剑川—德钦一带的地热异常:对川滇菱块西北边界和地震活动性的意义  

Geothermal Anomalies in the Jianchuan-Deqin Region: Constraints on the Northwest Boundary of Sichuan-Yunnan Rhombic Block and Seismic Activity

作　　者：李其林[1] 王云[1,2,3] 周艺颖 赵慈平 LI Qi-lin;WANG Yun;ZHOU Yi-ying;ZHAO Ci-ping(Earthquake Administration of Yunnan Province,Kunming 650224,China;Institute of Geophysics,China Earthquake Administration,Beijing 100081,China;Key Laboratory of Crustal Dynamics,Institute of Crustal Dynamics, China Earthquake Administration,Beijing 100085,China)

机构地区：[1]云南省地震局,昆明650224 [2]中国地震局地球物理研究所,北京100081 [3]中国地震局地壳应力研究所地壳动力学重点实验室,北京100085

出　　处：《矿物岩石地球化学通报》2019年第1期90-102,共13页Bulletin of Mineralogy, Petrology and Geochemistry

基　　金：云南省地震局科技专项(ZX2016-03);国家自然科学基金项目(41502315)

摘　　要：为研究川滇菱块西北缘剑川-德钦一带地热场空间分布特征,探索地热异常区与断裂及地震活动性的关系以及活动块体边界问题,运用4种传统地热温标和多矿物平衡法综合估算了川滇菱块滇西北地区(德钦-维西-剑川-丽江-中甸) 91个地热温泉的最有可能的热储温度,通过克里金插值方法获得了滇西北地区的热储温度空间分布。结果表明,地热异常区主要沿德钦-中甸-大具断裂及其以北的多条近南北向金沙江断裂的分支断层展布,澜沧江断裂带、维西-马登断裂、玉龙雪山东麓断裂和中甸-龙蟠-乔后断裂局部分段表现地热异常;地热异常区的地理展布大致反映了德钦-中甸-大具断裂与金沙江断裂带共同构成了川滇菱形块体的西北边界;绝大多数中强地震震中位于地热中-高值区即地热的横向梯度带上,德钦-中甸-稻城一带地热横向梯度变化较大且历史上强震稀少,未来的地震危险性值得关注。The relationships between the temperature geothermal anomaly and the activity of faults and seism are investigated to further understand the location of the northwest boundary of the Sichuan-Yunnan Rhombic Block by obtaining the spatial distribution of shallow geothermal field in the Jianchuan-Deqin Region. In this paper,four different classical geothermometers and multi-mineral balance methods are used to calculate the temperature of geothermal reservoirs by using 91 chemical data of hot spring water in northwestern Yunnan and the Kriging Interpolation Method is used to obtain the spatial distribution pattern of reservoir temperature in Deqin-Weixi-Jianchuan-Lijiang-Zhongdian. The results show that the geothermal anomaly is distributed along the Deqin-Zhongdian-Daju Fault in the south and several near-SN trending branche faults of the Jinshajiang Fault in the north. Parts of the Lancangjiang,Weixi-Qiaohou,Jade Dragon Snow Mountain and Zhongdian-Longpan-Qiaohou faults display the high temperature geothermal anomaly as well. The spatial distribution pattern of geothermal anomalies reveals that the Deqin-Zhongdian-Daju Fault together with the Jinshajiang Fault constitutes the Northwest boundary of Sichuan-Yunnan Rhombic Block. The vast majority of M≥5. 0 earthquakes are located in the geothermal middle-high value zone,the seismic risk in northwestern Yunnan future deserves concern in the Deqin-Zhongdian-Daocheng zone due to large variation of geothermal horizontal gradient.

关 键 词：剑川-德钦一带 温泉 热储温度 地热异常 断裂 地震 

分 类 号：P314[天文地球—固体地球物理学]