Geophysics A Very Short Introduction

1. What is geophysics? -- 2. Planet Earth -- 3. Seismology and the Earth's internal structure -- 4. Siesmicity--the restless Earth -- 5. Gravity and the figure of the Earth -- 6. The Earth's heat -- 7. The Earth's magnetic field -- 8. Afterthoughts

For generations, the ground beneath the feet of our ancestors seemed solid and unchanging. Around 30 years ago, two things happened that were to revolutionize the understanding of our home planet. First, geologists realized that the continents themselves were drifting across the surface of the globe and that oceans were being created and destroyed. Secondly, pictures of the entire planet were returned from space. As the astronomer Fred Hoyle had predicted, this 'let loose an idea as powerful as any in history'. Suddenly, the Earth began to be viewed as a single entity; a dynamic, interacting whole, controlled by complex processes we scarcely understood. It began to seem less solid. As one astronaut put it, 'a blue jewel on black velvet; small, fragile and touchingly alone'. Geologists at last were able to see the whole as well as the detail; the wood as well as the trees. This book brings their account up to date with the latest understanding of the processes that govern our planet. ABOUT THE SERIES: The Very Short Introductions series from Oxford University Press contains hundreds of titles in almost every subject area. These pocket-sized books are the perfect way to get ahead in a new subject quickly. Our expert authors combine facts, analysis, perspective, new ideas, and enthusiasm to make interesting and challenging topics highly readable.

Ranging across the 4.6 billion year history of the planet, geology is the subject that encompasses almost all that we see around us, in one way or another, and also much that we cannot see, beneath our feet, and on other planets. The fruits of geology provide most of the materials that give us shelter, and most of the energy that drives our modern lives. Within the study of geology lie some of the clues to the extraordinary impact our species is going to play out on the planet, in centuries and millennia to come. In this Very Short Introduction Jan Zalasiewicz gives a brief introduction to the fascinating field of geology. Describing how the science developed from its early beginnings, he looks at some of the key discoveries that have transformed it, before delving into its various subfields, such as sedimentology, tectonics, and stratigraphy. Analysing the geological foundations of the Earth, Zalasiewicz explains the interlocking studies of tectonics, geophysics, and igneous and metamorphic petrology and geochemistry; and describes how rocks are dated by radiometric dating. Considering the role and importance of geology in the finding and exploitation of resources (including fracking), he also discusses its place in environmental issues, such as foundations for urban structures and sites for landfill, and in tackling issues associated with climate change. Zalasiewicz concludes by discussing the exciting future and frontiers of the field, such as the exploration of the geology of Mars. ABOUT THE SERIES: The Very Short Introductions series from Oxford University Press contains hundreds of titles in almost every subject area. These pocket-sized books are the perfect way to get ahead in a new subject quickly. Our expert authors combine facts, analysis, perspective, new ideas, and enthusiasm to make interesting and challenging topics highly readable.

Geophysics is the physics of the Earth. Central to the Earth Sciences today, it encompasses areas such as seismology, volcanism, plate tectonics, gravitational anomalies, and the Earth's magnetic field (present and past, as captured in rocks), all of which give clues to both the structure and the working of the Earth. In this Very Short Introduction, William Lowrie describes the internal and external processes that affect the planet, as well as the principles and methods of geophysics used to investigate them. He explains how analysis of the seismic waves produced in earthquakes reveals the internal structure of the Earth. Geophysicists have established that the greatest source of energy powering geological processes is the Earth's internal heat. Deep inside the Earth, the temperature is high enough to produce a fluid outer core of molten iron. It is the motion in this molten iron layer that produces the Earth's magnetic field, which shields the planet against harmful radiation from the Sun and outer space, and thus makes the planet habitable. Lowrie describes how the magnetic field also magnetizes rocks during their formation, leaving a permanent record of the ancient field and its direction that geophysicists have learned to use to interpret past motions of the continents and tectonic plates. From analyses of Earth's deepest interior to measurements made from Earth-orbiting satellites, Lowrie shows how geophysical exploration is vitally important in the search for mineral resources, and emphasizes our need to understand the history of our planet and the processes that govern its continuing evolution. ABOUT THE SERIES: The Very Short Introductions series from Oxford University Press contains hundreds of titles in almost every subject area. These pocket-sized books are the perfect way to get ahead in a new subject quickly. Our expert authors combine facts, analysis, perspective, new ideas, and enthusiasm to make interesting and challenging topics highly readable.

This new edition of the well-established Kearey and Brooks text is fully updated to reflect the important developments in geophysical methods since the production of the previous edition. The broad scope of previous editions is maintained, with even greater clarity of explanations from the revised text and extensively revised figures. Each of the major geophysical methods is treated systematically developing the theory behind the method and detailing the instrumentation, field data acquisition techniques, data processing and interpretation methods. The practical application of each method to such diverse exploration applications as petroleum, groundwater, engineering, environmental and forensic is shown by case histories. The mathematics required in order to understand the text is purposely kept to a minimum, so the book is suitable for courses taken in geophysics by all undergraduate students. It will also be of use to postgraduate students who might wish to include geophysics in their studies and to all professional geologists who wish to discover the breadth of the subject in connection with their own work.

This second edition of Fundamentals of Geophysics has been completely revised and updated, and is the ideal geophysics textbook for undergraduate students of geoscience with an introductory level of knowledge in physics and mathematics. It gives a comprehensive treatment of the fundamental principles of each major branch of geophysics, and presents geophysics within the wider context of plate tectonics, geodynamics and planetary science. Basic principles are explained with the aid of numerous figures and step-by-step mathematical treatments, and important geophysical results are illustrated with examples from the scientific literature. Text-boxes are used for auxiliary explanations and to handle topics of interest for more advanced students. This new edition also includes review questions at the end of each chapter to help assess the reader's understanding of the topics covered and quantitative exercises for more thorough evaluation. Solutions to the exercises and electronic copies of the figures are available at www.cambridge.org/9780521859028.

The proposal that the impact of humanity on the planet has left a distinct footprint, even on the scale of geological time, has recently gained much ground. Global climate change, shifting global cycles of the weather, widespread pollution, radioactive fallout, plastic accumulation, species invasions, the mass extinction of species - these are just some of the many indicators that we will leave a lasting record in rock, the scientific basis for recognizing new time intervals in Earth's history. The Anthropocene, as the proposed new epoch has been named, is regularly in the news. Even with such robust evidence, the proposal to formally recognize our current time as the Anthropocene remains controversial both inside and outside the scholarly world, kindling intense debates. The reason is clear. The Anthropocene represents far more than just another interval of geologic time. Instead, the Anthropocene has emerged as a powerful new narrative, a concept through which age-old questions about the meaning of nature and even the nature of humanity are being revisited and radically revised. This Very Short Introduction explains the science behind the Anthropocene and the many proposals about when to mark its beginning: the nuclear tests of the 1950s? The beginnings of agriculture? The origins of humans as a species? Erle Ellis considers the many ways that the Anthropocene's "evolving paradigm" is reshaping the sciences, stimulating the humanities, and foregrounding the politics of life on a planet transformed by humans. The Anthropocene remains a work in progress. Is this the story of an unprecedented planetary disaster? Or of newfound wisdom and redemption? Ellis offers an insightful discussion of our role in shaping the planet, and how this will influence our future on many fronts. ABOUT THE SERIES: The Very Short Introductions series from Oxford University Press contains hundreds of titles in almost every subject area. These pocket-sized books are the perfect way to get ahead in a new subject quickly. Our expert authors combine facts, analysis, perspective, new ideas, and enthusiasm to make interesting and challenging topics highly readable.