山东鲁西地区上古生界泥页岩特征及页岩气远景区预测

Characteristics of Upper Paleozoic Shales and Prediction of Shale Gas Prospective Area in Luxi Area of Shandong Province

摘要:

基于区内石油、地矿、煤田勘查开发等与页岩气有关地质矿产资料和基础地质勘查成果，以上古生界石炭二叠系暗色泥页岩沉积环境与分布特征、有机地球化学特征为重点，对鲁西地区上古生界页岩气资源勘探远景进行初步预测。研究表明山东鲁西地区上古生界发育山西组、太原组和黑山组3套厚度较大的暗色泥页岩层系，形成于有机质丰富的沉积环境，总体表现为由克拉通盆地陆表海沉积演化为近海河流三角洲湖泊沉积；厚度31～193m，埋深240～4000m；有机碳（TOC）含量1.8%～2.6%；有机质类型主要为Ⅱ2，Ⅲ型干酪根；且以Ⅲ型干酪根为主；镜质体反射率（Ro）平均值为0.7%～1.0%，处于成熟阶段。综合各种成藏条件，认为鲁西地区上古生界暗色泥页岩具有良好的页岩气形成条件。根据非常规能源（页岩气和油）远景区（带）划分主要技术指标，初步预测了曹县煤田、鱼台凹陷、黄河北煤田、阳谷茌平煤田共4个远景区。

Abstract:

Based on geological mineral data and basic geological exploration results related with shale gas, such as petroleum, mining and coal exploration, regarding upper Paleozoic CarboniferousPermian sedimentary environment and distribution characterisitcs of dark shales as well as organic geochemical characteristics as the focus, exploration prospects of upper Paleozoic shale gas in Luxi area has been predicated primarily. It is showed that three dark shale formations with great thickness developed in the upper Paleozoic in Luxi area, they are Shanxi formation, Taiyuan formation and Heishan formation. They are formed in the sedimentary environment which is abundant in organics that are easily preserved. The sedimentary environment is generally from cratonic basin epicontinental sedimentary to offshore river delta lacustrine sedimentary. The thickness is 31~193m, the depth is 240~4000m, TOC is 1.8%～2.6%,organic matter is mainly type Ⅲ, followed by typeⅡ2, the average value of Ro is 0.7%～1.0% showing in the gas stage of mature. Based on comprehensive analysis of these conditions, it is revealled that the upper Paleozoic dark shales have good conditions of producing shale gas. According to dividing indices of the unconventional energy (shale gas and oil)prospect areas(zones), four prospective areas have been predicated, they are Caoxian coal mine, Yutai depression, Huanghebei coal mine and YangguChiping coal mine.