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Examination of thin sections under the microscope is a key part of any study of carbonate sediments, as a companion to field or core logging, and as a necessary precursor to geochemical analysis. This book is designed as a laboratory manual to keep beside the microscope as an aid to identifying grain types and textures in carbonates.
In principle, the distribution of the elements among coexisting phases in equilibrium can be predicted, if one knows the Gibbs free energies of formation and activity coefficients of all chemical species in all phases as functions of temperature, pressure, and compositions of phases. Because this is not always possible, many geochemists attempt to explain and predict the geochemical behavior of various elements by their atomic properties, such as electron configuration, ionization energies, ionic radii, ionic potentials, electric polarizability, crystal lattice energies, hydrolysis constants, solubility products, and electronegativity. This kind of approach has proved to be useful but has also caused confusion when the exact physical meaning of those parameters is ignored. In order to provide a framework for the discussion in the following chapters, these atomic properties and their closely interrelated nature are reviewed in the following sections. For ease of explaining the observed relative abundance of nuclides in the solar nebula in the next chapter, some pertinent nuclear properties are also reviewed here. <...>
A moderately comprehensive reference handbook covering the most important paleontological taxa, terms, concepts, and localities, this book is written primarily for general readers and beginning students in the field. My professional experience lies in technical writing and in teaching literature and history, with a lifelong interest in paleontology inspired by Professor Charles Higgins at UC Davis and by studying the geology collection in UC Berkeley’s beautiful Bacon Hall before it was demolished in 1961. Using the essays of science writers like Loren Eiseley, Stephen Gould, and E.O. Wilson in my composition classes in the 1980s, I made critical thinking and the evolution of life on Earth the center of my teaching. An interesting technical writing project in the early 1990s showed me the lack of a dictionary like this, and I began the groundwork for a good reference work as I directed student research in the history of life in my writing courses. Retiring from teaching in 2014, I have widened my understanding of paleontology with intensive study in the last 5 years. <...>
Vallée (1998) indicated that few exploration and mining companies have explicit and systematic quality-assurance policies, and identified three main approaches: laissez-fair, catch-as-catch-can, and systematic quality control, the latter being very uncommon. In the author’s experience, this situation has not significantly improved in the intervening twelve years.
In 1988, at the request of members of the Society for Mining, Metallurgy, and Exploration (SME), Inc., the President of SME formed Working Party #79, Ore Reserve Definition, with the mission to develop guidelines for the public reporting of exploration information, resources, and reserves. A Subcommittee was appointed by the Working Party to draft these guidelines and submit recommendations to SME. The Subcommittee’s recommendations were published by SME in the April 1991 issue of “Mining Engineering”, and as a document entitled “A Guide for Reporting Exploration Information, Resources, and Reserves” in January 1992. Work continued on an ad-hoc basis until 1996, when Working Party #79 was renamed the SME Committee on Resources and Reserves and became a standing committee. <...>
Foraminifera have an evolutionary history that extends back to the Cambrian, more than 525 million years ago. Since then, they have radiated and evolved. To date, approximately 60,000 fossil and modern species have been validly recognized (LANGER, 2011), and an estimated 10,000 species (including only 40-50 planktonic species) are still living (VICKERMAN, 1992), constituting the most diverse group of shelled microorganisms in modern oceans (SEN GUPTA, 1999). These small-sized organisms, usually 0.1 to 1 mm, may be very abundant, and tens of thousands living specimens per square meter may be found in some environments (WETMORE, 1995). Their mineralized tests (shells) usually get preserved in the sediment after the death of the organism and may constitute a major, sometimes the dominant, part of many modern or fossil sediments (fig. 1). They are easy to collect, and their high-density populations provide an adequate statistical base, even in small volume samples, to perform environmental analyses, making them a powerful tool for environmental assessment. <...>
The Earth is approximately spherical, with a mean radius R = 6370km, a very small flattening (+7/ − 15km), mass 6 × 1024kg, and an average density 5.5g/cm3; the law of gravitational attraction is F = GmMr/r3, where F is the force directed along the separation distance r between two point bodies with mass m and M; and G = 6.67 × 10−8cm3/g · s2 is the gravitation constant.
Oui choice of title for this book deliberately echoes Dseison’s A Hillary ofBritiih Earthquake!, which was published by the Cambridge University Press early in the 1920s. This was one of the first in recent tiroes to make a systematic study of seismic activity in a particular country, which we have tried to emulate for Iran. By calling our study a history we wish also to emphasise the importance оf time in the unfolding of geologic processes, and of investigating the past when attempting to under-&tand the present.
The concept of reciprocal space is over 100 years old and has been of particular use for crystallographers to understand the patterns of spots seen on a detector when x-rays are diffracted by crystals. However, it has a much more general use, especially in the physics of the solid state. In order to understand what it is, how to construct it, and how to make use of it, it is first necessary to start with the so-called real or direct space and then show how reciprocal space is related to it. Direct space describes the objects we see around us, especially regarding crystals, their physical shapes and symmetries, and the arrangements of atoms within: the so-called crystal structure. eciprocal space, on the other hand, deals with the crystals as seen through their diffraction images. Indeed, crystallographers are accustomed to working backward from the diffraction images to the crystal structures, which we call crystal-structure solution. In solid-state physics, one usually works the other way, starting with reciprocal space to explain various solid-state properties, such as thermal and electrical phenomena. <...>
