摘要
安庆夕卡岩型铁铜矿床是长江中下游地区铜、铁成矿带的一个重要组成部分,其成岩成矿特征与典型的夕卡岩矿床有明显差别。本文通过对与成矿密切相关的月山岩体的岩石学和地球化学研究,以及夕卡岩分带特征与夕卡岩矿物学研究,指出岩体具高碱低铁的特征,夕卡岩矿物(石榴子石和透辉石)具富铁的特征,并有明显的逆向分带规律。并据此提出了铁质来源与磁铁矿的成矿作用的新观点,指出Fe质源自于形成岩体的富钠高铁的玄武岩浆;由于AFC作用,使Fe Na分离,形成了富铁的成矿流体。而夕卡岩矿物的逆向分带和富铁夕卡岩矿物的广泛存在则是富铁流体参与夕卡岩成岩作用的结果。
Anqing skarn-type Fe-Cu deposit is an important part of the copper-iron ore belt in middle-lower reaches of the Yangtze River with the great difference in diagenesis and mineralization compared with the classical skarn deposits. By the studies on petrology and geochemistry of Yueshan diorites and skarn mineralogy (garnet and pyroxene) and zonation of minerals, it is identified for Yueshan diorites characterized with high alkali and low Fe and skarn minerals characterized with high Fe and reverse zonation. Based on above facts, a new viewpoint concerned with origin of iron materials and mineralization of magnetite is established. It is indicated that the iron materials may derived from the Na-rich and low-Fe basaltic magma and AFC makes Fe-Na separated and form the Fe-rich mineralized fluid. Moreover, the reverse zonation of skarn minerals and widespread occurrence of Fe-rich skarn minerals are the result of Fe-rich fluid participation in the diagenesis and mineralization of skarn.
出处
《矿物岩石地球化学通报》
CAS
CSCD
2004年第3期219-224,共6页
Bulletin of Mineralogy, Petrology and Geochemistry
基金
中国科学院知识创新工程项目资助(KZCX2-102)
