华南地震

选取了雅砻江锦屏一级水电站水库蓄水后 ,四川省木里县项脚乡一带( 27.6°~28.2°N､101.1°~101.7°E )研究范围内, 2012年3月至2016年9月30日ML≥2.0级的1939次地震进行单台波速比计算,结果显示:库区下闸蓄水后四个阶段 ,5个台站均呈现出了各阶段波速比均值上升的现象 ,表明在库区的加卸载以及库水的长期渗透作用下库区及附近的介质逐渐发生了改变。

Selecting Xiangjiao Town ( 27.6°~28.2°N､101.1°~101.7°E ) of Muli County,Sichuan Province at the reservoir area of Yalong River Jinping Level I Hydropower Station after retaining water as research scope,this paper calculated single station wave velocity ratio of 1939 earthquakes with ML ≥2.0 from Mar 2012 to Sep 30th ,2016. The results show that the five stations experienced the rise of mean wave velocity ratio at various stages during the four stages after retaining water at reservoir area, indicating that the medium at reservoir area and its vicinity experienced variations under the loading and unloading of reservoir area and the long-term permeation of reservoir water.

引言
1 锦屏一级水电站水库各阶段蓄水及木里地区地震活动概况
2 波速比变化的原理与计算方法
3 资料选取情况
4 波速比变化与水库蓄水活动的关系
5 结论

图1 锦屏一级水电站蓄水地震频次与水位对应随时间变化<br/>Fig.1 Time variation of earthquake frequency and water level in Jinping Level I Hydropower Station

图1 锦屏一级水电站蓄水地震频次与水位对应随时间变化
Fig.1 Time variation of earthquake frequency and water level in Jinping Level I Hydropower Station

图2 雅砻江波速比研究震群及台站分布图<br/>Fig.2 Distribution map of earthquake swarms and stations in the study of wave velocity ratio in Yalong River

图2 雅砻江波速比研究震群及台站分布图
Fig.2 Distribution map of earthquake swarms and stations in the study of wave velocity ratio in Yalong River

图3 第二阶段蓄水期四个台站地震波速比随时间的演化进程<br/>Fig.3 Evolution process of seismic wave velocity ratio with time at four stations During the second impoundment period

图3 第二阶段蓄水期四个台站地震波速比随时间的演化进程
Fig.3 Evolution process of seismic wave velocity ratio with time at four stations During the second impoundment period

图4 第三阶段蓄水期五个台站地震波速比随时间的演化进程<br/>Fig.4 Evolution process of seismic wave velocity ratio with time at five stations during the third impoundment period

图4 第三阶段蓄水期五个台站地震波速比随时间的演化进程
Fig.4 Evolution process of seismic wave velocity ratio with time at five stations during the third impoundment period

图5 第四阶段蓄水期五个台站地震波速比随时间的演化进程<br/>Fig.5 Evolution process of seismic wave velocity ratio with time at five stations during the fourth impoundment period

图5 第四阶段蓄水期五个台站地震波速比随时间的演化进程
Fig.5 Evolution process of seismic wave velocity ratio with time at five stations during the fourth impoundment period

图6 正常运行期五个台站地震波速比随时间的演化进程<br/>Fig.6 Evolution process of seismic wave velocity ratio with time at five stations during normal operation period

图6 正常运行期五个台站地震波速比随时间的演化进程
Fig.6 Evolution process of seismic wave velocity ratio with time at five stations during normal operation period

表1 雅砻江水库波速比均值计算结果<br/>Table 1 Calculation results of mean of wave velocity ratio of Yalong River Reservoir

表1 雅砻江水库波速比均值计算结果
Table 1 Calculation results of mean of wave velocity ratio of Yalong River Reservoir

图7 各蓄水阶段与正常运行期五个台站的平均波速比变化<br/>Fig.7 Variation of average wave velocity ratio of five stations during each impoundment stage and normal operation period

图7 各蓄水阶段与正常运行期五个台站的平均波速比变化
Fig.7 Variation of average wave velocity ratio of five stations during each impoundment stage and normal operation period

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备注

引言

1 锦屏一级水电站水库各阶段蓄水及木里地区地震活动概况

2 波速比变化的原理与计算方法

3 资料选取情况

4 波速比变化与水库蓄水活动的关系

5 结论

期刊信息