| Purpose Sakurajima Volcano research Center has conducted seismic observation and ground deformation measurement at Guntur volcano,and tilt observation at Merapi volcano collaborating with Volcanological Survey of Indonesia to study eruption mechanism of volcanoes in Java. Research Center of Earthquake Prediction has repeated GPS and gravity measurements in West Java with Bandung Institute of Technology to study tectonics of West Java. |
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| Observation network a Guntur Blue:Permanent seisnic stations,net:Leveling network,yellow:GPS benchmarks |
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| Merapi volcano Increase and decrease in tilt Were successively observed from the distant station to near stations to the summit. This suggests upward migration of pressure source from the magma pocket at depth of 2km to shallower part beneath the summit. |
Guntur Volcano Volcanic earthquakes occurred at depth of O-5km beneath the summit area and at depths of 5-1O km beneath Kamojang-Darajat geothermal area. The seismicity increase since May 1997 was accompanied with inflation around the summit crater. |
