Open AccessLate Quaternary loess deposition in the southern Chaiwopu Basin of the northern Chinese Tian Shan foreland and its palaeoclimatic implications
Author(s) -
Lu Honghua,
Xu Yidi,
Niu Ying,
Wang Zhen,
Wang Hui,
Zhao Junxiang,
Zhang Weiguo,
Zheng Xiangmin
Publication year - 2016
Publication title -
boreas
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.95
H-Index - 74
eISSN - 1502-3885
pISSN - 0300-9483
DOI - 10.1111/bor.12152
Subject(s) - geology , foreland basin , loess , aeolian processes , quaternary , sediment , pleistocene , holocene , environmental magnetism , geomorphology , glacial period , geochemistry , structural basin , paleontology
The piedmont aeolian sediment in Central Asia is has been widely used for Quaternary palaeoclimatic reconstructions. Here we present detailed sedimentological and rock magnetic investigations on 188 samples from the ~9.4‐m‐thick Urumqi River section ( URS ) in the southern Chaiwopu Basin of the northern Chinese Tian Shan foreland. Optically stimulated luminescence ( OSL ) dating constrains the time‐span of the URS loess sedimentation from c. 28 to c. 6.8 ka. This chronology implies that the onset of the URS loess sedimentation is approximately synchronous with the Shangwangfeng Glaciation ( MIS 2) in the headwaters of the Urumqi River. Analyses of sediment grain size and rock magnetic parameters indicate that sediment grain‐size composition controls magnetic properties of the URS loess, i.e. the wind intensity model, distinct from the pedogenic model interpreting the variations in magnetic properties of the loess in the Chinese Loess Plateau ( CLP ). Overall, the variations in sediment grain size and magnetic properties throughout the URS indicate that the present study area was dominated by a climate of strengthened wind associated with gradually intensified aridity during the latest Pleistocene. In contrast, the intensity of aridity and coldness during the early Holocene gradually became relatively weakened.