Geoscience Reference
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Chapter 4
Gravimetric Forward and Inverse Modeling
Methods of the Crustal Density Structures
and the Crust-Mantle Interface
Robert Tenzer and Wenjin Chen
Abstract The numerical models and results of the gravimetric interpretation of the
crustal density structures and the Moho geometry are presented. The numerical
scheme applied utilizes the gravimetric forward and inverse modeling derived in
a frequency domain. Methods for a spectral analysis and synthesis of the gravity
and crustal structure models are applied in the gravimetric forward modeling of
the gravity field generated by the major known crustal density structures. The
gravimetric inversion scheme is formulated by means of a linearized Fredholm
integral equation of the first kind. In numerical results we show the gravitational
contributions of crustal density structures and the refined gravity field quantities,
which have a minimum as well as maximum correlation with the Moho geometry.
The resulting gravimetric Moho model is finally presented.
Keywords Crust ￿ Density ￿ Gravity ￿ Isostasy ￿ Moho
4.1
Introduction
Seismic data are primarily used in geophysical studies investigating the Moho
geometry. In the absence or a low coverage of seismic data, gravimetric or combined
gravimetric-seismic methods can be applied. Several different gravimetric methods
of the Moho depth determination have been developed and applied in global
and regional studies. For more details we refer readers to articles, for instance,
by Cadek and Martinec ( 1991 ), Braitenberg and Zadro ( 1999 ), Arabelos et al.
( 2007 ), Sjöberg ( 2009 ), Braitenberg et al. ( 2010 ), Sampietro ( 2011 ), Eshagh et al.
( 2011 ), Sampietro et al. ( 2013 ), Bagherbandi ( 2012 ), Bagherbandi et al. ( 2013 ),
Bagherbandi and Tenzer ( 2013 ), and Tenzer et al. ( 2013 ). The gravimetric methods
are formulated for a chosen isostatic scheme. The Pratt-Hayford isostatic model is
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