This 1994 book examines how reversals of the Earth's magnetic field have played a major role in establishing plate tectonics and a geological time scale.
This reference encompasses the fields of Geomagnetism and Paleomagnetism in a single volume. Both sciences have applications in navigation, in the search for minerals and hydrocarbons, in dating rock sequences, and in unraveling past geologic movements such as plate motions they have contributed to a better understanding of the Earth. The book describes in fine detail the current state of knowledge and provides an up-to-date synthesis of the most basic concepts. It is an indispensable working tool not only for geophysicists and geophysics students but also for geologists, physicists, atmospheric and environmental scientists, and engineers.
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
Consisting of more than 150 articles written by leading experts, this authoritative reference encompasses the entire field of solid-earth geophysics. It describes in detail the state of current knowledge, including advanced instrumentation and techniques, and focuses on important areas of exploration geophysics. It also offers clear and complete coverage of seismology, geodesy, gravimetry, magnetotellurics and related areas in the adjacent disciplines of physics, geology, oceanography and space science.
Much has been written and debated about the various methodologies applied to modern stratigraphic analysis and the ever increasing complexity of terminologies. However, there exist numerous stratigraphic techniques that are reliant upon precise, quantitative, reproducible data, rather than qualitative interpretive stratigraphic methodologies. Such stratigraphic techniques are applied in an entirely pragmatic non-biased manner within the petroleum industry to provide enhanced stratigraphic understanding of petroleum systems. The petroleum industry is a key driver behind the development of new stratigraphic techniques and a major provider of new stratigraphic data, which has resulted in several of these new techniques having been developed as a requirement to the industry. Furthermore, because techniques, such as isotope chemostratigraphy, elemental chemostratigraphy, magnetic susceptibility stratigraphy, numerical biostratigraphy and heavy mineral stratigraphy are based around precise, quantified and reproducible analytical data, they provide an independent means to test the more interpretive stratigraphic methodologies. This volume attempts an overview of stratigraphic methodologies, but largely focuses on data-generative stratigraphic techniques such as chemostratigraphy, magnetic susceptibility stratigraphy, numerical biostratigraphy and heavy mineral stratigraphy. Where appropriate, each paper discusses data generation methods including sample preparation and analytical methods as well outlining data interpretation methods. This is followed by case histories that demonstrate how those data are used to resolve stratigraphic problems, commonly using material derived from petroleum basins around the World.
Magnetic susceptibility (MS) is a tool frequently used by geologists on sediments or rocks to perform correlations and sea-level or climatic reconstructions. Applied measurements are made on unoriented, bulk samples and bulk MS is mostly influenced by the magnetic mineral content of the rock and often interpreted as influenced by detrital inputs. Magnetic data acquisition is fast and straightforward and this allows the high-resolution sampling needed for palaeoclimatic research (e.g. spectral analysis). However, the link with detrital inputs is not always preserved and the impact of diagenesis on the final MS signal can blur primary information. This volume includes contributions dealing with the origin of the magnetic minerals, and the application of MS as a palaeoenvironmental or palaeoclimatic proxy and also as a tool to provide astronomical calibration in order to improve the chronology of selected time intervals.
This book envisages a multi-proxy approach using stable isotopes, geochemical proxies, magnetic susceptibility and associated biotic events for paleoclimatic and paleoenvironmental interpretations of the Mesozoic sedimentary record of India. Mesozoic rocks of India record abnormal sea level rise, greenhouse climate, intensified volcanism, hypoxia in seawater, extensive black shale deposition, and hydrocarbon occurrence. The Mesozoic has also witnessed mass extinction events, evolution of dinosaurs, and breakdown of the supercontinent Pangea and the formation of Gondwana. Although the Mesozoic geology of India has witnessed significant progress in the last century, literature survey reveals a huge gap in knowledge regarding sequence stratigraphy, chemostratigraphy and key geological events. A synthesis of sedimentological, paleontological and chemical data is included to presenting a comprehensive understanding of the Indian Mesozoic record to students, researchers and professionals.