| 南方下古生界海相页岩极低电阻率成因及其地质意义 |
| |
| 引用本文： | 侯宇光,张坤朋,何生,覃魏峰,肖艳,王成,余锐.南方下古生界海相页岩极低电阻率成因及其地质意义[J].地质科技通报,2021,40(1):80-89. |
| |
| 作者姓名： | 侯宇光 张坤朋 何生 覃魏峰 肖艳 王成 余锐 |
| |
| 作者单位： | 中国地质大学（武汉）构造与油气资源教育部重点实验室;宁波市交通规划设计研究院有限公司;湖北省地质实验测试中心 |
| |
| 基金项目： | 国家自然科学基金项目41772143国家科技重大专项子课题2016ZX05034002-003中国地质调查局项目DD20190561-1 |
| |
| 摘 要： | 基于测井电阻率和有机地球化学数据,利用页岩极化率测试和干酪根激光拉曼测试等技术手段,对导致南方下古生界高演化海相页岩呈现极低电阻率(测井电阻率低至10~1Ω·m及以下)的主控因素进行了分析,深入探究了其内在成因,并对其地质意义进行了探讨。结果显示:有机质丰度和成熟度是影响极低电阻率测井的主要因素;w(TOC)与测井电阻率和实测电阻率均呈现出良好的负相关关系;成熟度越高,达到极低电阻率所需要的最低w(TOC)界限值越低,页岩的极化率也随之增加。石墨化的有机质是致使高演化页岩出现极低电阻率的主要“导电矿物”,有机质开始发生石墨化的“临界点”对应的Rmc Ro约为3.5%。极低电阻率特征是页岩有机质结构发生显著变化、向石墨化演进的重要标志。极低电阻率测井响应预示着页岩储层品质极可能遭受了巨大的损害:生烃能力枯竭、有机质孔隙大幅减少、吸附性能降低、含气性骤降。因此,圈定极低电阻率页岩范围,排除“有机质石墨化”的高风险区,对下古生界高演化海相页岩选区评价具有重要意义。
|
| 关 键 词： | 石墨化 极低电阻率 海相页岩 高演化 下古生界 |
| 收稿时间： | 2019-12-25 |
Origin and geological significance of ultra-low resistivity in Lower Paleozoic marine shale,South China |
| |
| Hou Yuguang,Zhang Kunpeng,He Sheng,Qin Weifeng,Xiao Yan,Wang Cheng,Yu Rui.Origin and geological significance of ultra-low resistivity in Lower Paleozoic marine shale,South China[J].Bulletin of Geological Science and Technology,2021,40(1):80-89. |
| |
| Authors: | Hou Yuguang Zhang Kunpeng He Sheng Qin Weifeng Xiao Yan Wang Cheng Yu Rui |
| |
| Institution: | (Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education,China University of Geosciences(Wuhan),Wuhan 430074,China;Ningbo Communications Planning Institute CO.,LTD,Ningbo Zhejiang 315192,China;Hubei Geological Research Laboratory,Wuhan 430034,China) |
| |
| Abstract: | Combining with the data of logging resistivity and organic geochemistry, polarizability test and Laser Raman spectra were used to analysze the main controlling factors of ultra-low resistivity (logging resistivity as low as 10-1 Ω·m and below) in the high evolution marine shale of Lower Paleozoic, southern China.Moreover, its internal cause and geological significance were also discussed in this paper.Results showed:1) The abundance and maturity of organic matter (OM) are the main factors affecting the ultra-low logging resistivity.There is a good negative correlation between TOC, logging resistivity and measured resistivity.Increasing of maturity will lead to the decrease in the minimum TOC threshold required to achieve ultra-low resistivity, and the polarizability of shale also increases.2) Graphitized OM is the main "conductive mineral" that causes ultra-low resistivity in high thermal evolution shales.The RmcRo corresponding to the critical point at which the OM begins to graphitize is about 3.5%.Extremely low resistivity is an important indicator that the structure of shale organic matter changed significantly and evolved to graphite.3) Logging response of the ultra-low resistivity is likely to indicate that the quality of shale reservoir has suffered great damage, such as exhaustion of hydrocarbon generation capacity, severely reduction of OM pores and adsorption capacity, and abruptly decline of gas content.Therefore, delineating the range of extremely low resistivity shale and excluding the high-risk area of "OM graphitization" could play a great significance role in shale gas assessment and target selection in high evolution Lower Paleozoic shale. |
| |
| Keywords: | graphitization ultra-low resistivity marine shale high evolution Lower Paleozoic |
| 本文献已被 维普 等数据库收录！ |
| 点击此处可从《地质科技通报》浏览原始摘要信息 |
| 点击此处可从《地质科技通报》下载免费的PDF全文 |
|
