ANALYSIS OF GRAVITY ON ALTITUDE CHANGES IN GRAVITY MICRO DATA USING POLYNOMIAL EQUATION APPROACH (CASE STUDIES OF MERAPI AND KELUD VOLCANOES)
Keywords:Gravity changes, altitude changes, infinity slab, spherical effect, coefficient of determination
AbstractAnalysis of gravity changes to altitude changes from gravity measurements at Merapi Volcano and Kelud Volcano was carried out to determine the characteristics of the two mountains based on the gravity method. Merapi Volcano and Kelud Volcano are two very active mountains in Indonesia and have different physiography, especially at the top of Kelud there is a crater filled with water. Repeated gravity surveys will be useful for studying deformation in volcanoes and providing information about changes in subsurface mass. The gravity data on Merapi Volcano is secondary data from BPPTKG (Research and Development Center for Geological Disaster Technology), and data on Kelud Volcano is obtained from the 2019 data collection survey. Volcanic monitoring using the gravity method is carried out by observing changes in gravity with changes in altitude to study deformation in the volcano and providing information about changes in subsurface mass using a polynomial equation approach of to . The findings indicate that there was little variation in the gravity anomaly within Merapi Volcano between 2018 and 2019. The highest coefficient of determination, at 96%, was observed in the gravity anomaly data from inside the Kelud Volcano in 2019, after applying Bouguer corrections in the form of spherical effects. Additionally, the coefficients of the second and third order polynomials of the Merapi Volcano data had opposite signs to those of Kelud Volcano, suggesting that the internal source of the gravity anomaly within Merapi Volcano is distinct from that within Kelud Volcano.
B. Voight, E. Constantine, S. Siswowidjoyo, and R. Torley. 2000. Historical Eruptions of Merapi Volcano, Central Java, Indonesia, 1768–1998. Journal of Volcanology and Geothermal Research. 100: 69-138. Doi: 10.1016/S0377-0273(00)00134-7.
M. R. Dove. 2008. Perception of Volcanic Eruption as Agent of Change on Merapi Volcano, Central Java. Journal of Volcanology and Geothermal Research. 172(3): 329-337. Doi: 10.1016/j.jvolgeores.2007.12.037.
R. Scandone, K. V. Cashman, and S. D. Malone. 2007. Magma Supply, Magma Ascent and the Style of Volcanic Eruptions. Earth and Planetary Science Letters. 253(3): 513-529. Doi: 10.1016/j.epsl.2006.11.016.
J. W. Esson. 1982. Geodesy (4th edn) by G. Bomford. Clarendon Press, Oxford. Geological Journal. 17(1): 66-67. Doi: 10.1002/gj.3350170108.
W. M. Telford, W. M. Telford, L. P. Geldart, R. E. Sheriff, and R. E. Sheriff. 1990. Applied Geophysics. Cambridge University Press.
D. L. Turcotte and G. Schubert. 2002. Geodynamics. 2nd Edition. Cambridge University Press.
D. Dzurisin. 2006. Volcano Deformation. Berlin, Heidelberg: Springer Berlin Heidelberg. Doi: 10.1007/978-3-540-49302-0.
P. Jousset, S. Dwipa, F. Beauducel, T. Duquesnoy, and M. Diament. 2000. Temporal Gravity at Merapi during the 1993–1995 Crisis: An Insight into the Dynamical Behaviour of Volcanoes. Journal of Volcanology and Geothermal Research. 100(1): 289-320. Doi: 10.1016/S0377-0273(00)00141-4.
D. Dzurisin. 2006. Volcano Deformation. Berlin, Heidelberg: Springer. Doi: 10.1007/978-3-540-49302-0.
A. Ratdomopurbo and G. Poupinet. 2000. An Overview of the Seismicity of Merapi Volcano (Java, Indonesia), 1983–1994. Journal of Volcanology and Geothermal Research, 100(1): 193-214. Doi: 10.1016/S0377-0273(00)00137-2.
A. Saepuloh, K. Koike, M. Omura, M. Iguchi, and A. Setiawan. 2010. SAR- and Gravity Change-based Characterization of the Distribution Pattern of Pyroclastic Flow Deposits at Mt. Merapi during the Past 10 years. Bull Volcanol. 72(2): 221-232. Doi: 10.1007/s00445-009-0310-x.
C. Tiede, A. G. Camacho, C. Gerstenecker, J. Fernández, and I. Suyanto. 2005. Modeling the Density at Merapi Volcano Area, Indonesia, via the Inverse Gravimetric Problem. Geochemistry, Geophysics, Geosystems. 6(9). Doi: 10.1029/2005GC000986.
Blake, D. M., Wilson, G., Stewart, C., Craig, H. M., Hayes, J. L., Jenkins, S. F., Wilson, T. M., Horwell, C. J., Andreastuti, S., Daniswara, R., Ferdiwijaya, D., Leonard, G. S., Hendrasto, M. and Cronin, S. 2015. The 2014 Eruption of Kelud Volcano, Indonesia: Impacts on Infrastructure, Utilities, Agriculture and Health. GNS Science Report 2015/15.
L. R. Goode, H. K. Handley, S. J. Cronin, and M. Abdurrachman. 2019. Insights into Eruption Dynamics from the 2014 Pyroclastic Deposits of Kelut Volcano, Java, Indonesia, and Implications for Future Hazards. Journal of Volcanology and Geothermal Research. 382: 6-23. Doi: 10.1016/j.jvolgeores.2018.02.005.
S. Hidayati et al. 2019. Differences in the Seismicity Preceding the 2007 and 2014 Eruptions of Kelud Volcano, Indonesia. Journal of Volcanology and Geothermal Research. 382: 50-67. Doi: 10.1016/j.jvolgeores.2018.10.017.
U. Sumotarto. 2018. Geothermal Energy Potential of Arjuno and Welirang Volcanoes Area, East Java, Indonesia. International Journal of Renewable Energy Research (IJRER). 8(1): Art. no. 1.
M. F. Kane. 1962. A Comprehensive System of Terrain Corrections using a Digital Computer. Geophysics. 27(4): 455-462. Doi: 10.1190/1.1439044.
D. Nagy. 1966. The Prism Method for Terrain Corrections using Digital Computers. PAGEOPH. 63(1): 31-39. Doi: 10.1007/BF00875156.
G. Williams-Jones and H. Rymer. 2002. Detecting Volcanic Eruption Precursors: A New Method using Gravity and Deformation Measurements. Journal of Volcanology and Geothermal Research. 113. Doi: 10.1016/S0377-0273(01)00272-4.
BPPTKG. 2018. Karakteristik Gunung Merapi. URL (accessed 11.13.19).
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