Author: Thomas S. Tobin
Publisher:
ISBN:
Category : Carbon
Languages : en
Pages : 151
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Book Description
This primary goal of this dissertation is to increase understanding of the end Cretaceous (or Cretaceous - Paleogene or K-Pg) mass extinction through the use of light stable isotope geochemistry. These studies attempt to examine any climatic and environmental changes that occurred around the K-Pg boundary, and might have contributed to the K-Pg mass extinction, specifically by examining isotopic records at high stratigraphic resolution around the boundary. Studies are completed in two field areas, the Antarctic Peninsula and eastern Montana, USA, both of which preserve the K-Pg boundary. While these works, like most scientific studies, lead to further questions that warrant investigation and confirmation, they generally support the idea the end Cretaceous mass extinction was more complicated than a simple asteroid strike. This dissertation is comprised of five scientific chapters as well as short introductory and concluding sections. The introduction explains the background and context behind each study, and the process by which I ultimately worked with a wide variety of co-authors to complete the various projects. The conclusion begins the process of examining the differences and similarities of each study, and explores further avenues of research to test some of the proposed hypotheses or reconcile potentially contradictory data. Four of the chapters are written as scientific manuscripts, while a fifth chapter details the work done as part of my astrobiology rotation. Chapter 1 (Tobin et al., 2011) outlines the discovery of analytical errors in the typical process of measuring carbonate stable isotopes (delta 13C and delta 18O) on small sample sizes of powder. Carbonate material is typically prepared using one of two methods, either by drilling using a high speed drill or micromill, or by crushing a sample using a mortar and pestle. Drilling produces a finer grain size of material, which is consequently more prone to being altered in its delta 18O value during a typical automated measurement process, while the sample is waiting in the queue to be analyzed. This chapter outlines the specific parameters under which this phenomenon occurs, and describes a correction procedure, though we encourage every lab to develop their own correction scheme. Chapter 2 (Tobin and Ward, submitted) is the second of two papers (in order of analysis and publication, but first presented here) that analyze and interpret delta 13C and delta 18O values from molluscan shell carbonate collected on the Antarctic Peninsula, though a small amount of fossil shell material was also used in Chapter 1. In this study, we examine trends in delta 13C for ammonites and other benthic mollusks using our own collections with added samples coming from collections currently housed at the Paleontological Research Institute (PRI). In both collections we find a notable offset in delta 13 C between ammonites and benthic mollusks, though good correspondence in delta 18O. Ultimately, the best interpretation of this pattern is that ammonites are incorporating more respired CO2 into their shell material, potentially from a higher metabolic rate. A more active lifestyle could potentially have increased the susceptibility of ammonites to an event like bolide impact at the end of the Cretaceous. Chapter 3 (Tobin et al., 2012) also looks at isotopic records, in this case focusing on delta 18O values, for fossil mollusks from Antarctica. Paleotemperature can generally be inferred from delta 18O values if the delta 18O of the water from which it came can be estimated reliably, as is generally thought to be the case for seawater during the Cretaceous. We generate a time series of delta 18O across the K-Pg boundary. We also generated a magnetostratigraphic record for the section, as well as paleobiological data in the same stratigraphic context. Statistical analysis revealed two extinction events, one at the peak of warming from the paleotemperature record (50 meters below the K-Pg boundary), the other simultaneous with the iridium anomaly indicating the asteroid strike. The warming events are also correlated (using magnetostratigraphy) with the timing of Deccan Traps volcanism, which could potentially generate warming via CO2 emission. The evidence is most consistent multiple causes contributing to the end Cretaceous mass extinction over a short geological interval. The plausibility of the Deccan - warming link is explored in Chapter 5, though it is ultimately inconclusive due to the uncertainty in total volumes of CO2 emitted during this event. Chapter 4 (Tobin et al., 2014) performs a similar analysis to that in Chapter 3, but on freshwater mollusks from eastern Montana. Because the paleo-depositional setting was fluvial/lacustrine, traditional delta 18O paleotemperature reconstruction is not a useful tool. Carbonate clumped isotope paleothermometry, while more challenging analytically, avoids this problem, and was used to generate a temperature record across the K-Pg boundary. A cooling trend in summer temperatures was identified in the last ~30 meters of the Cretaceous (though bivalve nutrient stress could plausibly explain the pattern as well). This pattern occurs over the same stratigraphic interval that vertebrate paleontologists have identified biodiversity changes, and could plausibly be related. As with Chapter 3, this study is most consistent with a multiple cause mass extinction.
Author: Michael A. Arthur
Publisher:
ISBN:
Category : Geology, Stratigraphic
Languages : en
Pages : 466
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Book Description
Author: C.P. Marshall
Publisher: Springer Science & Business Media
ISBN: 0412755009
Category : Science
Languages : en
Pages : 677
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Book Description
This is a complete and authoritative reference text on an evolving field. Over 200 international scientists have written over 340 separate topics on different aspects of geochemistry including organics, trace elements, isotopes, high and low temperature geochemistry, and ore deposits, to name just a few.
Author: Philip Ball
Publisher: Oxford University Press
ISBN: 0192840991
Category : Science
Languages : en
Pages : 193
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Book Description
This Very Short Introduction traces the history and cultural impact of the elements on humankind, and examines why people have long sought to identify the substances around them. Looking beyond the Periodic Table, the author takes the reader on an engaging and entertaining tour: from the Greek philosophers who propounded a system with four elements - earth, air, fire, and water - to the modern-day scientists who are able to create their own.
Author: Vivien Gornitz
Publisher: Springer Science & Business Media
ISBN: 1402045514
Category : Science
Languages : en
Pages : 1062
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Book Description
One of Springer’s Major Reference Works, this book gives the reader a truly global perspective. It is the first major reference work in its field. Paleoclimate topics covered in the encyclopedia give the reader the capability to place the observations of recent global warming in the context of longer-term natural climate fluctuations. Significant elements of the encyclopedia include recent developments in paleoclimate modeling, paleo-ocean circulation, as well as the influence of geological processes and biological feedbacks on global climate change. The encyclopedia gives the reader an entry point into the literature on these and many other groundbreaking topics.
Author: John McMurry
Publisher: Prentice Hall
ISBN: 9780321750839
Category : Biochemistry
Languages : en
Pages : 0
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Book Description
Fundamentals of General, Organic, and Biological Chemistry by McMurry, Ballantine, Hoeger, and Peterson provides background in chemistry and biochemistry with a relatable context to ensure students of all disciplines gain an appreciation of chemistry's significance in everyday life. Known for its clarity and concise presentation, this book balances chemical concepts with examples, drawn from students' everyday lives and experiences, to explain the quantitative aspects of chemistry and provide deeper insight into theoretical principles. The Seventh Edition focuses on making connections between General, Organic, and Biological Chemistry through a number of new and updated features -- including all-new Mastering Reactions boxes, Chemistry in Action boxes, new and revised chapter problems that strengthen the ties between major concepts in each chapter, practical applications, and much more. NOTE: this is just the standalone book, if you want the book/access card order the ISBN below: 032175011X / 9780321750112 Fundamentals of General, Organic, and Biological Chemistry Plus MasteringChemistry with eText -- Access Card Package Package consists of: 0321750837 / 9780321750839 Fundamentals of General, Organic, and Biological Chemistry 0321776461 / 9780321776464 MasteringChemistry with Pearson eText -- Valuepack Access Card -- for Fundamentals of General, Organic, and Biological Chemistry
Author: John W. Valley
Publisher: Walter de Gruyter GmbH & Co KG
ISBN: 1501508741
Category : Science
Languages : en
Pages : 676
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Book Description
Volume 43 of Reviews in Mineralogy and Geochemistry follows the 1986 Reviews in Mineralogy (Vol. 16) in approach but reflects significant changes in the field of Stable Isotope Geochemistry. In terms of new technology, new sub-disciplines, and numbers of researchers, the field has changed more in the past decade than in any other since that of its birth. Unlike the 1986 volume, which was restricted to high temperature fields, this book covers a wider range of disciplines. However, it would not be possible to fit a comprehensive review into a single volume. Our goal is to provide state-of-the-art reviews in chosen subjects that have emerged or advanced greatly since 1986. This volume was prepared for Short Course on Stable Isotope Geochemistry presented November 2-4, 2001 in conjunction with the annual meetings of the Geological Society of America in Boston, Massachusetts.
Author: Nivaldo J. Tro
Publisher: Prentice Hall
ISBN: 9780321609205
Category : Science
Languages : en
Pages : 1081
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Book Description
0321609204 / 9780321609205 Chemistry: A Molecular Approach Value Pack (includes Selected Solutions Manual for Chemistry: A Molecular Approach & MasteringChemistry, with myeBook Student Access Kit ) Package consists of: 0131000659 / 9780131000650 Chemistry: A Molecular Approach 0136151167 / 9780136151166 Selected Solutions Manual for Chemistry: A Molecular Approach 0321570138 / 9780321570130 MasteringChemistry™ with Pearson eText Student Access Kit
Author: Yuji Zhao
Publisher: Elsevier
ISBN: 0128228709
Category : Science
Languages : en
Pages : 480
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Book Description
Ultrawide Bandgap Semiconductors, Volume 107 in the Semiconductors and Semimetals series, highlights the latest breakthrough in fundamental science and technology development of ultrawide bandgap (UWBG) semiconductor materials and devices based on gallium oxide, aluminium nitride, boron nitride, and diamond. It includes important topics on the materials growth, characterization, and device applications of UWBG materials, where electronic, photonic, thermal and quantum properties are all thoroughly explored. Contains the latest breakthrough in fundamental science and technology development of ultrawide bandgap (UWBG) semiconductor materials and devices Provides a comprehensive presentation that covers the fundamentals of materials growth and characterization, as well as design and performance characterization of state-of-the-art UWBG materials, structures, and devices Presents an in-depth discussion on electronic, photonic, thermal, and quantum technologies based on UWBG materials
Author: Allan S. Gilbert
Publisher: Springer
ISBN: 9789400748279
Category : Social Science
Languages : en
Pages : 0
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Book Description
Geoarchaeology is the archaeological subfield that focuses on archaeological information retrieval and problem solving utilizing the methods of geological investigation. Archaeological recovery and analysis are already geoarchaeological in the most fundamental sense because buried remains are contained within and removed from an essentially geological context. Yet geoarchaeological research goes beyond this simple relationship and attempts to build collaborative links between specialists in archaeology and the earth sciences to produce new knowledge about past human behavior using the technical information and methods of the geosciences. The principal goals of geoarchaeology lie in understanding the relationships between humans and their environment. These goals include (1) how cultures adjust to their ecosystem through time, (2) what earth science factors were related to the evolutionary emergence of humankind, and (3) which methodological tools involving analysis of sediments and landforms, documentation and explanation of change in buried materials, and measurement of time will allow access to new aspects of the past. This encyclopedia defines terms, introduces problems, describes techniques, and discusses theory and strategy, all in a format designed to make specialized details accessible to the public as well as practitioners. It covers subjects in environmental archaeology, dating, materials analysis, and paleoecology, all of which represent different sources of specialist knowledge that must be shared in order to reconstruct, analyze, and explain the record of the human past. It will not specifically cover sites, civilizations, and ancient cultures, etc., that are better described in other encyclopedias of world archaeology. The Editor Allan S. Gilbert is Professor of Anthropology at Fordham University in the Bronx, New York. He holds a B.A. from Rutgers University, and his M.A., M.Phil., and Ph.D. were earned at Columbia University. His areas of research interest include the Near East (late prehistory and early historic periods) as well as the Middle Atlantic region of the U.S. (historical archaeology). His specializations are in archaeozoology of the Near East and geoarchaeology, especially mineralogy and compositional analysis of pottery and building materials. Publications have covered a range of subjects, including ancient pastoralism, faunal quantification, skeletal microanatomy, brick geochemistry, and two co-edited volumes on the marine geology and geoarchaeology of the Black Sea basin.
