The grain - size distributional coarse and fine rhythms clearly show the well - regulated fluctuation of the climatic changes that result in the changes of river impetus of weihe river . taking the eigenvalue 50 as a boundary , the 75 , 84 and 95 above the eigenvalue have wide flounce range and high sensitivity responding to the sedimentary sequence , which may be called " active eigenvalues " 以md （中位数）也即p50为界，其上的特征值巾75 、 h84 、 q95跳动幅度较大，因其对沉积特征响应的敏感度较高，又可称之为“活性特征值” ；巾5 、 ol6 、 q25跳动幅度较小，对于沉积物粒度特征变更响应的敏感度较低，故可称之为“惰性特征值” 。
