rocyprisassociatedwiththeseplantassemblageshowthatthisareawastheveldenvironmentwithrarerain,alternationofdroughtandmoistureinlatitudinalclimatezone,whereisfavorablefordevelopmentofmainoilsourcebedincontinentalfaceoilformingbasinofwestQaidamBasin.Keywords:plantfossils,Miocene;Arkin,QaidamBasin(上接第20页)OPPERDEPSOITINGANSUPRoVINCEANDEXPLoRATIoNADVICESYINXian—mingrG哪ProvincialBureauofGeologyandMineralExplorationDeve卸merit,Lanzhou730000,Chios)Abstract:BystudyingthepreviousgeologicalliteraturesandexplorationpracticesinGansuProvince,opperdepositareclassifiedinto8types,andthewholeprovinceisdividedinlo9areasaspre—dictedareaforexplorationofcopperdeposit,and6piecesofadvicesforprospectingsuchdepositshavebeenputforward.Keywords:opperdeposit;predictedtypesofdeposits;predictedareaofprospecting;advices维普资讯