Analyses of Crustal Motion and Deformation Models in a Curvilinear Coordinate System

Abstract

AbstractWe present rigid block motion model and strain rate model in a geodetic coordinate system as well as those in a spherical coordinate system under the framework of tensor analysis. Both eccentricity and local tangential moving frame are now considered in these models, which are not the case for previous modeling. To explore the effects of these two geometrical characteristics, we investigate differences in parameters such as Euler pole and strain rate tensor by employing these models to invert them. The results show that the eccentricity has minor effects on determining Euler pole and strain rate tensor, indicating that it is reasonable not to consider crustal motion and deformation models in a geodetic coordinate system. On the contrary, the local tangential moving frame plays a big role in changing both of them, meaning that the local frame of velocity being different at each observation site should be taken account of when one builds up strain model in a curvilinear coordinate system. Accordingly, the conventional Savage's crustal deformation model should be refurnished.