地幔中铀的存在状态及其地球化学含义.pdfVIP

第 12 卷 第 1 期 ( ) Vol . 12 No . 1 地学前缘 中国地质大学 ,北京 ; 北京大学 2005 年 3 月 Eart h Science Frontier s ( China U niver sit y of Geo sciences ,Beij ing ; Peking U niver sit y) Mar . 2005 地幔中铀的存在状态及其地球化学含义 杜乐天 , 　王文广 核工业 北京地质研究院 ,北京 100029 DU L etian ,WAN G Wenguang B eij i ng R esearch I ns t i t ute of Urani um Geology , B eij i ng 100029 , Chi na D U Letian , WANG Wenguang Occurrence states of uranium in the mantle and their geochemical implication. Ea r t h Science F r ont ier s , 2005 , 12( 1) :069078 Abstract : In t hi s p ap er , t he di st ribution , abundance and occurrence st at es of U in mantle xenolit h s are st udied by 235 U fi ssion t rack met hod , and t he movement of mantle fluids i s revealed by mean s of Ut racer , which i s a rep resent ative of incomp atible element s in t he mantle . The result s show t hat t he mantle fluids can p enet rat e in to and concent rat e in t he ult ramicrofi ssures of cryst al s , in t he sp ace between mineral grain s , and in magmatic cell gla sses. The leached (by wat er at room t emp erat ure) mat erial s f rom xenolit h s , which are con sidered a s relics of mantle fluids are very soluble (p H 10) hydrocarbonalkali sub st ances. U sing t he leached result s , we can di stingui sh t he component s of mantle fluids. Key words : mantle uranium ; 235 U fi ssion t rack ; mantle fluids ; incomp atible element s 摘 　要 :用235 U 诱发裂变径迹法对地幔岩捕虏体中铀的分布 、含量及存在状态进行了详细的镜下径迹统计 , 以揭示铀元素在地幔岩中的种种存在状态和分布规律 。在此基础上进一步把铀作为不相容元素群的示踪剂 (t racer) ,指示地幔流体在深部地幔岩中的活动轨迹 。结果表明 ,地幔流体能够渗透到各造岩矿物颗粒间隙、 ( )