Treaties on Geophysics: Core Dynamics, Volume 8, provides a comprehensive review of the current state of understanding of core dynamics. The book begins by analyzing a subject of long-standing and on-going controversy: the gross energetics of the core. It then explains the important elements of dynamo theory; actual fluid motions in the core; the basic physical principles involved in thermochemical convection in the core and the basic equations governing the convection; and turbulence and the small-scale dynamics of the core. This is followed by discussions of the state of knowledge on rotation-induced core flows; the use of first-principles numerical models of self-sustaining fluid dynamos; and the behavior of polarity reversals in numerical dynamo models. The remaining chapters cover the various roles the inner core plays in core dynamics and the geodynamo; experiments that have shaped knowledge about the flows in the core that produce the geodynamo and govern its evolution; and ways the mantle can affect core dynamics, and corresponding ways the core can affect the mantle. - Self-contained volume starts with an overview of the subject then explores each topic with in depth detail - Extensive reference lists and cross references with other volumes to facilitate further research - Full-color figures and tables support the text and aid in understanding - Content suited for both the expert and non-expert

The dependence of inertial oscillation frequency on time since a cylindrical container began rotating from rest is established experimentally for several axially symmetric modes of oscillation. The oscillations were excited by including a sinusoidal perturbation in the rotation speed of the container which served to establish an exchange of fluid between the viscous boundary layers and the interior. The interior is set into oscillation by the boundary layer flow and the resulting axial pressure differences are used to establish the amplitude of the inertial oscillation.

Treatise on Geophysics, Second Edition, is a comprehensive and in-depth study of the physics of the Earth beyond what any geophysics text has provided previously. Thoroughly revised and updated, it provides fundamental and state-of-the-art discussion of all aspects of geophysics. A highlight of the second edition is a new volume on Near Surface Geophysics that discusses the role of geophysics in the exploitation and conservation of natural resources and the assessment of degradation of natural systems by pollution. Additional features include new material in the Planets and Moon, Mantle Dynamics, Core Dynamics, Crustal and Lithosphere Dynamics, Evolution of the Earth, and Geodesy volumes. New material is also presented on the uses of Earth gravity measurements. This title is essential for professionals, researchers, professors, and advanced undergraduate and graduate students in the fields of Geophysics and Earth system science. Comprehensive and detailed coverage of all aspects of geophysics Fundamental and state-of-the-art discussions of all research topics Integration of topics into a coherent whole

An experimental study was made of forced asymmetric oscillations in a liquid-filled, rapidly-rotating, right circular cylinder. Oscillations were forced by causing the cylinder to cone about an axis passing through the center of the cylinder but offset by a small angle from the axis of rotation; the motion is similar to precession of a gyrostat but constrained to fixed frequency and amplitude. The fluctuating pressure response of the liquid in the cylinder was measured using pressure transducers mounted in an end wall. Fluctuating pressure was measured for non-dimensional coning frequencies of .030 to .075, for coning angles of .00018 x .035 radians, and for Reynolds numbers of 5,000 to 500,000. Comparisons were made to existing linear theories of the liquid response. The results agreed with theoretical predictions at the highest Reynolds number, and smallest angles. At the smallest Reynolds number, the data agreed better with the solution of a forced oscillation problem than with the solution of a free oscillation problem. At coning angles as small as .0005, the data showed significant departure from the predictions of linear theory, and at coning angles as small as .0008, the liquid exhibited nonstationary behavior suggestive of a flow instability.

Published by the American Geophysical Union as part of the Geophysical Monograph Series, Volume 72. The study of the Earth's deep interior is the object of a spectacular development due both to new techniques of observation (including very long baseline interferometry and superconducting gravimeters) and to progress in theory spurred by new computing capability. Stimulated by the international SEDI group, founded in 1986, geophysicists from different disciplines—Earth dynamicists, seismologists, geomagneticians, mineral physicists—began to cooperate and integmte more fully one another's work. SEDI meetings favor and promote those close contacts and cooperation. Great efforts will still be needed before all the disciplinary divisions dissolve—if they ever do—but things are clearly improving, as shown by this AGU monograph. We think indeed that this volume is a good, although incomplete, illustration of the situation as described above and that it is a benchmark in the exciting story of the progress in knowledge of the deep interior of our planet.