摘要
Inrecentyears,aconsiderableamountofmicroscopicspheruleshavebeenfoundinconcentratesrecoveredfromsomestrataboundgolddepositsoccurringinMiddle-UpperTriassicturbiditeseriesinnorthwesternSichuan.Studyindicatesthatthesespherulesarecosmicdust.ItisthefirsttimethatcosmicdustofextraterrestrialoriginhasbeenfoundinhydrothermalgolddepositsinChina.Thespherulesaresteel-greyincolourandshowmetallicluster.Theirgrainsizeiscommonlylessthan100μm.Accordingtotheircomposition,theybelongtochromium-richironcosmicdust.Thespheruleshavecomplexanddiversemicroscopicstructuresandtextures,i.e.theyshowaverydistinctWidmanstatenstructure.Thevariationofcosmicdustcontentingolddepositsexhibitsapositivecorrelationwiththemineralizationintensitiesandhydrothermalalteration.Sucharelationindicatesthattheoresub-stancesmaytransportnotonlymechanicallybutalsomaychemicallyinhydrothermalsolutions.
出版日期
1995年04月14日(中国Betway体育网页登陆平台首次上网日期,不代表论文的发表时间)