Acta Geographica Sinica ›› 2023, Vol. 78 ›› Issue (5): 1213-1232.doi: 10.11821/dlxb202305010

• Surface Process and Land Use • Previous Articles     Next Articles

Drainage connection and terrace formation promoted early hominin occupation in the upper Hanjiang River during the Early-Middle Pleistocene

ZHANG Danfeng1(), WANG Xianyan1(), ZHANG Hanzhi1, LIU Quanyu2, WANG Shejiang3,4, LU Huayu1   

  1. 1. School of Geography and Ocean Sciences, Nanjing University, Nanjing 210023, China
    2. Colleage of Tourism and Environment Resources, Ankang University, Ankang 725000, Shaanxi, China
    3. Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, CAS, Beijing 100044, China
    4. Center for Excellence in Life and Paleoenvironment, CAS, Beijing 100044, China
  • Received:2022-11-21 Revised:2023-03-13 Online:2023-05-25 Published:2023-05-27
  • Contact: WANG Xianyan E-mail:3525901684@qq.com;xianyanwang@nju.edu.cn
  • Supported by:
    National Natural Science Foundation of China(41971005);National Natural Science Foundation of China(42021001);Major Program of National Social Science Foundation of China(19ZDA225)

Abstract:

The Hanjiang River, located between the Qinling and Daba mountains, connects the Hanzhong, Ankang and other intermontane basins where there are numerous paleolithic sites. Here is an ideal area to explore the impacts of geomorphic processes on hominin activities. In this study, based on loess stratigraphy, magnetostratigraphy and detrital zircon U-Pb geochronology, the age of high terraces in the Ankang basin and the time of the drainage connection of the Ankang and Hanzhong basins by the Hanjiang River from west to east was determined. In addition, the possible influence of the evolution of landform and drainage network pattern of the Hanjiang River on the hominin occupation in the southern Qinling Mountains in the context of orbital scale climate change is discussed. The results show that (1) Eight terraces of the Hanjiang River were developed in the Ankang basin, with the sixth forming at ~1.82 Ma; (2) Most of these terraces were formed during the climatic transitions from interglacial to glacial periods, and more terraces were formed under the conditions of the Mid-Pleistocene climate transition (MPT) and the increase of uplift rate of the Qinling Mountains since 1.2 Ma; (3) It was not later than 1.82 Ma when the Hanjiang River connected the Ankang and Hanzhong basins as a result of river capture from east to west. River capture and the resulted connections of intermountain basins provided convenient geomorphological conditions for hominins to migrate into the Qinling and Daba mountains along broad river valleys since ~1.5 Ma, and thereafter fluvial terraces provided beneficial space for hominin activities.

Key words: loess stratigraphy, magnetostratigraphy, zircon U-Pb geochronology, fluvial terrace, drainage network pattern, hominin activities, Ankang basin