A Low-Power Two-Stage Seismic Sensor Scheme for Earthquake Early Warning System

The north-eastern, Himalayan, and Eastern Ghats Belt
of India comprise of earthquake-prone, remote, and hilly terrains.
Earthquakes have caused enormous damages in these regions in the
past. A wireless sensor network based earthquake early warning
system (EEWS) is being developed to mitigate the damages caused
by earthquakes. It consists of sensor nodes, distributed over the
region, that perform majority voting of the output of the seismic
sensors in the vicinity, and relay a message to a base station to alert
the residents when an earthquake is detected. At the heart of the
EEWS is a low-power two-stage seismic sensor that continuously
tracks seismic events from incoming three-axis accelerometer signal
at the first-stage, and, in the presence of a seismic event, triggers
the second-stage P-wave detector that detects the onset of P-wave
in an earthquake event. The parameters of the P-wave detector have
been optimized for minimizing detection time and maximizing the
accuracy of detection.Working of the sensor scheme has been verified
with seven earthquakes data retrieved from IRIS. In all test cases, the
scheme detected the onset of P-wave accurately. Also, it has been
established that the P-wave onset detection time reduces linearly with
the sampling rate. It has been verified with test data; the detection
time for data sampled at 10Hz was around 2 seconds which reduced
to 0.3 second for the data sampled at 100Hz.

Authors:

• Arvind Srivastav
• Tarun Kanti Bhattacharyya

Keywords:

• Earthquake early warning system
• EEWS
• STA/LTA
• polarization
• wavelet
• event detector
• P-wave detector.

References:

[1] S. K. Jain, “Indian earthquakes : An overview,” The Indian Concrete
Journal, vol. 72, no. 11, 1998.
[2] D. Rai, G. Mondal, V. Singhal, N. Parool, and P. T., “2011 sikkim
earthquake: Effects on building stocks and perspective on growing
seismic risk,” in 15th World Conference on Earthquake Engineering,
2012.
[3] K. Goda, T. Kiyota, R. M. Pokhrel, G. Chiaro, T. Katagiri,
K. Sharma, and S. Wilkinson, “The 2015 gorkha nepal
earthquake: Insights from earthquake damage survey,” Frontiers
in Built Environment, vol. 1, p. 8, 2015. [Online]. Available:
https://www.frontiersin.org/article/10.3389/fbuil.2015.00008
[4] Y. Nakamura, “Uredas, urgent earthquake detection and alarm system,
now and future,” in 13th World Conference on Earthquake Engineering,
2004.
[5] A. R.M., “The elarms earthquake early warning methodology and its
application across california,” Earthquake Early Warning Systems, pp.
21–24, 2007.
[6] M. B¨ose, M. Erdik, and F. Wenzel1, A New Approach to Earthquake
Early Warning. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007,
pp. 65–83.
[7] R. V. Allen, “Automatic earthquake recognition and timing from single
traces,” Bulletin of the Seismological Society of America, vol. 68, no. 5,
p. 1521, 1978. [Online]. Available: + http://dx.doi.org/
[8] W. Jiang, H. Yu, L. Li, and L. Huang, “A robust algorithm for earthquake
detector,” in 15th World Conference on Earthquake Engineering, 2012.
[9] M. Withers, R. Aster, C. Young, J. Beiriger, M. Harris, S. Moore, and
J. Trujillo, “A comparison of select trigger algorithms for automated
global seismic phase and event detection,” Bulletin of the Seismological
Society of America, vol. 88, no. 1, p. 95, 1998. [Online]. Available: +
http://dx.doi.org/
[10] E. Kanasewich, Time sequence analysis in geophysics. Third Ed., The
University of Alberta Press, Alberta. The University of Alberta Press,
Alberta, 1981.
[11] R. R. Leach and F. U. Dowla, “Earthquake early warning system using
real-time signal processing,” in Neural Networks for Signal Processing
VI. Proceedings of the 1996 IEEE Signal Processing Society Workshop,
Sep 1996, pp. 463–472.
[12] U. Antao, A. Dibazar, J. Choma, and T. Berger, “Low power false
positive tolerant event detector for seismic sensors,” in 2013 IEEE
SOI-3D-Subthreshold Microelectronics Technology Unified Conference
(S3S), Oct 2013, pp. 1–2.