鄂西利川复向斜南部储层矿物包体与油气生盖运聚关系

Relation between Reservoir Mineral Inclusions and Oil-Gas Generation-Capping, Migration and Accumulation in the Southern Part of the Lichuan Synclinorium, Western Hubei

应用相邻生油层生油条件的好坏和“恢复有机碳全岩热模拟法”计算生烃量与储层包体对比,发现利川复向斜南部石炭系-三叠系储层包体的有机包体富集程度可定性反映生油层的优劣,生油层好者有机包体丰富,反之则差。同样,利用相邻储层有机包体的多寡,结合生油条件的好坏,在一定程度上也可判别相应盖层条件佳否。包体均一温度经压力校正后,可明显看出各储层油气的运移都发生在印支运动后的侏罗纪;油气的初次聚集,各储层并不完全按时代先后为序,有错置现象,但一般在侏罗纪时便已完成了聚集。该区可能有干溪石炭系和黄泥塘二叠系-下三叠统两个印支期古隆起或高带存在。

In light of the merits of the petroleum generation conditions of the adjacent source beds and the correlation of the reservoir mineral inclusions with the hydrocarbon yield calculated with the ' heat simulation method of recovering the whole-rock organic carbon' , it is found that the degree of concentration of organic inclusions in Carboniferous-Triassic reservoir inclusions in the southern part of the Lichuan synclinorium may qualitatively reflect the merits of the source beds: if the source bed is good, organic inclusions are rich, and vice versa. Likewise, whether the conditions of relevant cap rocks are good or not can be judged to a certain degree according to the amount of organic inclusions in adjacent reservoirs combined with the merits of the petroleum generation conditions. The pressure-corrected inclusion homogenization temperatures evidently show that the oil-gas migration in various reservoirs took place in the Jurassic after the Indosinian movement. The primary accumulations of oil-gas for various reservoirs did not all occur according to the age priority, as exemplified by the Maokou and Changxing Formations, but generally petroleum accumulation was completed in Jurassic time. In the study area, there might exist two Indosinian uplifts or high zones, i. e. the Carboniferous Ganxi uplift and the Permian-Lower Triassic Huannitang uplift.