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最新的地震学研究指出 ,地球的内核正在对地球的其余部分作相对旋转。根据数值模拟 ,这一情形可能是由在液态外核中正在作对流运动的流体所保持。另一方面 ,由于地幔中质量分布的不均匀 ,巨大的引力将足以使内核与地幔相匹配。内核的不同旋转会通过在旋转时对自身形状的调整而与这些强大的引力保持一致 ,进而可得出在地球最内部区域内有效粘滞度的一个估计。由推测的旋转率得到的内核粘滞度为小于 10 16 Pa或大于 10 2 0 Pa。之所以有两种结果是因为可能有两种不同的地球动力学方式。这两种方式下的粘滞度估计对于内核中地震各向异性原因的解释具有非常不同的含义。
Recent seismological studies point out that the earth’s core is rotating relative to the rest of the earth. According to numerical simulations, this situation may be due to the fluid in the liquid outer core being held as a convective fluid. On the other hand, due to the uneven mass distribution in the mantle, the huge gravitational force will be sufficient to match the core with the mantle. The different rotations of the kernel are aligned with these strong forces of gravity by adjusting their shape as they rotate, giving an estimate of the effective viscosity in the innermost region of the Earth. The core viscosity derived from the presumed rotation rate is less than 10 16 Pa or more than 10 2 Pa. The reason why there are two kinds of results is because there may be two different types of geodynamics. The viscosity estimation under these two approaches has very different implications for the explanation of the causes of seismic anisotropy in the kernel.