摘要
为了研究禹州煤田煤系泥页岩的矿物组成和页岩气储集层物性,对采自该区石炭二叠系的泥页岩样品进行了X射线衍射分析和有机地球化学实验。结果表明,禹州煤田煤系泥页岩有机碳含量高,有机质类型为Ⅱ型,热演化程度处于成熟—高成熟阶段（平均值为1.62%）;泥页岩矿物组成以石英、黏土矿物为主,平均含量分别为31.9%、63.2%,部分样品中含有少量的长石、菱铁矿、黄铁矿。通过与海相页岩对比,海陆过渡相煤系泥页岩黏土矿物含量为40%~80%,其中高岭石含量高是煤系泥页岩储层的重要特征,平均含量达到29.6%左右。此外,煤系泥页岩的石英脆度和总脆度均比海相页岩要低,其中禹州煤田煤系泥页岩石英脆度为32%,总脆度为36%,与国内其他地区煤系泥页岩脆度相当。表明禹州煤田煤系泥页岩具备较好的页岩气储集层可压裂性。
To study Yuzhou coalfield coal measures argillutite mineral composition and physical property of shale gas reservoir carried out X-ray diffraction analysis and organic geochemical test for Permian argillutite samples from the coalfield. The result has shown that the argillutite has high organic carbon content, organic matter type II, on thermal evolution stages of mature--high maturity （average 1.62%）. Mineral composition is mainly quartz and clay minerals, average contents 31.9% and 63.2% respectively; in part of samples have little feldspar, siderite and pyrite. Comparing with marine facies shale, the transitional facies argillutite contains more clay miner- als with percentage 40%-80%, among them the high content of kaolinite is major feature of coal measures argillutite reservoir, average content about 29.6%. Besides, the total brittleness of quartz in coal measures argillutite is lower than that in marine facies shale. Quarts brittleness of coal measures argillutite in the Yuzhou coalfield is 32%, total brittleness 36%, roughly equivalent to coal measures argil- lutite quartz brittleness in other areas of the country. This shows the argillutite in Yuzhou coalfield coal measures has better shale gas reservoir hydraulic fracability.
出处
《中国煤炭地质》
2016年第10期24-28,共5页
Coal Geology of China
关键词
煤系地层
泥页岩
矿物组成
脆性
禹州煤田
coal measures strata
argillutite
mineral composition
brittleness
Yuzhou coalfield
