MAGNETIC PETROLOGY DATABASE FOR INTERPRETATION LITHOSPHERIC MAGNETIC ANOMALIES

In spite of the numerous efforts to understand the nature of satellite magnetic anomalies, the origin of most of them is still unclear. The interpretation of lithospheric magnetic anomalies is inherently non-unique and complimentary magnetic petrology information is essential for developing global magnetic models. A Global Magnetic Petrology Database (MPDB) is now being compiled at NASA/Goddard Space Flight Center and consists of many thousands of records. The purpose of this database is to provide the geomagnetic community with a comprehensive and user-friendly method of accessing magnetic petrology data via Internet for a more realistic interpretation of satellite (as well as aeromagnetic and ground) magnetic anomalies. MPDB is focused on lower crustal and upper mantle rocks and includes data on mantle xenoliths, serpentinized ultramafic rocks, granulites, iron quartzites and rocks from Archean-Proterozoic metamorphic sequences from all around the world. The definition of crustal magnetic anomalies is improving due to the mini-constellation of three satellites - Oersted, Champ, and SAC-C. Recent lithospheric field models (CM3e, MF1, MF2) reveal magnetic anomalies with better resolution, for example in the areas of Iceland, Polar Urals Mountaines, and Anabar Shield where we have an excellent magnetic petrology records. A prototype of database under development can be found at: http://core2.gsfc.nasa.gov/research/terr_mag/php/MPDB/frames.html