Order and disorder in planetary dynamos : summer study program in geophysical fluid dynamics
MetadataShow full item record
Our principal lecturer, Stephen Childress, can be seen emerging from the "magnetic cottage" he constructed to edify those of us who attended G.F.D. '87. His central theme was the kinematic properties of the "fast" dynamo, one whose growth rate is insensitive to electrical conductivity. These novel studies, and the seminars given by Andrew Soward and others, offer assurance of more mechanistic understanding of evolving magnetic fields in stars and planets. The timely juxtaposition of Childress' lectures on kinematic fast dynamos and the seminars by Bruce Bayly on inertial three-dimensional instabilities of shear flow, may lead soon to a dynamic fast-fast dynamo. Faster than convecting continents, slower than Antarctic bottom water, waves in the Earth's magnetic field move to the west. Geophysicists' knowledge of the underlying process appears to advance at a similar pace. Yet the dynamos of the summer season already have suggested hydromagnetic flows which offer hope both of realizeable laboratory dynamos and more realistic planetary models. Perhaps the pace of testable predictions will quicken?
Showing items related by title, author, creator and subject.
Deep-tow magnetic anomaly study of the Pacific Jurassic Quiet Zone and implications for the geomagnetic polarity reversal timescale and geomagnetic field behavior Tominaga, Masako; Sager, William W.; Tivey, Maurice A.; Lee, Sang-Mook (American Geophysical Union, 2008-07-26)The Jurassic Quiet Zone (JQZ) is a region of low-amplitude magnetic anomalies whose distinctive character may be related to geomagnetic field behavior. We collected deep-tow magnetic profiles in Pigafetta Basin (western ...
Crustal magnetization and the subseafloor structure of the ASHES vent field, Axial Seamount, Juan de Fuca Ridge : implications for the investigation of hydrothermal sites Tontini, F. Caratori; Crone, Timothy J.; de Ronde, Cornel E. J.; Fornari, Daniel J.; Kinsey, James C.; Mittelstaedt, Eric; Tivey, Maurice A. (John Wiley & Sons, 2016-06-24)High-resolution geophysical data have been collected using the Autonomous Underwater Vehicle (AUV) Sentry over the ASHES (Axial Seamount Hydrothermal Emission Study) high-temperature (~348°C) vent field at Axial Seamount, ...
A reduced crustal magnetization zone near the first observed active hydrothermal vent field on the Southwest Indian Ridge Zhu, Jian; Lin, Jian; Chen, Yongshun J.; Tao, Chunhui; German, Christopher R.; Yoerger, Dana R.; Tivey, Maurice A. (American Geophysical Union, 2010-09-21)Inversion of near-bottom magnetic data reveals a well-defined low crustal magnetization zone (LMZ) near a local topographic high (37°47′S, 49°39′E) on the ultraslow-spreading Southwest Indian Ridge (SWIR). The magnetic ...