ion microprobe analyses of oxygen isotope ratios (ơ18O) and imaging by confocal laser fluorescent microscope (CLFM) provides sub-annual-scale climate information from 34-1 ka. During this time period, distinct differences in both the pattern of fluorescent banding and the gradient of ơ18O measured in situ across single, annual growth-bands indicate changes in the seasonal climate of the Eastern Mediterranean region. Before 15 ka, results suggest a reduced gradient of seasonal precipitation relative to the annual cycle of wet and dry seasons that is apparent throughout the Holocene. Detailed analysis of the Younger Dryas termination reveals a rapid onset of environmental change; fluorescent bands indicate that, as recorded by local rainfall, the termination spanned a minimum of 12 years. Similar analyses in a modern Soreq speleothem (1990-2008) are used to test and calibrate interpretations of seasonal-resolution geochemistry. In addition to ion microprobe analyses of ơ18O and trace element concentrations, two continuous datasets were measured across the modern sample: trace element concentrations measured by laser-ablation ICP-MS and a fluorescence-intensity transect measured by CLFM. Correlations between these datasets are combined with modern rainfall and dripwater analyses to illustrate how seasonal climate signals are transmitted to speleothems in Soreq Cave. Given the wide geographic distribution of caves and the rarity of seasonal-resolution paleoclimate records, the methods developed in this dissertation represent an important new approach for assessing past changes in seasonal climate around the globe and the associated shifts in atmospheric circulation.
