2022年5月13日腾冲ML 3.8地震发生前，3月开始小滇西区域地震频率增强，云南腾冲地区形变面膨胀资料出现显著压缩变化，腾冲地区同步出现静水位破年变、水氡高值异常。基于腾冲区域异常变化，开展流体地球化学取样研究，选取震中距在28—48 km范围内的叠水河冷泉（＜25 ℃）、石墙热泉（45 ℃—55 ℃）、大滚锅沸泉（＞55 ℃），利用多元素综合分析方法，如B/K和K/Li交会图、Cl-Li-B和B-F-Cl三元图等研究流体异常变化，发现震前3个泉点的K/Li比值均显著升高，B在热泉及沸泉中出现高值，而Sr在冷泉及热泉中同样出现高值变化等现象。综合分析认为，基于腾冲地区火山地质及水热条件，在震前具有流体相关逸散性强、溶水性高及易迁移性大的元素，对于地震地球物理异常识别具备研究价值，有助于提升地球化学在地震预测中的研究与应用。
Before the Tengchong ML 3.8 earthquake on May 13, 2022, starting in March, the frequency of earthquakes in the western Yunnan region increased, and the deformation surface expansion data in the Tengchong area of Yunnan showed significant compression changes, along with simultaneously anomalies such as synchronous changes in static water level and a high value in water radon. Based on the anomalous changes in the Tengchong area, fluid geochemical sampling research was conducted. Dieshuihe cold spring (<25℃), Shiqiang hot spring (45℃ -55 ℃), and Dagunguo boiling spring (>55℃) within the epicenter distance of 28-48 km were selected. Multielement comprehensive analysis methods were used, such as the B/K and K/Li cross plot, Cl-Li-B, and B-F-Cl ternary plot, to study fluid anomalous changes. It was found that the K/Li ratio of the three spring points significantly increased before the earthquake, and B showed high values in hot springs and boiling springs, while Sr also showed high value changes in cold and hot springs. According to comprehensive analysis, based on the volcanic geology and hydrothermal conditions in the Tengchong area, there are elements with strong fluid-related escape, high water solubility, and easy migration before earthquakes, which have research value for identifying seismic geophysical anomalies and help improve the research and application of geochemistry in earthquake prediction.
2023,44（6）: 62-69 收稿日期：2023-6-26
DOI：10.3969/j.issn.1003-3246.2023.06.010
基金项目：云南省青年地震科学基金：云南腾冲流体痕量元素与地震活动相关性研究（项目编号：2022K12）
作者简介：杨黎（1993—），男，硕士，工程师，主要从事地震监测预报研究工作。E-mail：1339518135@qq.com
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