Uranium isotopic constraints on the provenance of dust on the Chinese Loess Plateau

Abstract

Research Article| August 02, 2018 Uranium isotopic constraints on the provenance of dust on the Chinese Loess Plateau Le Li; Le Li 1MOE Key Laboratory of Surficial Geochemistry, Department of Earth and Planetary Sciences, Nanjing University, 163 Xianlindadao, Nanjing 210023, China Search for other works by this author on: GSW Google Scholar Jun Chen; Jun Chen 1MOE Key Laboratory of Surficial Geochemistry, Department of Earth and Planetary Sciences, Nanjing University, 163 Xianlindadao, Nanjing 210023, China Search for other works by this author on: GSW Google Scholar Yang Chen; Yang Chen 1MOE Key Laboratory of Surficial Geochemistry, Department of Earth and Planetary Sciences, Nanjing University, 163 Xianlindadao, Nanjing 210023, China Search for other works by this author on: GSW Google Scholar David William Hedding; David William Hedding 2Department of Geography, University of South Africa, Pioneer Avenue, Florida 1710, South Africa Search for other works by this author on: GSW Google Scholar Tao Li; Tao Li 1MOE Key Laboratory of Surficial Geochemistry, Department of Earth and Planetary Sciences, Nanjing University, 163 Xianlindadao, Nanjing 210023, China Search for other works by this author on: GSW Google Scholar Laifeng Li; Laifeng Li 1MOE Key Laboratory of Surficial Geochemistry, Department of Earth and Planetary Sciences, Nanjing University, 163 Xianlindadao, Nanjing 210023, China Search for other works by this author on: GSW Google Scholar Xiangjun Liu; Xiangjun Liu 3Key Laboratory for Salt Lake Geology and Environment of Qinghai Province, Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining 810008, China Search for other works by this author on: GSW Google Scholar Fangming Zeng; Fangming Zeng 3Key Laboratory for Salt Lake Geology and Environment of Qinghai Province, Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining 810008, China Search for other works by this author on: GSW Google Scholar Weihua Wu; Weihua Wu 1MOE Key Laboratory of Surficial Geochemistry, Department of Earth and Planetary Sciences, Nanjing University, 163 Xianlindadao, Nanjing 210023, China Search for other works by this author on: GSW Google Scholar Liang Zhao; Liang Zhao 1MOE Key Laboratory of Surficial Geochemistry, Department of Earth and Planetary Sciences, Nanjing University, 163 Xianlindadao, Nanjing 210023, China Search for other works by this author on: GSW Google Scholar Gaojun Li Gaojun Li * 1MOE Key Laboratory of Surficial Geochemistry, Department of Earth and Planetary Sciences, Nanjing University, 163 Xianlindadao, Nanjing 210023, China *E-mail: ligaojun@nju.edu.cn Search for other works by this author on: GSW Google Scholar Geology (2018) 46 (9): 747–750. https://doi.org/10.1130/G45130.1 Article history received: 09 May 2018 rev-recd: 28 Jun 2018 accepted: 04 Jul 2018 first online: 02 Aug 2018 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Tools Icon Tools Get Permissions Search Site Citation Le Li, Jun Chen, Yang Chen, David William Hedding, Tao Li, Laifeng Li, Xiangjun Liu, Fangming Zeng, Weihua Wu, Liang Zhao, Gaojun Li; Uranium isotopic constraints on the provenance of dust on the Chinese Loess Plateau. Geology 2018;; 46 (9): 747–750. doi: https://doi.org/10.1130/G45130.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search nav search search input Search input auto suggest search filter All ContentBy SocietyGeology Search Advanced Search Abstract Provenance of the silt on the Chinese Loess Plateau (CLP) is essential for the paleo-environmental interpretation of the thick eolian deposits, but is highly debated. The controversy mainly comes from the multi-interpretation of similar geochemical signatures of potential source areas (PSAs). This work applies the (234U/238U) activity ratio as a new source tracer, because it can distinguish particles with different transporting and recycling histories regardless of petrological origin. The (234U/238U) activity ratio of a fine particle decreases progressively after its production because of the increasing fraction of the 234U precursor ejected out of the particle surface, due to the recoiling effect associated with the α decay of 238U. Distinct spatial patterns of (234U/238U) can be found for the sediments in PSAs and the loess on the CLP. When combined with other constraints, the new findings indicate that the CLP loess can be best explained by the mixing of three end-member dust sources on the northwestern transportation trajectory, namely (1) the Gobi Desert, (2) the Ordos Desert, and (3) the Qilian Mountains. A contribution from the Yellow River is also possible but may not be significant. The identified source partition implies that the eolian silt is mainly produced by processes in the 'High Asia' mountains and, partly, by erosion of the exposed clastic rocks. This new constraint on the production and transportation of eolian dust has great implications for the proxy interpretation of loess related to atmospheric circulation, dust accumulation rate, and chemical indexes. You do not currently have access to this article.