TITLE:
Detection of Quarry Blasts in the Koyna-Warna Region, Western India
AUTHORS:
D. Shashidhar, K. Mallika, N. Purnachandra Rao, H. V. S. Satyanarayana, H. K. Gupta
KEYWORDS:
Quarry Blasts, Koyna, Reservoir, Seismicity, Warna, Frequency
JOURNAL NAME:
Open Journal of Earthquake Research,
Vol.3 No.4,
November
28,
2014
ABSTRACT: Koyna-Warna is a seismically active region, characterized by earthquakes triggered by loading of artificial water reservoirs. In this region quarrying is ongoing and sometimes the quarry blasts are confused with triggered seismic events. About 410 events around a known mining area were ob-served during January 2007-October 2013. In general the quarry blasts are carried out mostly during the day time. Based on this fact a well known method of [1] is implemented, which has the capability of detecting the areas of quarry blast activity. Also, discrimination of quarry blasts from earthquakes has been achieved by studying waveforms at key seismic stations located close to the quarrying area. Further, distinction is achieved through spectral analysis in the frequency band of 3 - 15 Hz. Ratio of day-time to night-time events, waveform pattern and spectral analysis approach confirm the presence of quarry blasts aligned south-east of the Warna reservoir.