HR: 0830h
AN: GP31D-0770    [PDF]
TI: Time Structure of the 1991 Magnetic Jerk in the Core-Mantle Boundary Zone by Inverting Global Magnetic Data Supported by Satellite Measurements
AU: Ballani, L
EM: bal@gfz-potsdam.de
AF: GFZ Potsdam, Dept. Geodesy and Remote Sensing, GFZ Potsdam, Dept. Geodesy and Remote Sensing,Telegrafenberg, Potsdam, D-14473 Germany
AU: * Wardinski, I
EM: ingo@gfz-potsdam.de
AF: IPG Paris, IPG Paris 4, place jussieu, cedex 05,, Paris, 75252 France
AU: Stromeyer, D
EM: stro@gfz-potsdam.de
AF: GFZ Potsdam, Dept. Geoengineering, GFZ Potsdam, Dept. Geoengineering, Telegrafenberg, Potsdam, D-14473 Germany
AU: Greiner-Mai, H
EM: grm@gfz-potsdam.de
AF: GFZ Potsdam, Dept. Geodesy and Remote Sensing, GFZ Potsdam, Dept. Geodesy and Remote Sensing,Telegrafenberg, Potsdam, D-14473 Germany
AB: New global magnetic data (Gauss coefficients, monthly values) from 1980 to 2000, fitted to global data up to degree and order 5 only and partly based on high-quality satellite vector data (MAGSAT and CHAMP,OERSTED)) are processed with a recent non-harmonic downward continuation method. It solves the related inverse boundary value problem by approximating the solution (e.g. at the core-mantle boundary) of an equivalent Volterra integral equation with a smoothing minimum-norm solution. In an extended version the magnetic field components in the top layer of the fluid outer core can be determined if fluid velocities of special type are prescribed. Using a weakly conducting mantle and the high conducting fluid in the outer core we investigate the temporal structure of the jerk in 1991 at some stations calculating the dY/dt field component at the core-mantle boundary and underneath in different depths of the fluid outer core assuming an angular velocity there.
DE: 1507 Core processes (8115)
DE: 1560 Time variations--secular and long term
SC: Geomagnetism and Paleomagnetism [GP]
MN: 2003 Fall Meeting