Terrace dating as an archive of the run-through of the Sanmen Gorges

Abstract

Abstract Analysis of morphological properties in the Sanmen Gorges region of the Yellow River shows that four river terraces have been developed at the entrance to the gorges. Commonly, thick aeolian loess-paleosol sequence was deposited on the terraces, which makes it easy to date the terraces. The dating of paleomagnetic, loess-paleosol sequence matching and thermoluminescence show that terraces T2, T3 and T4 were formed 0.129 Ma, 0.625 Ma and 0.865 Ma ago, respectively. The formation of these terraces in this region indicates that the Yellow River has experienced four intensive downcutting events during the last 0.9 Ma. The Yellow River cut through the Sanmen Gorges and inpoured into the East China Sea no later than 0.865 Ma. ∗ Supported by National Natural Science Foundation of China (Grant Nos. 40471016 and 40401007), Innovation Team Project of National Natural Science Foundation of China (Grant No. 40421101), and the Doctoral Foundation of Ministry of Education, China (Grant No.20030730017)