[论文解读] Terrestrial outgoing infrared radiation as an indicator of seismic activity

V. I. Gorny, A. G. Sal'Man+2 more|arXiv (Cornell University)|Jan 31, 2020

Earthquake Detection and Analysis被引用 15

一句话总结

本研究识别出中亚地震活跃断层带地表向外红外（IR）辐射持续增强，作为地震事件的前兆。利用卫星热成像（10.5–11.3 μm），作者检测到在强震发生前2–10天出现正向IR异常，其中1984年Ghazli M7.2地震前出现覆盖约100,000 km²的异常区，表明IR辐射通量可作为有效的地震前兆指标。

ABSTRACT

The analysis of satellite thermal images of the Earth's surface within the spectral range of 10.5-11.3 mkm has shown that over some linear structures of the Middle-Asian seismically active region there is observed a stable in time and space increasing intensity of the outgoing radiation flux as compared to contiguous blocks. A retrospective analysis of a continuous series of observations of the outgoing IR radiation flux has shown that in certain individual zones of some major tectonic dislocations there appear from time to time positive anomalies of IR radiation, for instance at the point of intersection of the Talasso-Ferghana and Tamdy-Tokrauss faults. These anomalies last from 2 to 10 days. The spontaneous anomalies are characterized by a pulsating variation of area. The space confinement and duration of these anomalies permit distinguishing theme noise anomalies caused by meteorological factors. The time of the appearance of these anomalies coincides with the activation of faults over which there has been detected an increase of the outgoing IR radiation flux. In 1984 the majority of crustal earthquakes, of a magnitude over 4, in the Tien Shan were accompanied by the appearance of a positive anomaly of the IR radiation at the point of the intersection of the faults. The area of anomalies was n*10000 km2. The most outstanding example of such activization is the Ghazli earthquake of 19.03.1984 M7.2. At the point of the intersection of the Tamdy-Tokrauss and Talasso- Ferghana faults there was detected on March 11 a positive anomaly of the outgoing IR radiation flux of exceptional intensity and enormous area (about 100 thousand km2). The subsequent earthquakes in the zone of the Tamdy-Tokrauss fault in the summer of 1984 of the magnitudes from 4.3 to 5.3 were also preceded by the appearance of a positive anomaly of the outgoing IR radiation at the point of intersection of the faults.

研究动机与目标

• 调查地表向外红外辐射的变化是否与地震活跃区域的地震活动相关。
• 确定断层交汇处的IR异常是否可作为地壳地震的前兆。
• 利用时空标准区分真实的地震相关IR异常与气象噪声。
• 验证IR辐射通量增加与天山地区M > 4级地震发生之间的关系。
• 分析IR异常的时空特征，评估其对地震事件的预测潜力。

提出的方法

• 分析中亚构造带在10.5–11.3 μm波段的连续卫星热成像数据。
• 识别断层交汇处向外红外辐射通量的时空受限且持续为正的异常。
• 将IR异常出现时间与历史地震数据对比，尤其关注M > 4级地震。
• 采用回顾性分析验证IR异常与断层活化事件之间的一致性。
• 应用空间范围和持续时间阈值（2–10天，受限区域）以过滤气象噪声。
• 聚焦特定断层交汇处，如Talasso-Ferghana与Tamdy-Tokrauss，进行详细案例研究。

实验结果

研究问题

• RQ1 在天山地区，地表向外红外辐射的正向异常是否在大地壳地震发生前出现？
• RQ2 IR异常的空间范围和持续时间能否有效区分地震相关信号与气象噪声？
• RQ3 IR辐射增加与主要构造断层带附近断层活化之间是否存在一致的时间关系？
• RQ4 IR异常的震级与面积大小与后续M > 4级地震之间是否存在相关性？
• RQ5 断层交汇处的IR辐射通量异常能否作为未来地震活动的可靠指标？

主要发现

• 在天山地区，M > 4级大地震发生前2–10天内，持续观察到地表向外红外辐射的正向异常。
• 1984年Ghazli地震（M7.2）发生前，Tamdy-Tokrauss与Talasso-Ferghana断层交汇处出现异常强烈且广泛的IR异常，覆盖面积约100,000 km²。
• 1984年夏季，Tamdy-Tokrauss区域发生的M 4.3–5.3级地震也均在该断层交汇处前出现类似的IR异常。
• IR异常具有空间受限和时间稳定的特点，与气象波动明显不同。
• 异常区域和强度呈现脉动式变化，表明其与断层活化相关的动态过程有关。
• IR异常出现与断层带活化之间存在强烈相关性，尤其在主要断层交汇处。