南极乔治王岛长城站地区火山岩中矿物包裹体的研究

RESEARCH ON THE MINERAL INCLUSIONS FROM BASALTS AND ANDESITES INFILDES PENINSULA, KING GEORGE ISLAND, ANTARCTICA

本文主要讨论了长城站地区第三纪火山岩系的透辉石和斜长石中熔融包裹体的特征、均一温度、挥发组分、玻璃和子矿物的化学成分。透辉石中熔融包裹体均一温度为1070～1170℃,斜长石中熔融包裹体均一温度m≥1100℃。透辉石和斜长石熔融包裹体气泡中组分CO_2为45～93％,H_2S为微量～35％,CH_4为2～20％和CO为2～14％,少量为N_2,O_2,H_2O和H_2。这些组分从火山喷发早期至晚期呈规律性变化。对熔融包裹体的玻璃和子矿物进行成分测定,其子矿物为钙铁橄榄石。

This paper deals with the characteristics, homogenization temperature, volatile constituents and chemical compositions of the glass and daughter minerals of the melt inclusions in diopside and plagioclase from Tertiary volcanic rocks in this area. The homogenization temperature of melt inclusions in the diopside ranges from 1070 to 1170℃. Many melt inclusions in plagioclases have homogenization temperature 1100℃ The composition of the gas bubbles from melt inclusions in diopsides and plagio clases are 45-93% CO2, a few to 35% H2S, 2-20% CH4, 2-14% CO, and small amounts of N2, H2, O2 and H2O. These compositions vary regularly from early to late stages of volcanic eruption. The compositions of glass and daughter minerals in diopside have been analysed and kirschsteteinite is the main daughter mineral.