HR: 0800h
AN: GP31A-0821 [Abstracts]
TI: Recognizing the longest wavelength lithospheric magnetic signals obscured by overlap with the core
field
AU: * Purucker, M
EM: purucker@geomag.gsfc.nasa.gov
AF: Raytheon ITSS at Geodynamics Br, Goddard Space Flight Center/NASA, Greenbelt, MD 20771
United States
AU: Whaler, K
EM: Kathy.Whaler@ed.ac.uk
AF: School of GeoSciences, University of Edinburgh, West Mains Rd., Edinburgh, EH9 3JW
United Kingdom
AB:
We recognize and characterize two characteristic patterns evident in new maps of the lithospheric field produced using the
CHAMP and Oersted satellites. The boundaries of these patterns define long-wavelength features in the lithospheric field not
previously recognized because they were obscured by overlap with the core field. These boundaries correspond to known crustal
thickness variations.
We characterize the magnetic field patterns in terms of amplitude and shape, and deduce minimum amplitude magnetization
models from the satellite data without specifying magnetization direction. The minimum amplitude trades off with misfit to
the data, but we interpret the pattern and direction of magnetization, which are robust.
DE: 1545 Spatial variations (all harmonics and anomalies)
DE: 1550 Spatial variations attributed to seafloor spreading (3005)
SC: Geomagnetism and Paleomagnetism [GP]
MN: 2004 AGU Fall Meeting