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Paleomagnetic field analysis occupies a separate place in the variety of studied physical parameters, since it assists us in obtaining specific ‘stamps'of past geomagnetic field configurations. It is well-known that life on Earth and all geological-environmental processes occur in the changing geomagnetic field (the Earth's magnetic field intensity is now decreasing). Geological-geophysical records indicate that hundreds and hundreds of Earth's magnetic field reversals have occurred. Paleomagnetic research has revealed information about ancient (from hundreds to billions years ago) magnetic field changes, which reflects definite geological, archaeological, cosmological and environmental events of that time. Some geodynamic and tectonic information derived from paleomagnetic field analysis cannot be obtained by any other geophysical or geological methods. This book reveals the current understanding of leading scientists studying paleomagnetic on new approaches and results in different regions of the world. Three main issues are presented in the book: a comparison of the Earth's geomagnetic field and the Earth's biota evolution processes over the last 2.5 billion years (Chapter 1); combined paleomagnetic mapping examples of some areas of the Eastern Mediterranean (Chapter 2); various aspects of archaeomagnetic artifact examination, including advanced mathematical approach applications (Chapters 3 and 4); and utilization of geomagnetic data from the past for historical reconstruction of China and Mesoamerica (Chapter 5). The five chapters present results of investigations of scientists from different scientific schools and demonstrate the application of various methods and approaches to analyze ancient and comparatively recent geomagnetic fields. Undoubtedly, these results are interesting both from theoretical and practical points of view. This book is intended for students of corresponding specialties, geologists, geophysicists, archaeologists and environmental scientists. This book can also be of interest to the general public interested in paleomagnetism, archaeology, geology and geophysics.

During the last 30 years the study of the magnetic properties of rocks and minerals has substantially contributed to several fields of science. Perhaps the best known and most significant advances have resulted from the study of palaeomagnetism, which led to quantitative confirmation of continental drift and polar wandering through interpretation of the direction of remanent magnetism observed in rocks of different ages from different continents. Palaeomagnetism has also, through observations of reversals of magnetiz­ ation, ancient secular variation and ancient field intensities provided data relevant to the origin of the geomagnetic field, and other investigations have contributed significantly to large-scale and local geological studies, the dating of archaeological events and artefacts and more recently to lunar and meteoritic studies. Rock and mineral magnetism has proved to be an interesting study in its own right through the complex magnetic properties and interactions observed in the iron-titanium oxide and iron sulphide minerals, as well as contributing to our understanding of remanent magnetism and magnetization processes in rocks. Simultaneous with the development of these studies has been the develop­ ment of instruments and techniques for the wide range of investigations involved.

Palaeomagnetism and archaeomagnetism are fascinating specialized studies because they are applicable to such a wide range of problems in geology, archaeology and geophysics. They can also be undertaken cheaply, when compared with most other geophysical techniques, and, at first sight, simply. In fact, real comprehension of the magnetic processes that have occurred in rocks and other types of material over several thousands or many millions of years is still extremely difficult to assess and measure. On this basis, this book cannot explain all such features, nor can it attempt to cover all the actual and potential applications of the method. All that can be attempted is to give an impression of the ways in which such techniques can be used in a wide variety of fields, and how these techniques are usually applied. The magnetization of rocks is, in fact, one of the earliest of the true sciences, but we are still not in a position to answer many of the problems posed. Consequently some of the examples given of applications are, essentially, state-of-the-art comments, rather than being a review as such. The changing position of the geomagnetic poles with time is still not adequately defined, for example, and some of the more recent conventional views are given, although the emphasis is placed on more subjective, probably more controversial, evaluations.

Methods in Paleomagnetism covers the proceedings of the NATO Advanced Study Institute on Paleomagnetic Methods, held in the Physics Department of the University of Newcastle upon Tyne on April 1-10, 1964. The book focuses on apparatus and techniques used in paleomagnetism and rock magnetism. The selection first offers information on sampling techniques in the field and measurement of natural remanent magnetization. Discussions focus on ballistic and spinner magnetometers; paleomagnetic sampling with a portable coring drill; portable apparatus for collecting small oriented cores; and portable field-sampling equipment. The book also takes a look at procedures to test the stability of magnetization, as well as physical properties of demagnetization; thermal demagnetization by the continuous method; and apparatus for thermal demagnetization by the progressive method. The text ponders on measurement of isotropic and anisotropic susceptibility and magnetic measurements in applied fields. Topics include preliminary account of a refined technique for magnetic susceptibility anisotropy measurement of rocks; errors in anisotropy measurements with the torsion balance; and measurement of the anisotropy of the susceptibility with an astatic magnetometer. The selection is a valuable reference for readers interested in paleomagnetism.

Magnetic Stratigraphy is the most comprehensive book written in the English language on the subject of magnetic polarity stratigraphy and time scales. This volume presents the entirety of the known geomagneticrecord, which now extends back about 300 million years. The book includes the results of current research on sea floor spreading, magnetic stratigraphy of the Pliocene and Pleistocene, and postulations on the Paleozoic. Also included are both historicalbackground and applications of magnetostratigraphy. Individual chapters on correlation are presented, using changes in magnetic properties and secular variation.Key Features• Discusses pioneering work in the use of marine sediments to investigate the Earths magnetic field• Serves as a guide for students wishing to begin studies in magnetostratigraphy• Provides a comprehensive guide to magnetic polarity stratigraphy including up-to-date geomagnetic polarity time scales• Correlates magnetic stratigraphics from marine and non-marine Cenozoic sequences• Details reversal history of the magnetic field for the last 350 million years• Discusses correlation using magnetic dipole intensity changes• Up-to-date correlation of biostratigraphy with magnetic stratigraphy through the late Jurassic