Chronology of the Holocene loess-paleosol section and its deposition and pedogenesis on the south of Chinese Loess Plateau

• Published in: Journal of geographical sciences Vol. 18; no. 4; pp. 425 - 442
• Main Authors: Jia, Yaofeng, Huang, Chunchang, Pang, Jiangli, Niu, Junjie
• Format: Journal Article
• Language: English
• Published: Heidelberg SP Science in China Press 01.11.2008; Springer Nature B.V
• Subjects: Asia; Bgi / Prodig; China; Earth and Environmental Science; Eolian processes; Geographical Information Systems/Cartography; Geography; Holocene; Loess; Nature Conservation; Paleosols; Physical Geography; Remote Sensing/Photogrammetry; Soils; 全新世古; 沉积序列; 黄土高原南部; Gansu; China; Shaanxi; Loess Plateau; China, People's Rep., Guanzhong Basin; China, People's Rep., Loess Plateau; Chinese Loess Plateau; East Asian monsoon; deposition and pedogenesis; Holocene; loess; Loess; Pedogenesis; Geochronology; Plateau; Palaeo-environment; Stratigraphy; Dating; Palaeosol
• ISSN: 1009-637X; 1861-9568
• DOI: 10.1007/s11442-008-0425-6

Optically stimulated luminescence （OSL） dating for polymlneral fine-grained loess samples, collected in Laoguantai （LGT） section on the south of the Chinese Loess Plateau, was made by application of single-aliquot regenerative-dose （SAR） protocol. A ＇Double-SAW procedure in which aliquots are subjected to both infrared （IR） and blue stimulations was used and two sets of equivalent dose （De） determinations were produced and assumed to relate predominantly to feldspathic and quartz fine grain populations respectively, The OSL ages estimated from IRSL signals are smaller than those estimated from [post-IR] OSL signals due to the anomalous fading of feldspar IR signals, based on fading experiment, The young ages of the samples near ground surface may be originated from the post-depositional disturbance by the intensifying humanity＇s cultivation since 3.0 ka BP in the Guanzhong Basin, south of the Chinese Loess Plateau. Based on OSL dating, as well as field observations and stratigraphic correlation, we determine the chronology of the LGT Ioess-paleosol sequence. In combination with climate proxy records, it is indicated that aeolian loess deposition and pedogenesis underwent polyphase changes during the Holocene, likely to have been driven by shifts in the East Asian monsoon. This suggests that aeolian loess deposition is episodic and highly variable, with contributions from non-aeolian processes such as alluvial deposition found in the area.