冀南綦村斑状石英二长岩角闪石环带结构及其地质意义  

The Zoning Texture and Its Geological Significance of Amphibole from the Qicun Porphyritic Quartz Monzonite in the Southern Hebei

作　　者：范琳琳 卢静 张聚全 金雅楠 白富生 唐玉莹 秦超 FAN Lin-lin;LU Jing;ZHANG Ju-quan;JIN Ya-nan;BAI Fu-sheng;TANG Yu-ying;QIN Chao(Hebei Provincial Key Laboratory of Strategic Critical Mineral Resources,College of Earth Science,Hebei GEO University,Shijiazhuang 050031,China)

机构地区：[1]河北省战略性关键矿产资源重点实验室,河北地质大学地球科学学院,石家庄050031

出　　处：《矿物岩石地球化学通报》2021年第4期903-913,共11页Bulletin of Mineralogy, Petrology and Geochemistry

基　　金：国家自然科学基金资助项目(41602028);河北地质大学青年项目(QN201708);河北地质大学博士科研启动基金(BQ201609)。

摘　　要：为阐释岩浆两阶段演化过程及其与铁成矿的关系,对邯邢铁矿区斑状石英二长岩中角闪石斑晶环带结构进行了成因矿物学研究。通过角闪石温度计、压力计、氧逸度计和湿度计的计算,发现岩浆在14km深处岩浆房内经过多次岩浆混合过程,其后演化的岩浆侵位到1.9 km的深度。岩浆房的温度为935~964℃,氧逸度为ΔNNO+0.27~ΔNNO+0.85,含水量为4.64%~6.29%,岩浆定位后角闪石结晶的平均温度为719℃,氧逸度为ΔNNO+2.16,含水量为3.94%。通过黑云母温度计和氧逸度计等验证,该计算结果可靠。岩浆较高的含水量和定位后显著增加的氧逸度有利于富铁的流体/熔浆与硅酸盐熔浆的分离,并最终形成邯邢式铁矿。The genetic mineralogical study of the zoning texture of amphibole phenocrysts in the Qicun porphyritic quartz monzonite related to the mineralization of skarn type of iron ore in the Han-Xing area has been carried out in this paper,in order to explain the two-stage evolution process of magma and its possible relationship with iron mineralization.Based on the calculation of thermometer,barometer,oxygen fugacity meter,and hygrometer of amphiboles,it is found that the Qicun porphyritic quartz monzonite could be formed at a depth of 1.9 km by the emplacement of evolved magma which had undergone multiple phases of the magma mixing processes in the magma chamber at depth of 14 km.The calculated temperatures,oxygen fugacities,and water contents of the magma chamber vary from about 935 to 964℃,fromΔNNO+0.27 toΔNNO+0.85,and from 4.64%to 6.29%,respectively.At the time of amphibole crystallization,the emplaced magma had average temperature of 719℃,oxygen fugacity ofΔNNO+2.16,and water content of 3.94 wt.%.The calculated results are confidently verified by using results of the thermometer and oxygen fugacity meter of biotite.The relatively high water content and significantly increased oxygen fugacity of the magma after emplacement are beneficial to the separation of iron-rich ore-forming fluid/melt from silicate melt to finally form the Han-Xing type iron deposit.

关 键 词：角闪石 环带结构 温压计 岩浆混合 

分 类 号：P574.2[天文地球—矿物学]