简介：Sediment-hostedgolddepositsarethemajortypeofgoldresourcesinchina,Concentratedmostlyinthetwo'TriangleRegios',theyaregenerallyhostedinfine-clasticturbidite,hydrothermalchetandmarlrangingfromcambriantoTriassicinage,structurallycontrolledbydomes,anticlinesandsecond-orderedfaults.TheyaresimilartotheCarlin-typegolddepositsinmineralassemblageandgeochemicalmarks,withanelementassociationcloselycomparabletothoseofmodernspringsandsubmarinehydrothermalsediments.Organicmattermayhaveplayedanimportantroleinmineralization.Theoresolutionmaybehydrothermallyalteredmeteoricwaterdevelopediareasoflocalgeothermalanomaly.

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简介：Miningandsmeltingactivitiesarethemaincausesfortheincreasingpollutionofheavymetalsinsoil,waterbodyandstreamsediment.Anenvironmentalgeochemicalinvestiga-tionwascarriedoutinandaroundthePanzhihuaminingandsmeltingareatodeterminetheex-tentofchemicalcontaminationinsoilandsediment.Themainobjectiveofthisstudywastoin-vestigatetheenvironmentalgeochemistryofTi,V,Cr,Mn,Cu,Pb,ZnandAsinsoilandsedimentandtoassessthedegreeofpollutioninthestudyarea.Thedataofheavymetalcon-centrationsrevealthatsoilsandsedimentsintheareahavebeenslightlycontaminated.Geo-chemicalmapsofIgeoofeachheavymetalshowthatthecontaminatedsitesarelocatedinV-Ti-magnetiteslopingandsmelting,ganguesdam.Thepollutionsourcesoftheselectedelementscomemainlyfromdustsresultantfromminingactivitiesandotherthree-waste-effluents.Theareaneedstobemonitoredregularlyfortracemetal,especiallyheavymetalenrichment.

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简介：降雨模拟被进行了在二个耕作惯例学习紫色土的土壤侵蚀过程—轮廓耕作和下坡的耕作。结果证明在二个耕作惯例下面，地表径流能被对数函数公式描述。在降雨的起始的时期，流量的数量与降雨持续时间增加了，20分钟以后，它变得相对不变。土壤侵蚀率的变化过程可以被对数函数公式描述。侵蚀率与降雨持续时间增加了，20分钟以后，它也变得不变。在下坡的耕作状况下面，土壤侵蚀率在轻轻的降雨强度的情况中在轮廓耕作状况下面比那更显著地增加了，并且处于为下坡的耕作和轮廓耕作惯例的侵蚀率没有明显的差别。然而，与增加降雨强度，在下坡的耕作条件下面的土壤侵蚀率能在轮廓耕作条件下面是乘那的超过30。但是这种差别将在大雨的箱子中被归结为某程度。