Comparison of various isostatic marine gravity disturbances

Journal of Earth system science

Lars E Sjöberg2¹  Robert Tenzer1²  Mohammad Bagherbandi2 3¹ 

[1] Division of Geodesy and Geoinformatics, Royal Institute of Technology (KTH), SE-10044 Stockholm, Sweden.$$;Institute of Geodesy and Geophysics, School of Geodesy and Geomatics, Wuhan University, 129 Luoyu Road, Wuhan, China.$$

关键词: Bathymetry;    Bouguer gravity correction;    isostasy;    marine gravity;    gravimetric forward modelling.;   

DOI  :  

学科分类：天文学(综合)

来源: Indian Academy of Sciences

【 摘 要 】

We present and compare four types of the isostatic gravity disturbances compiled at sea level over the world oceans and marginal seas. These isostatic gravity disturbances are computed by applying the Airy–Heiskanen (AH), Pratt–Hayford (PH) and Vening Meinesz–Moritz (VMM) isostatic models. In addition, we compute the complete crust-stripped (CCS) isostatic gravity disturbances which are defined based on a principle of minimizing their spatial correlation with the Moho geometry. We demonstrate that each applied compensation scheme yields a distinctive spatial pattern in the resulting isostatic marine gravity field. The AH isostatic gravity disturbances provide the smoothest gravity field (by means of their standard deviation). The AH and VMM isostatic gravity disturbances have very similar spatial patterns due to the fact that the same isostatic principle is applied in both these definitions expect for assuming a local (in the former) instead of a global (in the latter) compensation mechanism. The PH isostatic gravity disturbances are highly spatially correlated with the ocean-floor relief. The CCS isostatic gravity disturbances reveal a signature of the ocean-floor spreading characterized by an increasing density of the oceanic lithosphere with age.

【 授权许可】

Unknown