Ripples in overwater plains of the Yello wriver delta

摘要

The Yellow River flow was often zero in recent years, resulting in forming a lot of abnormal ripples in distribution courses of the overwater plain. According to genesis, all the ripples may be divided into two types: one is water-induced ripple; and the others are wind-induced ripples; and the water-induced ripple may be further divided into current induced and wave-induced ripples; and the water-induced ripple may be further divided into current induced and wave-induced ripples. The most striking feature of the water-induced ripples is small in size, and their widths are usually less than 30 centimeters and their heights not more than 5 centimeters.