气枪信号触发台站的自动快速识别

气枪震源是高度可重复的人工震源,在深部探测工作中应用广泛。以福建省地震局组织开展的水库气枪实验为研究对象,面向未来技术的发展,提出基于气枪激发波形的相关性计算,自动获取气枪信号触发台站情况,并绘制触发台站的分布图。对处理结果分析认为:该方法能快速准确识别触发台站,可迅速作出分布图,直观地反应气枪激发效果,较好地为实验现场实验条件的调整提供依据。

Automatic Detection of Stations Triggered by Air-gun Signals

The air-gun source, first invented in the 1960s, is mainly used in the field of oil exploration. It has high precision, good repeatability, and is non-polluting; thus, it has gradually become an important artificial source in geophysical detection area. The earthquake administration of Fujian Province efficiently completed the construction of its air-gun source system and has successfully carried out a series of air-gun explosion experiments in 2014 and 2015, thus providing valuable observation data for further research. Considering that the experimental conditions of the air-gun array and the explosion conditions directly affect the explosion performance, researchers have designed a series of air-gun explosion experiments under different experimental conditions. After each experiment, the explosion capability must be quickly analyzed to determine an optimal operating condition for the consecutive explosion issue. At present, the whole analysis work is completed by manual work. This process requires a lot of work, time, and effort, so analysts need to work overtime. Thus, this process is not only inefficient but also subjective because different analysts may provide different results. Considering the further application of this repeatable source, a new method based on the correlation coefficient method is proposed to automatically analyze and display the distribution of air-gun trigged stations. Analysis results show that the new method obtains the same results as the artificial judgments. The K24 and K36 experiment results show better explosion effect. Moreover, over 70 stations received the signals of single firing, with signals that can be recorded by stations beyond 200 km. After repeating the firing for 50 times, over 90 stations received the signals, which can be recorded by stations beyond 226 km. The automatic detection method provides a faster and more objective way to demonstrate the distribution of the trigged stations, thus significantly contributing to the air-gun explosive effect evaluation process. The automatic detection method was successfully applied in subsequent experiments carried out in the Mianhuatan Reservoir (Longyan, Fujian) and Shihuangfeng (Wuping, Fujian).