HR: 15:50h
AN: GP24A-02 INVITED     [Abstracts]
TI: An overview of new methods for deriving and interpreting satellite magnetic anomaly maps
AU: * Maus, S
EM: stefan.maus@noaa.gov
AF: National Geophysical Data Center and University of Colorado at Boulder, NOAA E/GC1 325 Broadway, Boulder, CO 80305 United States
AU: Hemant, K
EM: hemant@gfz-potsdam.de
AF: GeoForschungsZentrum, Telegrafenberg, Potsdam, 14473 Germany
AB: Since July 2000, the low orbiting CHAMP satellite is measuring the magnetic field in unprecedented resolution and accuracy. After 2009, the Swarm constellation of satellites will provide even more accurate measurements, including the east-west vector gradients of the field. Even with the exceptional data quality, compiling high resolution magnetic anomaly maps remains a formidable task. Due to attenuation with altitude, crustal features of scale lengths smaller than the satellite altitude are very weak and easily masked by the signatures of magnetospheric, ionospheric and ocean flow induced electric currents. Particularly challenging is the derivation of global anomaly maps which are not only valid at satellite altitude, but can be downward continued to the surface of the Earth and combined with marine and aeromagnetic compilations. Global and regional interpretation of satellite magnetic anomalies is also making considerable progress. Geographical Information System (GIS) methods are used to effectively combine geological, tectonic, petrological and seismic information of the crust. The merit of including the rather sparse heat flow data is currently being investigated. GIS models can be used to predict magnetic anomalies and compare them with the observations in order to test different hypotheses on the structure and composition of the crust. Apart from this forward modeling approach, new inverse methods have been developed to map the vertically integrated magnetization of the crust and to determine the thickness of the magnetized layer.
UR: http://www.ngdc.noaa.gov/seg/geomag/geomag.shtml
DE: 0903 Computational methods, potential fields
DE: 0925 Magnetic and electrical methods
DE: 1517 Magnetic anomaly modeling
DE: 1532 Reference fields (regional, global)
DE: 1545 Spatial variations (all harmonics and anomalies)
SC: Geomagnetism and Paleomagnetism [GP]
MN: 2005 Joint Assembly