Bimodal grain-size distribution of Chinese loess, and its palaeoclimatic implications

D.G. Sun, J. Bloemendal, D.K. Rea, Z.S. An, J. Vandenberghe, H. Lu, R. Su, T.S. Liu

    Research output: Contribution to JournalArticleAcademicpeer-review

    Abstract

    Grain-size analysis indicates that Chinese loess generally shows a bimodal distribution with a coarse and a fine component. The coarse component, comprising the main part of the loess, has pronounced kurtosis and is well sorted, which is interpreted to be the product of dust storms generated by low-altitude northwesterly winds. Its grain-size reflects the strength of the low-altitude circulation in the dust seasons of the year, and its percentage provides an indicator of the source area aridity and the frequency of dust storms. Conversely, the fine component has a wide grain-size range and is poorly sorted. Sedimentary illustrations based on the grain-size distribution characteristics of bulk samples and of detrital quartz suggest that the fine component probably represents the background dust load of the atmosphere and is mainly transported by high-altitude westerly airstreams. Its grain-size provides an estimate of the westerly air stream intensity. The coarse and fine components of a loess sample can be mathematically separated by fitting a designated mathematical distribution function to the measured grain-size data, and this procedure constitutes an approach for reconstructing the palaeowind system of Northern China. © 2003 Elsevier B.V. All rights reserved.
    Original languageEnglish
    Pages (from-to)325-340
    JournalCatena
    Volume55
    DOIs
    Publication statusPublished - 2004

    Fingerprint

    Dive into the research topics of 'Bimodal grain-size distribution of Chinese loess, and its palaeoclimatic implications'. Together they form a unique fingerprint.

    Cite this