The triggering mechanism of swarm-like seismicity in the Java Island of Indonesia is generally not well understood. Understanding earthquake swarm phenomena in various tectonic settings can be improved by the detection of micro-earthquakes; however, such a catalog is not available due to various reasons including the existing limited seismic network and using an outdated algorithm for event detection. In this study, we analyze the seismic waveforms and explore the detection capability of small earthquakes during the August 2019 earthquake sequence near Mt. Salak (West Java) by using the known matched filter technique (MFT) and relocated events as templates. We analyze continuous waveforms from seven broadband seismic stations in a 150 km radius around the source center and for a ~ 1 month of data. Our derived complete catalog enables us to analyze the frequency-magnitude distribution of the sequence as well as the spatiotemporal evolution of micro-seismicity. The six largest events were hybrid-like-type volcano-tectonic earthquakes with oblique-thrust mechanisms. The relocation procedure shows that all of the events are located within an area of ~ 2 × 2 km², probably bounded at 9–12 km of depth. The pattern of seismicity distribution was not clear; however, focal mechanisms might indicate N/NW or E/SE-trending orientation with a steep plane. We detect 280 additional micro-earthquakes to the improved catalog. The b-value of the sequence is close to 1.1, typical for many volcano-tectonic events. We show that the swarm might be initiated by the fluid intrusion into the seismogenic zone while the stress changes from the largest event affected the evolution of swarm.

在印度尼西亚的爪哇岛，类群地震活动的触发机制通常没有被很好地理解。通过检测微地震可以提高对各种构造背景下的地震群现象的了解；但是，由于各种原因（包括现有的有限地震网络以及使用过时的算法进行事件检测），此类目录不可用。在这项研究中，我们分析了地震波形并探索了2019年8月山附近地震序列中小地震的探测能力。Salak（West Java）通过使用已知的匹配筛选器技术（MFT）和重定位的事件作为模板。我们分析了震源中心周围150公里半径内七个宽带地震台站的连续波形，并获得了约1个月的数据。我们导出的完整目录使我们能够分析序列的频率幅度分布以及微地震的时空演化。六个最大的事件是具有斜推力机制的混合型火山构造地震。迁移过程表明所有事件均位于〜2×2 km的区域内²，可能在9–12 km的深度处。地震活动性分布的模式不明确。但是，震源机制可能表明N / NW或E / SE趋势方向具有陡峭的平面。我们在改进的目录中检测到280次其他微地震。该序列的b值接近1.1，这是许多火山构造事件的典型值。我们表明，群可能是由流体侵入成地震带而引发的，而最大事件的应力变化影响了群的演化。