准噶尔盆地西北缘夏子街地区油气成藏研究

A Study of Migration and Accumulation of Oil and Gas in Xiazijie Area of Northern-western Parts of Zhungaer Basin

陈建平 查明 王鹏

Chen Jianping Zha Ming Wang Peng

石油大学(华东)资源科学系 山东东营 257061

Department of Resources Science, Petroleum University (East China), Dongying, 257061

利用油气物性及碳同位素等地球化学指标,分析了准噶尔盆地夏子街地区油气成藏特征。研究表明,夏子街地区断裂带与背斜带油气特征具有明显差异:断裂带原油密度在0.73g/cm3~0.86g/cm3之间,油藏气顶气CH4含量平均为87.06%,δ13C1介于-40.96‰~-44.22‰;背斜带原油密度在0.85g/cm3~0.93g/cm3,气顶气CH4平均为73.59%,δ13C1在-46.38‰~-47.83‰之间。这是油气多期成藏的结果,孔隙度、渗透率高的背斜带冲积扇砂体首先捕获了三叠纪末生成的成熟油气,而断裂带聚集了中、晚侏罗世高成熟油气。

There is great difference in petroleum properties and geochemistry between the falut zone and the anticline belt. In fault zone petroleum (oil) density is between 0.73 g/cm3 and 0.86 g/cm3, the average content of CH4 is 87.06%, the value of δ13C1 is between -40.96 ‰ and -44.22 ‰; petroleum density in anticline belt is between 0.85 g/cm3 and 0.95g/cm3, the average content of CH4 is 73.59%, the value of δ13C1 is between -46.38 ‰ and -47.83 ‰. All of this indicated that petroleum accumulated in multi-stage, fluvial sand body is first filled with mature petroleum in anticline belt, and high mature petroleum generated in middle-late Jurassic accumulated in fault zone.