关键词: 地壳, 上地幔, 弹性, 粘性, 流变模型, 松弛数

Abstract: Based on the Maxwell′ s and Kelvln′ s rheological models,the deformation properties of the different layers in the crust and upper mantle are recongnized using an index called relaxation number,i. e.the ratio of the duration to the relaxation or retardation time.It is indicated that the asthenosphere is always viscous and the deformation properties of the overlying layers are as follows: the mantle lid, the lower crust,and,even, some of the upper crust are viscous in the long geological processes; the upper crust and mantle lid are elastic in the duration of a few decades; and, in general, the upper crust is elastic,while the lower crust and mantle lid are vis cons or anelastic/elasto-viscous in the duration as long as that between the above two situations.In addition, the problems of the flow in the mantle lid, the intraplate long-range transmis sion of driving force, etc. are discussed in terms of the recognition of the deformating properties.

Key words: Crust, Upper mantle, Elastic property, Viscosity, Rheological model, Relaxation number