A　geochemical　study　of　the　peat　and　soft-brown　coal　from　the　Zhenan　basin,Western　Yunnan,China

Littleisknownaboutthegeochemistryofpeatandsoft-browncoalTheanalyticalchemicaldataoffortyeightsampleshavebeenobtainedforthepeatandsoft-browncoalinthe7henanbasin,westernYunnan.njectionofcontinentaldetritusintotheswampisfavourableforthedegradationofplantremainsandthefor-orationofhumicacid.Theoxidecompositionsoftheashofthepeatandsoft一)rowncoalandtheirdistribution-typeshaveindicatedthatthecontinentaldetritusomefromtwokindsofparentrocks.TheAl2O3andSiO2haveapositivecorrelationwithhumicacid(Hmz)，showingthattheorganicmatterisad-vantageoustotheformationofaluminosilic;atemineral(mainlykaolinite,authigenicorganicclayminerals).TheTiO2enrichmentismainlyrelatedtomineralmaterials.TheGecontentinthepeatandsoft-browncoalrangesfrom0.2-2.6×10-6,anditismainlyboundtothosemineralswithAl2O3andorganicmatters.TheGaContentisfrom2.3-19.1×10-6，anditisassociatedwithmineralsthatareMgO一Baringaluminosilicateminerals.Theuranium(0.3-4.9×10-6)ismainlyboundintheCa-andMg-bearingminerals.Theyarenotenrichedandnotrelatedtoorganicmatter.