花岗伟晶岩石英流体包裹体中的短链羧酸

Short-chain carboxylates in fluid-inclusions from quartz in granite-pegmatite

用离子色谱法研究了某些花岗伟晶岩中石英流体包裹体浸取液的短链羧酸（甲酸、乙酸、丙酸和草酸）和无机阴离子（氟、氯和硫酸根离子）组成，同时进行了矿物包裹体流体的氢和石英的氧同位素成分测定以及显微计温学研究。结果表明，北京延庆大庄科花岗伟晶岩的石英流体包裹体浸取液中含有少量的甲酸和乙酸。花岗岩演化晚期-伟晶岩阶段的高温水热流体中可以存在短链羧酸。

The compositions of short-chain carboxylates (formate, acetate, propionate and oxalate) and inorganic anions (F-, Cl- and SO2-4) in leachates of fluid inclusions from quartz in some granite-pegmatites were studied using ion chromatography. The compositions of oxygen isotope of quartz and hydrogen isotope of inclusion fluid in the mineral were determined, and microthermometric studies were also carried out. The results show the presence of formate and acetate in a small amount in leachates of fluid inclusions in quartz from the Dazhuangke granite-pegmatite, Yanqing County, Bejing. It is possible that short-chain carboxylates are present in high temperature hydrothermal fluids at the late stage of the granite evolution, the pegmatite stage.