On Gravity Prediction Using Density and Seismic Data

Abstract : After discussing various possibilities for the consideration of density in an integrated geodetic adjustment, a new approach is presented using the physical relationship, namely Newton's attraction integral to construct the necessary auto-and crosscovariances when treating anomalous density as a stationary random process. Isostatic response theory, as developed by Dorman/Lewis as a generalization of Vening Meinesz' isostasy model, is introduced in the derivation and also proposed as deterministic predictor. The empirical relationship between seismic velocities and density as well as gravity is thoroughly investigated. Starting from the wave equation for an inhomogeneous medium, seismological displacements are used forming a stochastic process. For the various numerical investigations geophysical and geodetic/gravimetric data were collected in a local area as well as over the European Alps. Geophysical models of the Mohorovicic discontinuity, the seismic basement, and the depth of the lithosphere as well as a three dimensional P wave velocity model are developed. Numerical tests in gravity prediction are carried out mainly using the attenuated white noise gravity covariance model and quasi-harmonic inversion.