The Yellow River's terraces in its source region are mainly accumulation terraces with low height and flat surfaces. First-level terraces are found from the source to Gyaring Lake, second-level from Ngoring Lake to Yellow River Township, and third-level from Yellow River Township to eastern Jigzhi County. These terraces were formed from late Middle Pleistocene to Holocene, with T1 terrace forming about 10,000 years ago, T2 from 58,000 to 19,000 years ago, and T3 from 161,000 to 25,000 years ago. The Yellow River in the source region likely formed in the late Late Pleistocene.