Fingerprinting windblown dust in south-eastern Australian soils by uranium-lead dating of detrital zircon

Abstract

The U-Pb ages of fine-grained zircon separated from 2 dust-dominated soils in the eastern highlands of south-eastern Australia and measured by ion microprobe (SHRIMP) revealed a characteristic age ‘fingerprint’ from which the source of the dust has been determined and by which it will be possible to assess the contribution of dust to other soil profiles. The 2 soils are dominated by zircon 400–600 and 1000–1200 Ma old, derived from Palaeozoic granites and sediments of the Lachlan Fold Belt, but also contain significant components 100–300 Ma old, characteristic of igneous rocks in the New England Fold Belt in northern New South Wales and Queensland. This pattern closely matches that of sediments of the Murray-Darling Basin, especially the Mallee dunefield, suggesting that weathering of rocks in the eastern highlands has contributed large quantities of sediment to the arid and semi-arid inland basins via internally draining rivers of the present and past Murray–Darling River systems, where it has formed a major source of dust subsequently blown eastwards and deposited in the highland soils of eastern Australia.

Pedology and digital soil mapping (DSM)

“…development. A wide range of pedological, geochemical and geophysical analyses have been applied to identify and characterize aeolian dust inputs (Gatehouse et al, 2001). However, most of these contributions often rely on specialized equipment and operator expertise, but do not indicate the spatial distribution of dust deposits across a landscape (Cattle et al, 2003).…”

Role of eolian dust deposits in landscape development and soil degradation in southeastern Australia

“…In areas where dust has been reworked, but not removed from the landscape, these materials may retain some of their original characteristics, such as particle size distributions (Walker et al 1988) or geochemical signatures (Dickson & Scott 1998;Gatehouse et al 2001). Moreover, the accumulation of dust on different landforms has implications for the evolution of soil properties.…”

Provenance of bauxite and clay deposits in the Carboniferous Benxi Formation, Western Henan, China: Constraints from U–Pb geochronology and regional geology

“…Previous studies have investigated the provenance and mineralization processes of karst‐type bauxite through mineralogical and geochemical analyses (Ban et al, 2012; Bogatyrev et al, 2009; Cawood, Wang, Zhao, Xu, & Zi, 2020; Cornell & Schwertmann, 2006; Du, Yu, & Zhang, 2020; Mameli, Mongelli, Oggiano, & Dinelli, 2007; Yu et al, 2020). The successful application of laser ablation–inductively coupled plasma–mass spectrometry (LA–ICP–MS) to the U–Pb isotope dating of detrital zircons has led to progress in provenance and source‐rock analyses of bauxite, both in the NCC (Cai, Wang, Feng, & Zhang, 2015; Cao, Liu, et al, 2018; Cao, Xing, et al, 2018; Liu et al, 2014; Liu et al, 2020; Liu, Qi, et al, 2013; Ma, Lv, & Wu, 2014; Sun, 2019; Wang et al, 2016; Wang, Zhou, Zhao, Ji, & Gao, 2010; Yang, Yang, Wang, & Du, 2014; Zhao & Liu, 2019) and in other bauxite‐rich regions such as South China (Cao et al, 2016; Deng et al, 2010; Du et al, 2020; Gu et al, 2013; Jing, Huang, Fan, Lin, & Jin, 2013; Yu et al, 2014, 2016, 2019, 2020), Australia (Gatehouse et al, 2001), and Italy (Boni, Reddy, Mondillo, Balassone, & Taylor, 2012; Mongelli, Buccione, Gueguen, Langone, & Sinisi, 2016). The sources of bauxite in the northern and southern parts of the NCC are mainly Hercynian magmatic rocks of the Inner Mongolia Uplift and Caledonian magmatic rocks in the North Qinling Orogenic Belt (NQOB), respectively, with considerable compositional differences between the regions.…”

“…source-rock analyses of bauxite, both in the NCC (Cai, Wang, Feng, & Zhang, 2015;Liu et al, 2014;Liu et al, 2020;Liu, Qi, et al, 2013;Ma, Lv, & Wu, 2014;Sun, 2019;Wang et al, 2016;Wang, Zhou, Zhao, Ji, & Gao, 2010;Yang, Yang, Wang, & Du, 2014;Zhao & Liu, 2019) and in other bauxite-rich regions such as South China (Cao et al, 2016;Deng et al, 2010;Du et al, 2020;Gu et al, 2013;Jing, Huang, Fan, Lin, & Jin, 2013;Yu et al, 2014Yu et al, , 2016Yu et al, , 2019Yu et al, , 2020, Australia (Gatehouse et al, 2001), and Italy (Boni, Reddy, Mondillo, Balassone, & Taylor, 2012;Mongelli, Buccione, Gueguen, Langone, & Sinisi, 2016).…”