The shifting continents of the Earth are heading for inevitable collision: 250 million years from now, all the land masses on this planet will come together in a single, gigantic supercontinent which no human is ever likely to see. That future supercontinent will not be the first to form on Earth, nor will it be the last. Each cycle lasts half a billion years, making it the grandest of all the patterns in nature. It is scarcely a century since science first understood how Pangaea, the supercontinent which gave birth to dinosaurs, split apart, but scientists can now look back three-quarters of a billion years into the Earth's almost indecipherable past to reconstruct Pangaea's predecessor, and computer-model the shape of the Earth's far-distant future. Ted Nield's book tells the astounding story of how that science emerged (often in the face of fierce opposition), and how scientists today are using the most modern techniques to draw information out of the oldest rocks on Earth. It also reveals the remarkable human story of the Altantis-seeking visionaries and madmen who have been imagining lost or undiscovered continents for centuries. Ultimately all supercontinents exist only in the human imagination, but understanding the 'Supercontinent Cycle' represents nothing less than finally knowing how our planet works.
The supercontinent-cycle hypothesis attributes planetary-scale episodic tectonic events to an intrinsic self-organizing mode of mantle convection, governed by the buoyancy of continental lithosphere that resists subduction during the closure of old ocean basins, and the consequent reorganization of mantle convection cells leading to the opening of new ocean basins. Characteristic timescales of the cycle are typically 500 to 700 million years. Proposed spatial patterns of cyclicity range from hemispheric (introversion) to antipodal (extroversion), to precisely between those end members (orthoversion). Advances in our understanding can arise from theoretical or numerical modelling, primary data acquisition relevant to continental reconstructions, and spatiotemporal correlations between plate kinematics, geodynamic events and palaeoenvironmental history. The palaeogeographic record of supercontinental tectonics on Earth is still under development. The contributions in this Special Publication provide snapshots in time of these investigations and indicate that Earth’s palaeogeographic record incorporates elements of all three end-member spatial patterns.
Antarctica preserves a rock record that spans three and a half billion years of history and has a remarkable story to tell about the evolution of our Earth, from the hottest crustal rocks yet found in an orogenic system, to the assembly and breakup of Gondwana in the Phanerozoic. This volume highlights our improved understanding of the tectonic events that have shaped Antarctica and how these potentially relate to supercontinent assembly and fragmentation. The internal constitution of the East Antarctic Shield is assessed using information available from the basement geology and from detritus preserved as Mesozoic sediments in the Trans Antarctic Mountains. Accretionary orogenesis along the proto-Pacific margin of Antarctica is examined and the volumes of intracrustal melting compared with juvenile magma additions in these complex orogenic systems assessed. This special volume demonstrates the diversity of approaches required to elucidate and understand crustal evolution and evaluate the supercontinent concept.
To this day, there is a great amount of controversy about where, when and how the so-called supercontinents--Pangea, Godwana, Rodinia, and Columbia--were made and broken. Continents and Supercontinents frames that controversy by giving all the necessary background on how continental crust is formed, modified, and destroyed, and what forces move plates. It also discusses how these processes affect the composition of seawater, climate, and the evolution of life. Rogers and Santosh begin with a survey of plate tectonics, and go on to describe the composition, production, and destruction of continental and oceanic crust, and show that cratons or assemblies of cratons became the first true continents, approximately one billion years after the earliest continental crust evolved. The middle part of the book concentrates on supercontinents, beginning with a discussion of types of orogenic belts, distinguishing those that formed by closure of an ocean basin within the belt and those that formed by intracontinental deformation caused by stresses generated elsewhere. This information permits discrimination between models of supercontinent formation by accretion of numerous small terranes and by reorganization of large old continental blocks. This background leads to a description of the assembly and fragmentation of supercontinents throughout earth history. The record is most difficult to interpret for the oldest supercontinent, Columbia, and also controversial for Rodinia, the next youngest supercontinent. The configurations and pattern of breakup of Gondwana and Pangea are well known, but some aspects of their assembly are unclear. The book also briefly describes the histories of continents after the breakup of Pangea, and discusses how changes in the composition of seawater, climate, and life may have been affected by the sizes and locations of continents and supercontinents.
This volume focuses on Late Mesoproterozoic to early Cambrian events related to Gondwana assembly and break up. The nineteen papers provide a comprehensive review including advanced knowledge and new data from all critical areas of East Gondwana. The recent knowledge of the evolution of East Gondwana, which was regarded as an integral part of the Mesoproterozoic supercontinent Rodinia, is the major theme of the volume, which is reinforced by highlighting this radical and new understanding of the evolution of this region.
Ancient Supercontinents and the Paleogeography of Earth offers a systematic examination of Precambrian cratons and supercontinents. Through detailed maps of drift histories and paleogeography of each continent, this book examines topics related to Earth’s tectonic evolution prior to Pangea, including plate kinematics, orogenic development, and paleoenvironments. Additionally, this book discusses the methodologies used, principally paleomagnetism and tectonostratigraphy, and addresses geophysical topics of mantle dynamics and geodynamo evolution over billions of years. Structured clearly with consistent coverage for Precambrian cratons, this book combines state-of-the-art paleomagnetic and geochronologic data to reconstruct the paleogeography of the Earth in the context of major climatic events such as global glaciations. It is an ideal, up-to>date reference for geoscientists and geographers looking for answers to questions surrounding the tectonic evolution of Earth. Provides robust paleogeographies of Precambrian cratons based on high-quality paleomagnetic and geochronologic data and critically tested by global geological datasets Includes links to updated databases for the Precambrian such as PALEOMAGIA and the Global Paleomagnetic Database (GPMDB) Presents full-color maps of the drift histories of each continent as well as their paleogeographies Discusses key questions regarding continental drift, the supercontinent cycle, and the geomagnetic dipole hypothesis and analyzes palaeography in the context of Earth’s holistic evolution
Earth as an Evolving Planetary System, Second Edition, examines the various subsystems that play a role in the evolution of the Earth. These subsystems include such components as the crust, mantle, core, atmosphere, oceans, and life. The book contains 10 chapters that discuss the structure of the Earth and plate tectonics; the origin and evolution of the crust; the processes that leave tectonic imprints in rocks and modern processes responsible for these imprints; and the structure of the mantle and the core. The book also covers the Earth's atmosphere, hydrosphere, and biosphere; crustal and mantle evolution; the supercontinent cycle; great events in Earth history; and the Earth in comparison to other planets. This book is meant for advanced undergraduate and graduate students in Earth Sciences, with a basic knowledge of geology, biology, chemistry, and physics. It also may serve as a reference tool for specialists in the geologic sciences who want to keep abreast of scientific advances in this field. Slides of all figures in the book can be downloaded on the companion site: http://www.elsevierdirect.com/companion.jsp?ISBN=9780123852274 Kent Condie's corresponding interactive CD, Plate Tectonics and How the Earth Works, can be purchased from Tasa Graphic Arts here: http://www.tasagraphicarts.com/progptearth.html Two new chapters on the Supercontinent Cycle and on Great Events in Earth history New and updated sections on Earth's thermal history, planetary volcanism, planetary crusts, the onset of plate tectonics, changing composition of the oceans and atmosphere, and paleoclimatic regimes Also new in this Second Edition: the lower mantle and the role of the post-perovskite transition, the role of water in the mantle, new tomographic data tracking plume tails into the deep mantle, Euxinia in Proterozoic oceans, The Hadean, A crustal age gap at 2.4-2.2 Ga, and continental growth
"Inspired by a GSA Penrose Conference held in Lander, Wyoming, June 14-18, 2006, this volume discusses the beginning and evolution of plate tectonics on Earth, and gives readers an introduction to some of the uncertainties and controversies related to the evolution of the planet. In the first three sections of the book, which cover isotopic, geochemical, metamorphic, mineralization, and mantle geodynamic constraints, a variety of papers address the question of when "modern-style" plate tectonics began on planet Earth. The next set of papers focuses on the geodynamic or geophysical constraints for the beginning of plate tectonics. The volume's final section synthesizes a broad range of evidence, from planetary analogues and geodynamic modeling, to Earth's preserved geologic record. This work provides an excellent graduate level text summarizing the current state of knowledge and will be of interest to a wide range of earth and planetary scientists."--Publisher's website.
Did you know that millions of years ago the Earth only had one super continent? If you look at a globe today, you’d notice how continents fit into each other like puzzle pieces. But how did the super continent break apart and become seven different continents? Let’s look at the mechanics of the continental drift in this book for fifth graders. Grab a copy today.
Proterozoic Orogens of India: A Critical Window to Gondwana provides a unique opportunity to understand a cross-section of the well-exposed and best-studied part of Earth’s crust and the processes of continental collision. It covers pulses of reworking processes and their impact on magmatism, metamorphism and deformational history of Proterozoic orogens vis-à-vis the supercontinental formation. The details of structural architecture, crustal blocks, shear zone systems, magmatism, metamorphism, geochemical and isotopic signatures, mineralization and tectonic models of all the Proterozoic orogens of India are discussed along with excellent illustrations reflecting the field-based, multi-scale structural and geological data sets. The spatial distribution, geometry, kinematics and transpressional strain of the shear zone systems (mostly suture zones), which are critical to all conceptual models dealing with tectono-metamorphic history of Proterozoic orogens of India, are also covered. The book summarizes and integrates the state-of -the art understanding of the structural architecture, lithological assemblages, petrological, geochemical, geochronological and geophysical aspects of the Proterozoic orogens of India. Includes a much needed state-of-the-art tectonic summary of the voluminous data that has emerged from the Protrozoic orogens of India in the last 2-3 decades Authored by a well-established expert with more than 30 years of experience in the field based, multi-scale structural geological studies of the ancient orogens of India Covers up-to-date reviews and models of Proterozoic orogens developed in the Indian shield over the past 2.5 billion years of Earth history