陆相泥页岩层系岩相测井识别与预测:以南堡凹陷拾场次洼为例  

Logging identification and prediction of lithofacies of lacustrine shale system in Shichang Sub-Sag,Nanpu Depression

作　　者：曾棒 刘小平[1,2] 刘国勇[3] 王绍春[3] 李国永[3] Zeng Bang;Liu Xiaoping;Liu Guoyong;Wang Shaochun;Li Guoyong(State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum(Beijing),Beijing 102249,China;College of Geosciences,China University of Petroleum(Beijing),Beijing 102249,China;Jidong Oilfield Company,PetroChina,Tangshan Hebei 063004,China)

机构地区：[1]中国石油大学(北京)石油资源与探测国家重点实验室,北京102249 [2]中国石油大学(北京)地球科学学院,北京102249 [3]中国石油冀东油田分公司,河北唐山063004

出　　处：《地质科技通报》2021年第1期69-79,共11页Bulletin of Geological Science and Technology

基　　金：国家科技重大专项课题(2017ZX05049001-008);国家自然科学基金项目(41372144;42072150)。

摘　　要：泥页岩层系岩相研究是页岩油勘探的基础工作,由于钻井取心较为困难且陆相湖盆范围小,相变快,使岩相精细识别与预测较为困难。测井曲线精确度高,纵向连续性好,可以准确识别与预测岩相。利用全岩X衍射(XRD)、薄片鉴定及地球化学分析测试等实验数据,将岩相按“三级次-三单元”划分方案进行划分,将测井曲线与TOC值、矿物含量等参数进行拟合,综合识别岩相,最后在高分辨率层序格架下建立岩相旋回叠加模式,从而进行岩相展布研究。结果表明该地区为一套以Ⅰ型和Ⅱ1型干酪根为主生油湖相烃源岩,可划分为18种岩相,其中富有机质黏土质层状泥岩、富有机质混合质纹层状泥岩、页岩为页岩油优势岩相。岩相各评价指标可通过测井曲线计算与预测。岩相与层序存在耦合关系,在等时地层格架下具可预测性。沙三4亚段泥页岩层系岩相在此格架下,形成了MSC1中部与MSC2两个有机质富集层,以及SQ5~SQ8上升半旋回4个沉积构造发育带。The study of the lithofacies of shale formation is the basic work for shale oil exploration.Due to the limited distribution of the continental lacustrine basin and the fast variations of lithofacies,it is difficult to accurately identify and predict the lithofacies.With high precision and good continuity in vertical direction,the logging curve can be used to accurately identify and predict the lithofacies.Based on the experimental data of whole-rock X-ray diffraction(XRD),thin-section identification and geochemical analysis data,the lithofacies can be divided according to the division scheme named three classes&ternary plots.Fitting logging data with TOC value and mineral content,the lithofacies can be comprehensively identified.Finally,the cycle superposition model of lithofacies is established under the high-resolution sequence frame to study the distribution of lithofacies.The results show that the area is a set of oil-bearing lacustrine source rocks with Ⅰ and Ⅱ1 kerogen,which can be divided into 18 types of lithofacies,among which organic-rich argillaceous lamellar shale and organic-rich mixed lamellar shale are the dominant lithofacies.The evaluation indexes of the lithofacies can be calculated and predicted through the logging curve.There is a coupling relationship between the lithofacies and the sequence so that the lithofacies are predictable under the isochronous stratigraphic framework.The lithofacies of shale formation of the Es3^4 sub-member are under this framework,forming two organic-rich layers located in the middle of MSC1 and MSC2 middle cycles and four sedimentary tectonic development zones corresponding to the SQ5-SQ8 ascending semi-cycling.

关 键 词：南堡凹陷 泥页岩层系 岩相 测井 等时地层格架 

分 类 号：P631[天文地球—地质矿产勘探]