Preliminary Chaos Analyses of Explosion Earthquakes Followed by Harmonic Tremors at Semeru Volcano, East Java, Indonesia

Authors: Sukir Maryanto, Didik R. Santosa, Iyan Mulyana, Muhammad Hendrasto

Abstract:

Successive event of explosion earthquake and harmonic tremor recorded at Semeru volcano were analyzed to investigate the dynamical system regarding to their eruptive mechanism. The eruptive activity at Semeru volcano East Java, Indonesia is intermittent emission of ash and bombs with Strombolian style which occurred at interval of 15 to 45 minutes. The explosive eruptions accompanied by explosion earthquakes and followed by volcanic tremor which generated by continuous emission of volcanic ash. The spectral and Lyapunov exponent of successive event of explosion and harmonic tremor were analyzed. Peak frequencies of explosion earthquakes range 1.2 to 1.9 Hz and those of the harmonic tremor have peak frequency range 1.5 — 2.2 Hz. The phase space is reconstructed and evaluated based on the Lyapunov exponents. Harmonic tremors have smaller Lyapunov exponent than explosion earthquakes. It can be considerably as correlated complexity of the mechanism from the variance of spectral and fractal dimension and can be concluded that the successive event of harmonic tremor and explosions are chaotic.

Keywords: Semeru volcano, explosion earthquakes, harmonic tremor, lyapunov exponent, chaotic.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1072475

References:

[1] K Kusumadinata, "Catalogue of References on Indonesian Volcanoes with Eruptions in Historical Time", Volcanological Survey of Indonesia, pp 304, 1979
[2] S Siswowidjoyo, U Sudarsono, A D Wirakusumah, "The threat of hazards in the Semeru volcano region in East Java, Indonesia," Journal of Asian Earth Sciences, vol 15; pp. 185-194, 1997
[3] I Mulyana, "Characteristics of harmonic tremor at Semeru volcano, East Java, Indonesia," JICA Final Report of Volcanology and Comprehensive Sediment-related Disaster Prevention Measures J05-00876, 2006)
[4] K Nishi, M Hendrasto, I Mulyana, U Rosadi, M A Purbawinata, "Micro-tilt changes prior to the summit explosions at Semeru volcano, Indonesia" Earth, Planets and Space, vol. 59; pp. 151-159, (2007
[5] S Maryanto, M Iguchi, and T Tameguri, "Spatio-Temporal Characteristics on Spectra and Particle Motion of Harmonic Tremors at Sakurajima Volcano, Japan," Ann. Disast. Prey. Res. Inst., Kyoto University, vol. 48B, pp. 329-339, Apr. 2005
[6] S Maryanto, I Mulyana, "Temporal Change of Fractal Dimension of Explosion Earthquakes and Harmonic Tremors at Semeru volcano, East Java, Indonesia, using Critical Exponent Method", Intl. Journal of Math. Physical and Engineering Sciences, vol. 3, pp. 113-117, 2009
[7] M Nakagawa, "Chaos and Fractal in Engineering," Singapore: World Scientific, 1999, ch. 3.
[8] L Cao, "Practical method for determining the minimum embedding dimension of scalar time series", Physica D, vol. 110, pp 43-50, 1997
[9] M B Kennel, R Brown and H D I Abarbanel, "Determining embedding dimension for phase-space reconstruction using a geometrical construction", Phys. Rev. A, vol. 45, pp. 3403-3411, 1992
[10] M Sano and Y. Sawada, "Measurement of the Lyapunov spectrum from a chaotic time series", Phys. Rev. Left., vol. 55, no.10, pp. 1082-1085, 1985.
[11] N Ni Soe, M Nakagawa, "Chaotic Properties of Hemodynamic response in Functional Near Infrared Spectroscopic Measurement of Brain Activity ," Intl. Journal of Biological and Life Sciences, vol. 4; pp 34-43, 2008
[12] K Kamo, " Some phenomena before the summit eruptions at Sakura-zima volcano", Bull. Volcano'. Soc. Japan, vol. 23, pp 53-64 (Japanese with English abstract), 1978
[13] S Maryanto, M Iguchi, and T Tameguri, "Constraints on the sources mechanism of harmonic tremors based on seismological, ground deformation, and visual observations at Sakurajima Volcano, Japan," Journal of Volcanology and Geothermal Research, vol. 170, pp. 198-217, 2008
[14] T Tameguri, S Maryanto, and M Iguchi, "Moment tensor analysis of harmonic tremors at Sakurajima Volcano," Ann. Disast. Prey. Res. Inst. Kyoto University, vol. 48B, pp. 323-328, Apr. 2005.
[15] T Tameguri, S Maryanto, and M Iguchi, "Source Mechanism of Harmonic Tremor at Sakurajima Volcano," Bull. Volcanol. Soc. Japan, vol. 52, pp 273-279, 2007.
[16] B Chouet, "Excitation of a buried magmatic pipe: a seismic source model for volcanic tremor," J. Geophys. Res., vol. 90, no. B2, pp 1881-1893, Feb. 1985.
[17] BR Julian, "Volcanic tremor: non-linear excitation by fluid flow," J. Geophys. Res., vol. 99, no. B6, pp 11859-11877, Jun. 1994.