Contributions of Space Geodesy to Geodynamics

Contributions of Space Geodesy to Geodynamics

Author: David E. Smith

Publisher: American Geophysical Union

Published: 1993-01-11

Total Pages: 225

ISBN-13: 0875905242

DOWNLOAD EBOOK

Published by the American Geophysical Union as part of the Geodynamics Series, Volume 24. There are times in the history of a science when the evolving technology has been combined with a singleness of purpose to make possible the next great step. For space geodesy the decade of the 1980s was one of those times. Initiated in the early 1980s, the NASA Crustal Dynamics Project (CDP), a global venture of unprecedented proportions, exploited new technologies to confirm and refine tectonic theories and to advance geodynamics. The highlights of the efforts of scientists and engineers from some 30 countries are contained in the 54 papers collected in three volumes which are dedicated to the memory of Edward A. (Ted) Flinn, the former Chief Scientist of the NASA Geodynamics Program.


Variations in Earth Rotation

Variations in Earth Rotation

Author: Dennis D. McCarthy

Publisher: American Geophysical Union

Published: 1990

Total Pages: 197

ISBN-13: 0875904599

DOWNLOAD EBOOK

Published by the American Geophysical Union as part of the Geophysical Monograph Series, Volume 59. As part of the Nineteenth General Assembly of The International Union of Geodesy and Geophysics Symposium (IUGG) in Vancouver, Canada, Union Symposium U4, "Variations in Earth Rotation" was held August 18-19 1987. The Convenor was Dennis D. McCarthy, U.S. Naval Observatory with P. Paquet, Observatoire Royal de Belgique and M. G. Rochester, St. Johns University serving as co-convernors. In a session on internal structure of the Earth papers dealt with the geophysical effects on Earth rotation parameters. Mantle anelasticity increases the free core nutation (FCN) period by a few days. The period of the FCN and the amplitudes of the main nutation components are sensitive to the ellipticity of the core?]mantle boundary (CMB), and a non-hydrostatic increase of 400m in the flattening of the CMB is a possible explanation of the discrepancies from theory. An alternative suggestion rests on the subseismic description of the nutation spectrum of the stratified liquid core. Evidently new models will have to take into account contributions from the oceans, mantle anelasticity, non-hydrostatic pre-stress, CMB topography and internal core structure.