冀南西石门铁矿金云母Rb-Sr等时线年龄及其地质意义  

Phlogopite Rb-Sr Isochron Age from Xishimen Iron Deposit in Southern Hebei Province and its Geological Significance

作　　者：唐玉莹 秦超 白富生 金雅楠 范琳琳 王吉中 张聚全 TANG Yu-ying;QIN Chao;BAI Fu-sheng;JIN Ya-nan;FAN Lin-lin;WANG Ji-zhong;ZHANG Ju-quan(Hebei GEO University,Shijiazhuang 050031,China)

机构地区：[1]河北地质大学,河北石家庄050031

出　　处：《河北地质大学学报》2021年第3期21-26,共6页Journal of Hebei Geo University

基　　金：国家自然科学基金项目(41602028);河北教育厅在读研究生创新能力培养项目(CXZZSS2021121);河北地质大学第十七届学生科研项目(KAY202105)

摘　　要：以冀南西石门铁矿作为研究对象,对蚀变岩中与磁铁矿伴生的金云母进行Rb-Sr等时线测年研究,测年结果显示,该矿床成矿年龄为126.12±0.44 Ma(MSWD=0.75),初始值(^(87)Sr/^(86)Sr)为0.68964±0.00028.结合前人已发表的邯邢地区武安岩体的成岩年龄127 Ma(二长岩)和134 Ma(闪长岩)以及西石门铁矿金云母^(40)Ar-^(39)Ar的成矿年龄133±1.3 Ma,成矿年龄与成岩年龄具有明显的一致性,表明本区矽卡岩型铁矿的成矿与岩体的侵位具有密切的时空联系,与邯邢地区两期成岩活动相对应,可能存在两期成矿作用,并建立两期成矿模式,进一步丰富了“邯邢式铁矿”成矿模式和完善西石门铁矿成因的年代学证据以及找矿依据。Based on Xishimen iron deposit in southern Hebei Province,the Rb-Sr isochron dating of phlogopite associated with magnetite in altered rocks was studied.The dating results show that the ore-forming age of this deposit is 126.12±0.44 Ma(MSWD=0.75)with initial ^(87)Sr/^(86)Sr ratio of 0.68964±0.00028.In combination with previous published 127 Ma(monzonite)and 134 Ma(diorite)of diagenetic ages of Wu'an pluton in Hanxing area,and 133±1.3 Ma of ore-forming age of phlogopite ^(40)Ar-^(39)Ar in Xishimen iron deposit,the ore-forming ages and diagenetic ages show markedly consistent suggest that the mineralization of skarn type deposit in this area and the time and space of emplacement of plutonis is closely related.It is believe that there may be two-periods of mineralization corresponding to the two-periods diagenetic activities in Hanxing area,and construct two-periods mineralization model,further enriching the metallogenic model of Hanxing type iron deposit and complementing the chronological evidence of the genesis and basis for exploration ore bodies of Xishimen iron deposit.

关 键 词：西石门铁矿 金云母 RB-SR等时线年龄 地质意义 

分 类 号：P611[天文地球—矿床学]