Continents and Oceans
- Renata Dmowska, Harvard University, Cambridge, MA, USA
- James Holton, University of Washington, Seattle, WA, USA
- H. Rossby, University of Rhode Island, Kingston, U.S.A.
- Michael McElhinny, Godwana Consultants, New South Wales, Australia
- Phillip McFadden, Australian Geological Survey Organization, Canberra, Australia
Paleomagnetism is the study of the fossil magnetism in rocks. It has been paramount in determining that the continents have drifted over the surface of the Earth throughout geological time. The fossil magnetism preserved in the ocean floor has demonstrated how continental drift takes place through the process of sea-floor spreading. The methods and techniques used in paleomagnetic studies of continental rocks and of the ocean floor are described and then applied to determining horizontal movements of the Earth's crust over geological time. An up-to-date review of global paleomagnetic data enables 1000 millionyears of Earth history to be summarized in terms of the drift of the major crustal blocks over the surface of the Earth. The first edition of McElhinny's book was heralded as a "classic and definitive text." It thoroughly discussed the theory of geomagnetism, the geologicreversals of the Earth's magnetic field, and the shifting of magnetic poles. In the 25 years since the highly successful first edition of Palaeomagnetism and Plate Tectonics (Cambridge, 1973) the many advances in the concepts, methodology, and insights into paleomagnetism warrant this new treatment. This completely updated and revised edition of Paleomagnetism: Continents and Oceans will be a welcome resource for a broad audience of earth scientists as well as laypeople curious about magnetism, paleogeography, geology, and plate tectonics.Because the book is intended for a wide audience of geologists, geophysicists, and oceanographers, it balances the mathematical and descriptive aspects of each topic.View full description
Undergraduate students, geologists, geophysicists, and earth scientists who are attracted to McElhinny's approachable writing style.
- Published: October 1999
- Imprint: ACADEMIC PRESS
- ISBN: 978-0-12-483355-5
"Overall, there are many impressive things about this book. The concise writing style, objective assessment of data, rigorous numerical analysis, and the shear breadth of material covered all combine to convey an overwhelming sense of authority. However, what pleased me most was the way in which it grew from the nuts and bolts of geomagnetic and paleomagnetic measurements and analyses, to finish with something approaching a unified theory of a billion years of geological history. In the end, I was enthralled!"
--Brad Pillans, Research School of Earth Sciences, Australian National University, Canberra
"McElhinny and McFadden's work follows up the excellent volume, The Magnetic Field of the Earth: Paleomagnetism, the Core, and the Deep Mantle, by Ronald T. Merrill, McElhinny, and McFadden (CH, Feb '97), which necessitates some overlap. It represents an excellent effort by the authors... It is probably the most up-to-date work available paleomagnetism. ...the best book for teaching paleomagnetism. Upper-division undergraduates and up."--M.S. Field, U.S. Environmental Protection Agency;CHOICE MAGAZINE, July/August 2000
"The book focuses more on natural aspects of paleomagnetism and its importance for geology. Some fields, e.g., statistical methods in paleomagnetism and paleomagnetism of the oceanic floor are covered extensively, showing current state-of-the-art to the extent hardly met in other geophysical books. This book also has its own well balanced scientific philosophy which is based on well selected, firm observations."--Pure and Applied Geophysics, 158 (2001)
Table of ContentsGeomagnetism and Paleomagnetism. Geomagnetism. Historical. Main Features of the Geomagnetic Field. Origin of the Main Field. Variations of the Dipole Field with Time. Paleomagnetism. Early Work in Paleomagnetism. Magnetism in Rocks. Geocentric Axial Dipole Hypothesis. Archeomagnetism. Paleointensity Over Geological Times. Paleosecular Variation. Rock Magnetism. Basic Principles of Magnetism. Magnetic Fields, Remanent and Induced Magnetism. Diamagnetism and Paramagnetism. Ferro-, Antiferro- and Ferrimagnetism. Hysteresis. Magnetic Minerals in Rocks. Mineralogy. Titanomagnetites. Titanohematites. Iron Sulfides and Oxyhydroxides. Physical Theory of Rock Magnetism. Magnetic Domains. Theory for Single Domain Grains. Magnetic Viscosity. Critical Size for Single Domain Grains. Thermoremanent Magnetization. Crystallization (or Chemical)Remanent Magnetization. Detrital and Post-Depositional Remanent Magnetization. Viscous and Thermoviscous Remanent Magnetization. Stress Effects and Anisotropy. Methods and Techniques. Sampling and Measurement. Sample Collection in the Field. Sample Measurement. Statistical Methods. Some Statistical Concepts. The Fisher Distribution. Statistical Tests. Calculating Paleomagnetic Poles and Their Errors. Other Statistical Distributions. Field Tests for Stability. Constraining the Age of Magnetization. The Fold Test. Conglomerate Test. Baked Contact Test. Unconformity Test. Consistency and Reversals Tests. Laboratory Methods and Applications. Progressive Stepwise Demagnetization. Presentation of Demagnetization Data. Principal Component Analysis. Analysis of Remagnetization Circles. Identification of Magnetic Minerals and Grain Sizes. Curie Temperatures. Isothermal Remanent Magnetization. The Lowrie-Fuller Test. Hysteresis and Magnetic Grain Sizes. Low-Temperature Measurements. Magnetic Field Reversals. Evidence for Field Reversal. Background and Definition. Self-Reversal in Rocks. Evidence for Field Reversal. The Geomagnetic Polarity Time Scale. Polarity Dating of Lava Flows 06 Ma. Geochronometry of Ocean Sediment Cores. Extending the GPTS to 160 Ma. Magnetostratigraphy. Terminology in Magnetostratigraphy. Methods in Magnetostratigraphy. Quality Criteria for Magnetostratigraphy. Late Creatceous-Eocene: The Gubbio Section. Late Triassic GPTS. Superchrons. Polarity Transitions. Recording Polarity Transitions. Directional Changes. Intensity Changes. Polarity Transition Duration. Geomagnetic Excursions. Analysis of Reversal Sequences. Probability Distributions. Filtering of the Record. Non-Stationarity in Reversal Rate. Polarity Symmetry and Superchrons. Oceanic Paleomagnetism. Marine Magnetic Anomalies. Sea-floor Spreading and Plate Tectonics. Vine-Matthews Crustal Model. Measurement of Marine Magnetic Anomalies. Nature of the Magnetic Anomaly Source. Modeling Marine Magnetic Anomalies. Factors Affecting the Shape of Anomalies. Calculating Magnetic Anomalies. Analysing Older Magnetic Anomalies. The Global Magnetic Anomaly Pattern. Magnetic Anomaly Nomenclature. The Cretaceous and Jurassic Quiet Zones. Paleomagnetic Poles for Oceanic Plates. Skewness of Magnetic Anomalies. Magnetization of Seamounts. Calculating Mean Pole Positions from Oceanic Data. Evolution of Oceanic Plates. The Hotspot Reference Frame. Evolution of the Pacific Plate. Continental Paleomagnetism. Analysing Continental Data. Data Selection and Reliability Criteria. Selecting Data for Paleomagnetic Analysis. Reliability Criteria. The Global Paleomagnetic Database. Testing the Geocentric Axial Dipole Model. The Past 5 Million Years. The Past 3000 Million Years. Global Paleointensity Variations. Paleoclimates and Paleoaltitudes. Apparent Polar Wander. The Concept of Apparent Polar Wander. Determining Apparent Polar Wander Paths. Magnetic Blocking Temperature and Isotopic Ages. Phanerozoic APWPs for the Major Blocks. Selection and Grouping of Data. North America and Europe. Asia. The Gondwana Continents. Paleomagnetism and Plate Tectonics. Plate Motions and Paleomagnetic Poles. Combining Euler and Paleomagnetic Poles. Making Reconstructions From Paleomagnetism. Phanerozoic Supercontinents. Laurussia. Paleo-Asia. Gondwana. Pangea. Paleogeography--300 Ma to Present. Displaced Terranes. Western North America. The East and West Avalon Terranes. Armorica. The Western Mediterranean. South and East Asia. Rodinia and the Precambrian. Rodinia. Paleomagnetism and Rodinia. Earth History--1000 Ma to the Present. Precambrian Cratons. Non Plate Tectonic Hypotheses. True Polar Wander. An Expanding Earth? References. Index.