The Characteristics and the Neotectonic Implication of the Hanjiang River Terraces in Yunyang Part" />
<div style="line-height: 150%">The Characteristics and the Neotectonic Implication of the Hanjiang River Terraces in Yunyang Part</div>
Abstract The characteristics of the Hanjiang river terraces in Yunyang part are investigated in the field work. With geological, geomorphological and Quaternary chronological data, we infer that T1-T5 terraces were respectively formed in Holocene-late Pleistocene (about 25 ka B P), the late Pleistocene (about 67 ka B P), the early late Pleistocene-the end of middle Pleistocene (about 128 ka B P), the early middle Pleistocene-the late early Pleistocene (about 1 344 ka B P), no later than early Pleistocene. Horizontal contrast of terraces show activities of Liangyun fault make the vertical differences, indicating uplift between the T3 and T2 terraces from Wufeng, Qingqu and Yunyang basin. We suggest the age of faulting is the end of middle Pleistocene-the early late Pleistocene according to the forming age of the T3 and T2 terraces. The average uplifting rate of Hanjiang terrace in Yunyang part since the early Pleistocene is about 0.052 mm/a, which shows that the uplifting rate and magnitude is weaker than that in Qingling mountain. The main reason may be that Yunyang is located in the southern margin of Qinling mountain but not the center raising area.
