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grl50426-sup-0001-Fs1a.jpgJPEG image55KSatellite view of typical landscape of the study area (21º 27’ N, 110º 26’ E, elevation 33m) showing polygonal landscape patterns.
grl50426-sup-0002-Fs1b.JPGJPEG image1068KField photo showing landscape as a series of interlocking low hills with tree crops on upper slopes and paddy cultivation in valley bottoms.
grl50426-sup-0003-fs2.pdfPDF document369KOSL decay curves and dose response curves
grl50426-sup-0004-Fs3a.jpgJPEG image165KParticle sizes (cumulative percentage) of three samples from Hainan island from most easterly (178) to most westerly (197), showing fining over a distance of 150 km. from east to west. The most easterly sample (178) at approximately 3 km. from the coast is sand, comparable to the well researched ‘Old Red Sands of Guangdong’ (Zheng and Wang, 1998). Samples were taken from road cuts, approximately 1.5m below the surface and grain size analysis was performed by dry sieving and wet hydrometer method. For location see Figure 1, and for sample characteristics see Supplementary table 1. The Hainan samples are generally redder and appear more weathered than those farther north.
grl50426-sup-0005-Fs3b.JPGJPEG image1350KLoess section at Chengmai, Hainan Island. This site (137 on Figure 1) comprises red (2.5YR6/6) fine sandy silt. The foreground is not bedrock, but compacted loess, and the exposed section represents the summit of a loess hill approximately 30m high. Photo taken after rain, explaining darker tone of lower section.
grl50426-sup-0006-Ts01.docxWord 2007 document18KSoil sample characteristics (particle size classes in %)
grl50426-sup-0007-ts02.docxWord 2007 document14KConcentrations of radioisotopes and water content
grl50426-sup-0008-README.txtplain text document2KSupporting Information

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