A method of estimating the Moho density contrast with a tentative application of EGM08 and CRUST2.0

• Autorzy: Sjoberg, L. , Bagherbandi, M.
• Języki publikacji: EN

Abstrakty

EN

Based on Vening Meinez-Moritz global inverse isostatic problem, the Moho density contrast is formulated as that of finding a solution of a Fredholm integral equation of the first kind. We present solutions to this equation by combining global models of gravity (EGM08), topography (DTM2006) and seismic crust (CRUST2.0) to a resolution of 2° x 2°. The test computations yielded Moho density contrasts ranging from 81.5 kg/m3 (in Pacific) to 988 kg/m3 (Tibet), with averages of 678 ± 78 and 334 ± 108 kg/m3 for continental and oceanic regions, respectively, and a global average of 448 ± 187 kg/m3. Estimated Moho depths range from 8 to 75 km with continental and oceanic averages of 36.6 ± 5.3 km and 12.9 ± 5.8 km, respectively, and a global average of 21 ± 12.5 km. This article has its emphasis on the new theory, while significant corrections to computational results are expected in a forthcoming study, where the isostatic gravity anomaly will be reduced for several disturbing signals.

Słowa kluczowe

EN

density contrast; isostasy; Moho; topographic compensation

• Czasopismo: Acta Geophysica
• Rocznik: 2011
• Tom: Vol. 59, no. 3
• Strony: 502-525
• Opis fizyczny: Bibliogr. 25 poz.

Twórcy

autor

Sjoberg, L.

autor

Bagherbandi, M.

• Royal Institute of Technology, Division of Geodesy, Stockholm, Sweden,

Bibliografia

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