很高成熟度富有机质页岩的含气性问题

我国南方下古生界页岩的成熟度普遍高于美国工业开发页岩气盆地，对于这套很高成熟度页岩的含气性缺乏研究。在运用激光拉曼光谱分析精确评价该套烃源岩成熟度的基础上，从生气下限、孔隙度演化、纳米孔特征等3方面探讨成熟度对很高成熟度页岩(Ro>2.5%)含气性的影响。研究结果表明：南方下古生界页岩成熟度Ro=2.0%~5.0%，生气下限Ro为3.1%左右，主体已达到生气下限阶段。孔隙结构数据表明，富有机质页岩即使演化到很高成熟度阶段仍保持了一定的孔隙度，其比表面积与纳米孔隙的孔容随成熟度增加（一直到Ro高达3.5%~4.0%）仍然保持增加的趋势。笔者认为，富有机质的页岩既使达到很高的热演化程度仍具有良好的储集性能，所以我国南方下古生界页岩具有很大的页岩气潜力。

Gas content of organic-rich shales with very high maturities

The Lower Paleozoic shales in China south area，which maturities are obviously higher than those of the shales in the producing gas field in the United State，have not been researched on the questions of its gas content.In this study，the maturities of those shales were accurately evaluated through spectral analysis of Raman reflectance，the dead line of gas generation，the evolution of the porosity and nanopore of shales with maturity，as well as the gas content of organic-rich shales with very high maturities were further investigated.The results indicate that the maturities of the Lower Paleozoic shales in China south area Ro rang from 2.0% to 5.0%，and most of them are higher than the dead line of gas generation Ro=3.1%；both of the specific surface area and nanopore volume of organic-rich shales increases with maturity，which allowing them to keep certain porosities even in very high maturities(Ro=3.5%-4.0%).Although being in very high maturity，the Lower Paleozoic shales in China south area still have huge shale gas potential.