随着中国页岩气勘查开发的推进,南方地区上古生界富有机质页岩受到更多的关注.贵州西部地区下石炭统打屋坝组富有机质泥页岩段厚度大、分布范围广,是贵州页岩气勘查重点层位.在页岩气勘查过程中,潜质页岩的有机质丰度、成熟度以及干酪根类型等是评价一个地区页岩气潜力的主要参数.通过对黔西地区打屋坝组富有机质页岩露头样品进行有机碳含量、干酪根类型以及镜质体反射率测试,并结合前人数据,对该页岩有机地化特征进行了描述.黔西地区打屋坝组富有机质页岩有机碳含量普遍大于1.0％,多数分布在1.0％～3.0％范围内;干酪根类型以Ⅱ2型、Ⅲ型为主,少数地区为Ⅱ1型;大部分样品成熟度Ro在1.3％～3.0％之间,处于高成熟阶段和过成熟早期阶段.黔西六盘水水城地区和普安—晴隆地区打屋坝组页岩有机地化条件较好,具有较好的页岩气勘查潜力.%Consideration of the organic-rich shale of the Upper Paleozoic in the southern part of China has been stimulated by the advancement of shale gas exploration and development in China. The organic shale section of the Lower Carboniferous Dawuba Formation in the western part of Guizhou Province, which is widely distributed and thick, is one of the main targets of Guizhou shale gas exploration. In the process of shale gas exploration, the organic matter abundance, maturity and kerogen type of organic-rich shale are the main parameters of shale gas evaluation. In this paper, these three properties were determined on organic shale outcrop samples of the Dawuba Formation and combined with previous data, the organic geochemical characteristics of the Dawuba Formation have been described. The TOC content of organic-rich shale in the Dawuba Formation in the western Guizhou is generally> 1％, and most samples are in the range of 1％-3％. The kerogen in the Dawuba Formation is mainly of type Ⅱ2 and type Ⅲ, and in some parts type Ⅱ1 is present. Ro is generally> 0.6％, mostly distributed in the range of 1.3％-3.0％, which means they are high maturity to over-mature. The regional data show that the organic geochemical properties and the shale gas exploration potential of the Dawuba Formation are better in Liupanshui Shuicheng and Pu'an-Qinglong areas.
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