| Han-Xing region is located in the hinterland of the North China Craton and in the south of Taihang Mountains.Mesozoic intrusive rocks are developed and the metallogenic area of the famous Han-Xing type iron ore.In this paper,based on the study of the geological field characteristics,petrography,main elements,trace elements,and three kinds of mineral oxygen fugacity meters in this area,the calculation results of different mineral oxygen fugacity meters in the three rock intrusions are compared,the differences of mineral oxygen fugacity meters are analyzed,and the real oxygen fugacity of magma is evaluated more objectively.The applicability of different mineral oxygen fugacity meters has been discussed,and the relationship between magmatic oxygen fugacity and Han-Xing type iron ore mineralization has been determined from many angles.The oxygen fugacity of magma reflected by zircon,hornblende,and apatite minerals in the Fushan rock body is calculated according to the lithology of the samples.The results of the temperature-oxygen fugacity diagram,box-whisker diagram,and frequency distribution map show that there are differences in the results of zircon oxygen fugacity meter,hornblende,and apatite oxygen fugacity meter,and the oxygen fugacity of zircon is relatively dispersed(?FMQ-5.96 ? ?FMQ + 4.80).However,the results of oxygen fugacity reflected by hornblende and apatite are consistent(?FMQ + 0 ? ?FMQ + 4).In addition,it is also found that the coincidence degree of zircons in acidic rocks such as monzonite is higher than that in hornblende diorite.The major and trace elements of zircon,hornblende,and apatite minerals in Kuangshan intrusions are used to calculate their oxygen fugacity according to lithology.Through three different diagrams of temperature-oxygen fugacity,box beard diagram,and frequency distribution map,it is found that there is little difference in the results of zircon,hornblende,and apatite oxygen fugacity meter.Among them,the ?FMQ value of hornblende ranges from 0.07 to 3.39,with an average of 2.41.The ?FMQ value of apatite varies from 1.04 to 7.27,with an average of 4.77.The oxygen fugacity results of major and trace elements of zircon and apatite,temperature-oxygen fugacity diagram,box diagram,and frequency distribution diagramshow that the oxygen fugacity of Hongshan intrusion is higher as a whole,and the oxygen fugacity reflected by pyroxene syenite is higher than that of gabbro.Compared with different mineral oxygen fugacity meters in different intrusions,it is found that the oxygen fugacity of Fushan intrusion is the lowest and that of Hongshan intrusion is the highest.The oxygen fugacity calculated by apatite minerals is slightly higher than that of hornblende.The projection of the whole rock oxygen fugacity meter shows that the samples of the three rock bodies are projected in the strongly oxidizing area.Through comprehensive research and analysis,the relationship between oxygen fugacity and the mineralization of Han-Xing type iron ore is discussed.The eastern Hongshan intrusion is mainly pyroxene syenite,and there is no iron ore point at present,but copper-gold mineralization is developed,and the calculated oxygen fugacity is the highest;The middle Kuangshan intrusion is mainly monzonitic,the iron ore is the most developed,and the oxygen fugacity is medium;The Fushan intrusion in the west is mainly hornblende diorite with less iron ore and the lowest oxygen fugacity.Diorite,monzodiorite,and hornblende diorite are related to the mineralization of Han-Xing type iron ore,in which monzodiorite is most closely related to mineralization,and the higher oxygen fugacity is,the more favorable for mineralization.Oxygen fugacity is not the only factor controlling the mineralization of Han-Xing type iron ore.Hongshan intrusion has high oxygen fugacity,but pyroxene syenite has little relationship with iron mineralization but has a high correlation with copper and gold mineralization.Therefore,the high oxygen fugacity in Hongshan intrusion is an important sign of searching for copper and gold mineralization. |
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