宁武盆地太原组海陆过渡相页岩微观孔隙特征

发布时间：2018-07-08 17:45

  本文选题：海陆过渡相 + 页岩孔隙　； 参考：《中国矿业》2017年02期

【摘要】：以宁武盆地太原组海陆过渡相页岩为研究对象,借助扫描电镜观察了页岩微观孔隙特征,采用核磁共振(NMR)技术和低温氮吸附实验相结合的方法深入研究了孔隙结构。结果表明:宁武盆地太原组海陆过渡相页岩主要发育有机质孔、矿物晶间孔、铸模孔和微裂隙四类孔隙;页岩样品T2谱特征相似,形态上表现为双峰,峰值分别介于0.8~1ms,20~50ms之间,根据左峰高低可划分为高峰T2谱和低峰T2谱两类,高峰T2谱样品成熟度偏低,有机碳含量较高,低峰T2谱样品成熟度高,有机碳含量低,表明有机碳含量和成熟度可能会影响孔隙的发育;低温氮吸附实验结果显示样品具有Ⅳ型等温吸附线,滞后环类型以H3型为主,部分兼有H2特征,反映孔隙主要为平行板状孔。FHH方程计算的页岩孔隙分形维数D值在2.66~2.71之间,数值接近3,表明页岩孔隙结构较为复杂,其非均质性较强,而微小孔发育是造成页岩孔隙结构非均质性的主要原因。
[Abstract]:The micropore characteristics of marine and continental transitional shale of Taiyuan formation in Ningwu Basin were observed by scanning electron microscope (SEM). The pore structure was studied by means of NMR technique and nitrogen adsorption experiment at low temperature. The results show that there are mainly organic pore, mineral intergranular pore, mold pore and microfissure in marine and continental transitional shale of Taiyuan formation in Ningwu Basin, and the characteristics of T2 spectrum of shale sample are similar, showing bimodal in shape, the peak value is between 0.81ms and 2050ms, respectively. According to the height of left peak, it can be divided into two types: peak T2 spectrum and low peak T2 spectrum. The maturity of peak T2 spectrum sample is low, the organic carbon content is high, and the low peak T2 spectrum sample has high maturity and low organic carbon content. The results indicated that the organic carbon content and maturity might affect the development of pores, and the results of low temperature nitrogen adsorption experiments showed that the samples had type 鈪，

本文编号：2108220