作者：施斌1*, 王宝善2, 张诚成1, 顾凯1, 阮友谊1, 李广伟1, 王勤1, 魏广庆3, 张丹1, 朱鸿鹄1, 程刚1, 陈颙1
1. 南京大学地球科学与工程学院, 南京210023;
2. 中国科学技术大学地球和空间科学学院, 地震与地球内部物理实验室, 合肥230026;
3. 南京大学(苏州)高新技术研究院, 苏州215123
摘要：川西甲基卡锂矿3211 m科学深钻位于青藏高原东缘鲜水河断裂及川藏铁路附近, 是目前青藏高原上最深的科学钻孔. 利用此深钻观测深部物理场和浅部环境的变化过程, 对于研究青藏高原地壳活动、川藏铁路场地稳定性和生态环境保护等均具有重要意义. 采用分布式光纤传感(distributed fiber optic sensing, DFOS)技术, 我们研发了高强度、耐高温的特种传感光缆, 成功植入甲基卡锂矿深钻中, 建成了世界上海拔最高和深度最大的光纤观测孔, 实现了应变、温度、振动、水分等多物理量的分布式原位观测. 本文是甲基卡光纤观测孔第一阶段的成果, 包括岩体热导率的原位测定、钻孔回填过程的分布式声波振动(distributed acoustic sensing, DAS)观测、地震监测与地震成像等方面的初步进展. 研究表明: DFOS应用于深钻全断面多物理量观测是可行的, 它完全能适应深钻高温和高压的观测环境, 并具有长距离、实时、连续分布式观测的优势; 将分布式温度传感光纤、应变传感光纤和声波传感光纤集于一根传感光缆的设计思路保障了深钻传感光缆的安装质量, 并为DFOS技术应用于地球物理和地质工程的多物理场观测开辟了广阔的应用空间.
关键词：钻孔观测, 分布式光纤传感, 多物理量, 甲基卡, 地震监测
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引用格式: 施斌, 王宝善, 张诚成, 等. 川西甲基卡锂矿3211 m科学深钻多物理量分布式光纤观测. 科学通报, 2022, 67: 1–8
Shi B, Wang B S, Zhang C C, et al. Multi-physical distributed fiber optic observation in a 3211-m-deep scientific borehole at Jiajika lithium mine, western Sichuan (in Chinese). Chin Sci Bull, 2022, 67: 1–8, doi: 10.1360/TB-2021-1380