BANDUNG. The Center for Volcanology and Geological Hazard Mitigation (PVMBG) Geological Agency, MEMR commecning from December 18th 2011 at 4 a.m. increased the status of Mt. Ijen from Advisory (Level II) to Watch (Level III). Citizens surrounding Mt. Ijen and visitors/tourism/hikers/miners are not alllowed to get close to the crater in the peak of Mt. Ijen within the radius 1, 5 km from the active crater.
“Based on visual and seismic observation and also data analysis, so commencing on December 18th, 2011 at 4 a.m. the activity status of Mt. Ijen increased from Advisory (Level II) to Watch (Level III),” says Surono.
Related to the increased status, PVMBG will increase observation intensively to evaluate the activity of Mt. Ijen and coordinate with local BPBD. Mt. Ijen is an active volcano having Crater Lake in the peak with 800 m length, 700 m width, and 180 m depth. Geographically, Mt. Ijen is located in the position of 8º 03’ 30” South Lat. and 114º 14’ 30” West Long., with its peak 2386 m above the sea level (asl). Administratively is located in two districts; Bondowoso and Banyuwangi, East Java province. Mt. Ijen eruption recorded in the history was phreatic explosion coming from the Crater Lake. The last phreatic eruption happened in 1993 producing high black ash, which reached 1000 m height. Since December 15th, 2011 the activity of Mt. Ijen increased from Normal (Level I) to Advisory (Level II) based on its seismic activity increase.
Since October – December 14th, 2011 the volcanic activity increase of M. Ijen was designated by the volcanic activity increase both visual, its number of monthly deep volcanic earthquake (VA), shallow volcanic (VD) and continuous tremor earthquake. Since 5th – 14th of December 2011 the volcanic activity increase was followed by harmonic tremor earthquake, which designated the activity near the surface under the Crater Lake becoming more intensive. Within the period of December 15th – 17th, 2011 there had been activity increase significantly, which was designated by sharply number of deep volcanic earthquake and shallow volcanic earthquake and also followed by the strengthening of SO2 gas surrounding Crater Lake of Mt. Ijen
The period of December 15th – 17th 2011 there had been activity increase significantly, which was designated by sharply number of deep volcanic earthquake and shallow volcanic earthquake and also followed by the strengthening of SO2 gas surrounding Crater Lake of Mt. Ijen
The visual observation of the Crater Lake on December 17th, 2011 showed the color of the lake changed from light green whitish to white. The smell of sulfur gas surrounding the crater became stronger and the water temperature measurement of the Crater Lake becoming difficult to do without wearing mask.
The eruption danger potency of Mt. Ijen in Disaster-Prone Area III is surrounding the Crater Lake. It is threatened by poisonous gas flow, pyroclastic flow, hot mud, lava, heavy ash rain, and explosion lava. The Disaster-Prone Area II is the potency of pyroclastic flow, explosion lava, rain lava, heavy ash rain, and possibly volcanic landslide and incandescent material flow.
The Disaster-Prone Area I is lava rain flow, pyroclastic expansion or explosion lava, heavy ash rain, and possibly affected by incandescent material flow. The head of PVMBG asked citizens surrounding Mt. Ijen to be calm and not influenced by issue of Mt. Ijen explosion and not to get close to the crater in the peak of Mt. Ijen within the radius 1, 5 km from active crater. For citizens live in surrounding Mt. Ijen within KRB II to be always alert and pay attention to the progress of Mt. Ijen activity issued by local BPBD.
“Citizens live along Banyuputih River, up streaming in Crater Lake Ijen have to be alert to the possibility of Crater Lake Ijen overflow if explosion happens,” says Surono. (AK)
