基于随钻电阻率测井的天然气水合物赋存类型的识别方法  

Identification method of gas hydrate morphologies based on analysis of logging while drilling resistivity

作　　者：龚智 王秀娟 周吉林 邓炜 匡增桂 苏丕波 闫伟超 李三忠[1,2] GONG Zhi;WANG Xiujuan;ZHOU Jilin;DENG Wei;KUANG Zenggui;SU Pibo;YAN Weichao;LI Sanzhong(Frontiers Science Center for Deep Ocean Multispheres and Earth System,Key Laboratory of Submarine Geosciences and Prospecting Techniques,MOE and College of Marine Geosciences,Ocean University of China,Qingdao,Shandong 266100,China;Laboratory for Marine Mineral Resources,Qingdao Marine Science and Technology Center,Qingdao,Shandong 266237,China;National Engineering Research Center of Gas Hydrate Exploration and Development,Guangzhou Marine Geological Survey,China Geological Survey,Guangzhou,Guangdong 511458,China;Sanya Institute of South China Sea Geology,Guangzhou Marine Geological Survey,China Geological Survey,Sanya,Hainan 572000,China)

机构地区：[1]深海圈层与地球系统教育部前沿科学中心,海底科学与探测技术教育部重点实验室,中国海洋大学海洋地球科学学院,山东青岛266100 [2]青岛海洋科技中心海洋矿产资源评价与探测技术功能实验室,山东青岛266237 [3]天然气水合物勘查开发国家工程研究中心,中国地质调查局广州海洋地质调查局,广东广州511458 [4]中国地质调查局广州海洋地质调查局三亚南海地质研究所,海南三亚572000

出　　处：《地质学报》2024年第9期2709-2722,共14页Acta Geologica Sinica

基　　金：国家重点研发计划项目(编号2021YFC2800901);国家自然科学基金项目(编号42376058);海南省重点研发项目(编号ZDYF2024GXJS002)联合资助的成果。

摘　　要：海洋天然气水合物赋存类型多样,识别赋存类型对精准评价水合物的储层物性及资源量具有重要意义。随钻测井与岩芯联合能定量计算水合物储层特性,但水合物取芯难度大、成本高,大量钻井仅实施了部分取芯或无取芯。环形电阻率与速度联合能识别含水合物层,但研究发现裂隙充填型与孔隙充填型水合物可能都具有高环形电阻率和高纵波速度测井响应,二者联合难以直接识别水合物赋存类型。本文分析了不同源距的电磁波电阻率,通过不同电阻率参数的交会分析,发现在裂隙充填型水合物地层,不同源距的高频电磁波电阻率存在明显的分离,高频相位电阻率中最为显著,而在孔隙充填型水合物地层中,电磁波电阻率耦合较好。通过环形电阻率与电磁波电阻率的联合对比,发现在裂隙充填型水合物地层的电磁波电阻率异常更高,而在孔隙充填型水合物地层,环形电阻率的异常更高。研究认为电磁波电阻率对高角度裂隙的响应更加敏感,能有效识别不同赋存类型的水合物,对于水合物的勘探和评价具有重要意义。Marine natural gas hydrates exhibit diverse morphologies,making accurate identification crucial for evaluating reservoir properties and resources.While integrating logging-while-drilling(LWD)with coring data offers quantitative assessment,coring operation sare complex and expensive,often resulting in partial or no data at most drilling sites.Combining ring resistivity and velocity logging can identify gas hydratebearing sediments but cannot distinguish between fracture-filling and pore-filling hydrates due to similar high values in both parameters.Our analysis of electromagnetic wave resistivities at various sourcereceiver spacings and crossplots of multiple resistivity parameters reveals distinct anomaliesin fracturefilling gas hydrate formations,particularly in high-frequency phase resistivity.Conversely,pore-filling hydrate formations exhibit consistent electromagnetic wave resistivities.Comparing electromagnetic wave resistivity and ring resistivity reveals a key difference:electromagnetic wave resistivity shows obvious high-value anomalies in fracture-filling hydrate formations,while ring resistivity exhibits similar anomalies in pore-filling hydrate formations.We propose that the electromagnetic wave resistivity is sensitive to high-angle fractures and effectively discriminates between different gas hydrate morphologies.This sensitivity is highly valuable for exploring and evaluating gas hydrate reservoirs.

关 键 词：电磁波电阻率 环形电阻率 裂隙充填型水合物 孔隙充填型水合物 交会分析 

分 类 号：P618.13[天文地球—矿床学] P631.81[天文地球—地质学]