本文对地幔粘度随温度和压力变化的牛顿流体,求得了控制上涌流动的流体力学方程组在对称轴处的渐近解。从而得到了对称轴上温度、上涌速度和粘度随深度的变化。计算结果对二组有代表性的地幔流变参数给出。结果表明,对称轴上的温度分布几乎与流变参数无关,而上涌速度则强烈依赖流变参数。 In this paper, the asymptotic solution of the hydrodynamics equations governing the upwelling flow at the axis of symmetry is obtained for Newtonian fluids whose viscosity varies with temperature and pressure. Thus the symmetry axis temperature, upwelling velocity and viscosity with the depth of change. The calculation results are given for two sets of representative mantle rheological parameters. The results show that the temperature distribution on the axis of symmetry is almost independent of the rheological parameters, while the upwelling velocity strongly depends on the rheological parameters.