Journal : Acta Geophysica
Article : Comparison of different gravity field implied density models of the topography

Authors :
Sobotka, J.
University of Wrocław, Institute of Geological Sciences, Department of Structural Geology, Wrocław, Poland,,
Sedighi, M.
K.N. Toosi University of Technology, Faculty of Geodesy and Geomatics Engineering, Tehran, Iran,,
Abstract : Density within the Earth crust varies between 1.0 and 3.0 g/cm³. The Bouguer gravity field measured in south Iran is analyzed using four different regional-residual separation techniques to obtain a residual map of the gravity field suitable for density modeling of topography. A density model of topography with radial and lateral distribution of density is required for an accurate determination of the geoid, e.g., in the Stokes-Helmert approach. The apparent density mapping technique is used to convert the four residual Bouguer anomaly fields into the corresponding four gravity im-plied subsurface density (GRADEN) models. Although all four density models showed good correlation with the geological density (GEODEN) model of the region, the GRADEN models obtained by high-pass filter-ing and GGM high-pass filtering show better numerical correlation with GEODEN model than the other models.

Keywords : Bouguer anomaly, regional residual separation, density model,
Publishing house : Instytut Geofizyki PAN
Publication date : 2009
Number : Vol. 57, no. 2
Page : 257 – 270

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Qute : Sobotka, J. ,Sedighi, M. ,Sedighi, M. , Comparison of different gravity field implied density models of the topography. Acta Geophysica Vol. 57, no. 2/2009