松辽盆地二氧化碳气藏成因及成藏期次分析

通过组分分析、碳同位素及氦同位素分析认为长岭二氧化碳气藏为幔源岩浆成因。文中充分利用包裹体的岩相学特征、均一温度特征、气体组分特征以及碳同位素特征等对长岭断陷CO_2气藏的成藏期次进行了分析,长岭断陷CO_2气藏包裹体温度为160～170℃,均超过该区古地温,推断为热流事件造成的,通过对松辽盆地大地构造环境以及其它分析,综合认为长岭断陷CO_2气藏主要形成于中生代末期至新生代,应为晚期成藏。

Carbon dioxide accumulation stage in the Changling fault depression of the Songliao Basin

According to the component, carbon isotope and helium isotope analysis the Changling's carbon dioxide reservoir came from mantle-derived magma. The paper analyzes the carbon dioxide accumulation period of time and stages in the Changling depression by means of petrography, gas component and carbon isotope of fluid inclusions. Carbon dioxide reservoir is detected in the volcanic rock of the Yingcheng Formation in the Changling fault depression. The temperature of the fluid inclusions is from 160℃ to 170℃, exceeded the palaeogeothermul temperature. So we conclude it is caused with the thermal flow. Based on the tectonic setting and other analysis. We think the carbon dioxide reservoir mainly formed from the end of Mesozoic to Cenozoic. The reservoir is of the late period of accumulation.