【摘要】 本文引进了在地球上表层存在一个章动隔离层的概念,从而建立了一种新的章动模型,求出了运动方程及其解。在天体物理中,中子星的自转与章动问题与此类似,本文也许能供研究此类问题时参考。业已证明,地球的隔离层的性质是“软”的,大约位于地表以下300公里的深度。允许的最小厚度小于1公里,它的粘滞率大约为10¹⁰泊的量级,相当于沥青在15℃时的情况。结果表明,钱德勒摆动的“主峰”是双频,其一是内主体的章动频率,另一是外体本身的章动频率。由于两个频率的拍频作用而产生钱德勒振幅的40年变化周期。两项的振幅互相影响,因而大小相差不大,它们的近似比值是0.7。著名的钱德勒摆动的振幅-周期关系是本文的直接结果。地极运动弧形的急变与1924—1926年左右的180°相变在本质上是一回事,它们是由内、外体的章动频率的相对变化决定的。过去人们从观测中定出的钱德勒摆动Q值在30—60之间,这是一个假Q值,真正的Q值是200左右,和由地震波定出的Q值一致。本文的解还预言,除两个主频率外,其两旁还对称地分布着一系列（一对以上）次要频率。钱德勒摆动的时间常数约为70年,它近似可由地震激发所维持。它的非平滑运动将主要沿平均迹线方向来回运动。更多还原

【Abstract】 In this paper an idea of existing a nutation partition layer (probably a thin layer) in superficial region of the Earth is introduced and therefore a new nutation model is advanced. Equations of polar motion based on it and a more universal solution are given. It is proved that partition layer is in the nature of "soft", locates at depth of about 300 km. Its viscosity is about 1010 poises, similar to that of pitch at 15℃ and allowable minimum thickness is possibly less than 1 km. Conclusions are given as following: "Chandler frequency" is double, of which one is the frequency of nutation of outer part and other is that of inner of the Earth. The period of " 40" years in amplitude is only a beat of these two frequencies. The ratio in amplitude of two terms responding to these frequencies is about10" 125/0." 175=0.7. The empirical relation between the amplitude and period of C.W. is a direct result of this theory. Abrupt change of arc of polar motion and sudden 180° phase change are substantially different parts of same phenomenon. Both of them depond on relative changes of nutation frequencies of inner and outer part. Value of Q(30-60) determined before is a pseudo-Q. Real value of Q for C.W. is nearly 200, which is in agreement to that from seismic waves. It is predicted that in addition to two main frequencies there is a series of secondary frequencies distributing symmetrically about either of these two main C.W. frequencies, that the raw pole should mainly move to and from along or across the mean trace owing to continuous excitations and exchanges of energies of two parts and that the time constant of C. W. is about 70 and it can nearly be maintained by earthquake excitations.更多还原