The lower Palaeozoic Cambrian Niutitang shale and Silurian Longmaxi shale in the upper Yangtze region are the two most favourable marine shales in south China. Great achievements on shale gas development and production have already been made in the Longmaxi shale in southeastern Sichuan (SES). However, to date, economic shale gas potential has not been proved in northwestern Hunan (NWH), which is still a virgin area for shale gas exploration. Based on detailed outcrop investigation, laboratory testing and numerical simulation, the shale gas potential of Niutitang shale were evaluated in this work. Comparisons were also made through vertically diachroneity contrasting with the Longmaxi shale in the NWH area and horizontally isochronic contrasting with Niutitang shale in the SES area. Through analysing the evolution of the palaeoenvironment and palaeotectonics of the period from Niutitang to Longmaxi, it was found that: (1) the NWH Niutitang shale was developed in the hydrothermal continental shelf paleoenvironment, which provided a favourable environment for shale deposition, so the thicker and higher total organic carbon (TOC) shale was largely developed during this time; (2) By the influence of hydrothermal igneous leaching, the element Si formed quartz, which improved the brittleness of the Niutitang shale; (3) Induced by intense tectonic movement, natural fractures were highly developed in the Niutitang shale, which improved the reservoir connectivity; and (4) By comprehensively considering the TOC, reservoir property, and gas retention conditions, the Niutitang shale is a promising target for shale gas development in this area. The results from this work warrant further exploration work in the Niutitang shale in the NWH area.

长江上游地区的古生界下寒武统牛头塘页岩和志留系龙马溪页岩是华南地区最有利的两个海相页岩。四川省东南部的龙马溪组页岩气在开发和生产方面已取得了巨大成就。然而，迄今为止，尚未在湘西北（NWH）证实页岩气具有经济潜力，该地区仍是页岩气勘探的原始地区。在详细的露头调查，实验室测试和数值模拟的基础上，对牛头塘页岩的页岩气潜力进行了评估。还通过在NWH地区与龙马溪组页岩进行垂直钻探对比和在SES地区与牛头塘页岩进行水平等时对比进行了比较。通过对牛塘塘至龙马溪期古环境和古构造的演化分析，发现：（1）牛牛塘西北页岩发育于热液陆架古环境，为页岩沉积提供了有利的环境，因此较厚。在此期间，主要开发出了更高的总有机碳（TOC）页岩；（2）Si元素受热液火成岩浸出的影响形成石英，提高了牛头塘页岩的脆性。（3）在强烈的构造运动的诱导下，牛塘塘页岩自然发育裂缝，改善了储集层的连通性；（4）通过综合考虑总有机碳，储层性质和储气条件，牛塘塘页岩是该地区页岩气开发的有希望的目标。这项工作的结果值得在西北地区牛头塘页岩进行进一步的勘探工作。