Application of CRUST 2.0 Global Crustal Model in Isostatic Potential Model Construction

Abstract

Abstract: The determination of disturbing mass is one of the key techniques in the construction of the Earth’s gravity field model (EGM) based on Isostasy. Different distribution of crust density with different depth results in different crustal mass. With spherical layer distribution and Airy compensation models, the application of CRUST 2.0 in the establishment of isostatic potential model was studied here. Calculation models of the isostatic EGM were derived. Then, the contributions of CRUST 2.0 and compensation depth towards the models were discussed. Numerical experiments show that 22.97 km is not the best compensation depth, while 40 km is better than the others, and compensation depths do little help to the ultra-high-degree part of the original model. Besides, the crustal model could modify the ideal model between degree 361 and 1080. Finally, it is hard to figure out which one is better than the other when spherical layer distribution and Airy compensation model have the same compensation depth.

Key words: Isostasy, CRUST 2.0, isostatic potential model, compensation depth, EGM

CLC Number:

P228

References

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