Publication Date:
1996-12-13
Description:
The time dependence of the orientation of Earth's inner core relative to the mantle was determined using a recently discovered 10-degree tilt in the axis of symmetry of the inner core's seismic-velocity anisotropy. Two methods of analyzing travel-time variations for rays traversing the inner core, on the basis of 29 years of data from the International Seismological Centre (1964-1992), reveal that the inner core appears to rotate about 3 degrees per year faster than the mantle. An anomalous variation in inner-core orientation from 1969 to 1973 coincides in time with a sudden change ("jerk") in the geomagnetic field.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Su -- Dziewonski -- Jeanloz -- New York, N.Y. -- Science. 1996 Dec 13;274(5294):1883-7.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉W.-J. Su and A. M. Dziewonski, Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA 02138, USA. R. Jeanloz, Department of Geology and Geophysics, University of California, Berkeley, CA 94720-4767, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/8943196" target="_blank"〉PubMed〈/a〉
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
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Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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