陆东—五彩湾地区石炭系烃源岩成熟史差异与油气分布

对陆东—五彩湾地区石炭系烃源岩的成熟度差异性进行了分析,成熟度差异主要与烃源岩埋深、地层沉降隆升等构造运动有关。热演化史研究表明,该区石炭系烃源岩具有3个生烃高峰期,分别为二叠纪末、中侏罗世末和早白垩世末。不同地区烃源岩生烃时刻存在差异,燕山运动中期(早白垩世末)是石炭系烃源岩最终成熟和油气成藏的关键时期;烃源岩的分布控制了陆东—五彩湾地区油气的分布,烃源岩的成熟度控制了油气的组分。

The Difference of Maturity History of Carboniferous Source Rocks and the Oil-Gas Distribution in Ludong-Wucaiwan Area

The difference of maturity of the Carboniferous source rocks in Ludong-Wucaiwan area is analyzed. Such a difference is mainly related to the source rock depth and the subsiding and upstanding of strata in the tectonic movements. The maturity history indicates that there exist three peak stages of hydrocarbon generation for the source rocks in this area, namely, the end of Permian, the end of Middle Jurassic and the end of Early Cretaceous. In different areas the hydrocarbon generation stages are different. The end of Early Cretaceous (the Middle Yanshan movement) is the key period of these source rocks finally reaching mature and the oil-gas accumulation. The distribution of the source rocks controls the distribution of oil and gas in this area, while the maturity of the source rocks controls the component of hydrocarbons.