摘要
珠江三角洲地区是否存在晚第四纪的断裂活动是大湾区战略规划的一个重要参考因素。活动断裂带内第四纪松散沉积物是断层活动的主要标志及信息载体,细致、立体地观测松散沉积物并非易事。通过采用X射线全岩芯扫描技术,对珠江三角洲地区主要断裂带上的钻孔岩芯进行了扫描和处理,使用体渲染技术对岩芯的三维结构进行可视化,重点观测第四系未固结沉积物的变形现象。研究表明,岩芯CT扫描图像不仅克服了未固结岩芯难以自由转动、无法开展多角度观测的困难,而且可以揭示大量在岩芯照片上无法观察到的现象,如岩芯的内部非均匀结构、物质分布情况、裂缝的展布形态,以及裂缝处的物质成分变化等。结合沉积物测年结果,可以给出断裂活动时间。因此,对于未固结沉积物钻孔岩芯,全岩芯CT扫描可以作为优选的观测、分析新手段,在未来的工程探查和活动断裂研究中加以推广。
The presence of Late Quaternary faults in the Pearl River Delta region is an important factor that may affect the development of the Greater Bay Area.Loose Quaternary sediments within active fault zones are the main markers and information carriers of fault activity,comprehensive observations of loose sediments from the point view of three-dimension are difficult.In this study,borehole cores from the main fault zones in Xilingang,Guangzhou were X-ray CT scanned using whole-core scanning devices,images were processed and visualized by using the volume rendering technique to investigate the 3D structures of the cores focusing on the deformation of Quaternary unconsolidated sediments.The study demonstrates that the CT scan of borehole cores enables us to virtually observe cores with reality from different perspectives by free rotations,which is impossible to reach physically for unconsolidated cores,and further reveals a large number of phenomena that cannot be observed from conventional core photographs,including the internal heterogeneous structures,the distribution of materials,and the extending pattern and compositions of fractures.Combined with the dating results of sediments,the time of fault activity can be estimated.Therefore,whole-core CT scanning can be a preferred new method for studying unconsolidated borehole cores and is recommended for geological exploration and active fault investigations in areas covered by soft sediments.
作者
加依娜·叶尔扎提
陈震
张献河
林小明
吴维盛
黄孝波
闫亚鹏
汤永杰
刘洁
JIAYINA Yeerzhati;CHEN Zhen;ZHANG Xianhe;LIN Xiaoming;WU Weisheng;HUANG Xiaobo;YAN Yapeng;TANG Yongjie;LIU Jie(School of Earth Sciences and Engineering,Sun Yat-sen University,Guangdong Zhuhai 519082,China;Xinjiang Baodi Mining Co.,Ltd.,Urumqi 830000,China;GDZD Institute on Deep-Earth Sciences Co.,Ltd.,Guangzhou 510275,China;Geological Survey of Guangdong Province,Guangzhou 510080,China;Guangdong Foshan Geological Survey,Guangdong Foshan 528000,China;Guangdong Provincial Key Laboratory of Mineral Resources&Geological Processes,Guangdong Zhuhai 519082,China;Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai),Guangdong Zhuhai 519082,China)
出处
《地球科学进展》
CAS
CSCD
北大核心
2023年第8期866-878,共13页
Advances in Earth Science
基金
广东省国土资源保护与治理专项资金项目“珠江三角洲基底断裂探查与研究”(编号:2017201)
“佛山市南海区城市地质调查”(编号:JF2021(NH)WZ0246)资助.
关键词
三维数字岩芯
第四纪
软沉积物
变形
珠江三角洲
3D digital core
Quaternary
Soft sediments
Deformation
Pearl River Delta
作者简介
加依娜·叶尔扎提(1996-),女,新疆阿勒泰人,硕士研究生,主要从事岩石微观CT技术应用.E-mail:jiayina@mail2.sysu.edu.cn;通信作者:刘洁(1967-),女,江西宜丰人,教授,主要从事计算地球动力学及微观层析成像技术与应用研究.E-mail:liujie86@mail.sysu.edu.cn
