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Reliability of CHAMP Anomaly ContinuationsCHAMP is recording state-of-the-art magnetic and gravity field observations at altitudes ranging over roughly 300 - 550 km. However, anomaly continuation is severely limited by the non-uniqueness of the process and satellite anomaly errors. Indeed, our numerical anomaly simulations from satellite to airborne altitudes show that effective downward continuations of the CHAMP data are restricted to within approximately 50 km of the observation altitudes while upward continuations can be effective over a somewhat larger altitude range. The great unreliability of downward continuation requires that the satellite geopotential observations must be analyzed at satellite altitudes if the anomaly details are to be exploited most fully. Given current anomaly error levels, joint inversion of satellite and near- surface anomalies is the best approach for implementing satellite geopotential observations for subsurface studies. We demonstrate the power of this approach using a crustal model constrained by joint inversions of near-surface and satellite magnetic and gravity observations for Maude Rise, Antarctica, in the southwestern Indian Ocean. Our modeling suggests that the dominant satellite altitude magnetic anomalies are produced by crustal thickness variations and remanent magnetization of the normal polarity Cretaceous Quiet Zone.
Document ID
20040034236
Acquisition Source
Goddard Space Flight Center
Document Type
Preprint (Draft being sent to journal)
Authors
vonFrese, Ralph R. B.
(Ohio State Univ. Columbus, OH, United States)
Kim, Hyung Rae
(Maryland Univ. Baltimore County Catonsville, MD, United States)
Taylor, Patrick T.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Asgharzadeh, Mohammad F.
(Ohio State Univ. Columbus, OH, United States)
Date Acquired
September 7, 2013
Publication Date
January 1, 2003
Subject Category
Geophysics
Meeting Information
Meeting: 2nd CHAMP Meeting
Location: Potsdam
Country: Germany
Start Date: September 1, 2003
End Date: September 5, 2003
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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