Gravity changes and deformation due to a magmatic intrusion in a two- layered crustal model

Abstract

The paper develops and extends theoretical and computational methods for the calculation of the deformation, gravity and potential change due to a point source of magma injection into a multilayered, elastic-gravitational earth model. In the calculations, which are based upon the method outlined by Rundle, two distinct layers overlying a half-space may be incorporated. The source can be located in either of the layers or the half-space. The method is quite general, and can be readily adapted to calculations in which stresses in either the layers or the half-space relax by viscoelastic flow. The results obtained indicate that the use of homogeneous half-space to represent the Earth may in some cases by too simple a model and that variations in elastic moduli have a more significant effect than variation in reference density on both the surface displacements and gravity changes. -from Authors