An anisotropic model of the Earth's crust in the Baikal rift zone

Summary. An attempt is made to explain the existence of intracrustal low-velocity layers in rift zones by using an anisotropic model. It is supposed that the anisotropy is due to the preferred orientation of micas and amphiboles in metamorphic rocks forming the upper crust. Analysing the velocity distribution along different directions in anisotropic media the authors conclude that the low-velocity layer must be isotropic (randomly oriented) with an anisotropic lid.