柴达木盆地深部物理参数的反演

通过研究地球对表面载荷的响应来反演确定地球深部的物理参数.采用分为4层的地球模型,各层的介质被看作Maxwell粘弹性体.将柴达木盆地沉降发育过程中积累的沉积物作为随时间变化的载荷加于地表,通过拟合柴达木盆地沉降中心附近地区的沉降过程来研究该地区地壳的厚度及剪切模量、岩石层地幔的粘性及软流层的粘性等物理参数.计算结果表明,该地区地壳的剪切模量不会超过全球平均值的60％,岩石层地幔的粘性系数不大于1.5×10²³Pa·s.通过研究对该地区的深部物理参数得出了新的认识.

AN INVERSION OF PHYSICAL PARAMETERS OF THE EARTH'S INTERIOR IN THE CHAIDUMU BASIN

In this paper physical parameters of the Earth's interior are inversely determined by means of investigating the response of the Earth to surface loading. A four-layered earth model is employed. The media of layers are treated as Maxwell viscoelastic ones. The sediments accumulated during the subsidence development of the Chaidumu Basin are taken to be time-dependent surface loading. The thickness and shear modulus of the crust and the viscosities of the lithosphere mantle and the asthenosphere are investigated by fitting the subsidence process of the Chaidumu Basin. The results show that the shear modulus of the crust in that area is less than 60% of the global average and the viscosity of the lithosphere mantle is less than 1.5 ×10²³Pa.S. The study in this paper gives some new knowledge of the Earth's interior in that area.