Fig 1.
(A) The location of the upper Hanjiang River drainage basin between the Yunxi and Yunxian Reaches (the area enclosed in red lines). (B) The location of the TJW profile and other comparison profile sites (after https://www.gscloud.cn) [5,6] within the Yunxian Basin in the reaches of the Hanjiang River valley. (C) Monthly average temperature and precipitation in Yunxi County from 1981 to 2010 (after https://www.nmc.cn). (D) Photo of TJW profile.
Table 1.
Stratigraphic description of the Tuojiawan (TJW) profile in the upper Hangjiang River valley.
Fig 2.
Pedostratigraphy and chronology of the TJW profile [17,22] and other comparison profiles (GXHK, MTS, QFC) [5,6] from the first terrace of the Yunxian Basin in the upper reaches of the Hanjiang River valley.
Fig 3.
Pedostratigraphy, magnetic susceptibility and grain size distribution in the loess-paleosol sequences at the TJW profile in the upper Hanjiang River valley [17].
Fig 4.
Pedostratigraphy, geochemical elements features in the loess-paleosol sequences at the TJW profile in the upper Hanjiang River valley.
Table 2.
Average values of magnetic susceptibility and grain-size distribution in Tuojiawan (TJW) profile in the upper Hanjiang River valley [17].
Table 3.
Average values of geochemical elements in Tuojiawan (TJW) profile in the upper Hanjiang River valley.
Fig 5.
Pedostratigraphic subdivisions, OSL age/depth curve in the loess-paleosol sequences at the TJW profile in the upper Hanjiang River valley [17].
Fig 6.
(A. B, C) The variations of the magnetic susceptibility, Rb/Sr ratio, clay/silt ratio in the TJW profile in the upper Hangjiang River valley.
(D) The stacked paleo-weathering curve of the loess profiles at Weinan, Luochuan, and Yichuan sites [3]. (E) The magnetic susceptibility variation of the Yuanbao profile in Linxia City [7]. (F) The Rb/Sr ratio variation of the Huining profile in Gansu Province [8]. (G). The content of δ18O in Guliya ice core [47].