Submitted on June 23, 2006
Accepted on August 23, 2006
Localized Temporal Change of the Earth's Inner Core Boundary
Lianxing Wen 1*
1 Department of Geosciences, State University of New York at Stony Brook, NY 11794, USA.
* To whom correspondence should be addressed.
Lianxing Wen , E-mail: wen{at}earth.geo.sunysb.edu
Compressional waves of an earthquake doublet (two events occurring in South Sandwich on 12/01/1993 and 09/06/2003), recorded at three seismic stations in Russia and Kyrgyzstan and reflected off Earth's inner core boundary, arrived at least from 39 to 70 milliseconds earlier in the 2003 event than in the 1993 event. Such changes indicate that the Earth's inner core radius enlarged locally beneath middle Africa by 0.98 to 1.75 km between these occurring times of the doublet. Changes of inner core radius may be explained by either a differential motion of the inner core assuming that irregularities are present at the inner core boundary and fixed to the inner core, or a rapid growth of the inner core by this amount.
