• At 12.00 – 18.00 hours (local time), there have been 8 times long tectonic quake occurred with max amplitude 2-7 mm, long quake of 55 – 125 second. A time local tectonic quake, amplitude 48 mm, S-P 6 second, long quake of 35 second. 4 times deep volcanic quake (VA), max amplitude 6-38 mm, S-P 0.5 second and long quake of 7.5 - 20 second. 7 times shallow volcanic quake (VB), max amplitude 4-5 mm, long quake of 2.5 - 5 second.

• At 18.00 – 24.00 hours (local time), there have been twice long tectonic quake occurred with max amplitude 3-8 mm, S-P 23, long quake of 45 – 50 second. A time local tectonic quake, amplitude 46 mm, S-P 0.5 second, long quake of 20 second. 7 times shallow volcanic quake (VB), max amplitude 4-5 mm, long quake of 2.5 – 4 second. Tremor quake at 18.14 – 24.00 hours with max amplitude 0.5 – 1 mm.

B. 31 May 2009
• At 00.00 – 06.00 hours (local time), there is 2 long tectonic quakes occurred with max amplitude 3-24 mm, long of quake 100 – 175 second. 1 time local tectonic, amplitude 51 mm, S-P 6 second and long of quake 85 second. 3 times deep volcanic quake (VA), max amplitude 10-28 mm, S-P 0.5 second, long of quake 10-15 second. 9 times shallow volcanic quake (VB), max amplitude 3-5 mm, long of quake 3-7.5 second. Tremor quake began at 00.00 – 05.15 hours with max amplitude 0.5-1 mm.

• At 06.00 – 12.00 hours (local time), a tectonic quake, it felt 1 MMI at 07.01 (local time), a time tectonic quake, it felt 2 MMI at 11:35 (local time), 41 times local tectonic quake, max amplitude 22 – 50 SP 6.5 second with long of quake 15 – 30 second. 61 times deep volcanic quake (VA), max amplitude 9 – 27mm, S-P 0.5 – 1 second, long of quake 5 – 10 second. 56 times shallow volcanic quake (VB), max amplitude 4 – 6 mm, long of quake 5 second. Volcano tremor quake continually happened, max amplitude 51 mm over-scales.

2. Vision
A. 30 May 2009
• At 00.00 – 06.00 hours (local time), bright weather. Steady wind blew. White medium-thin smoke on caldera I, 25 meters high. Blazing lighting has vision on 10 meters high.  
• At 06.00 – 12.00 hours (local time), bright weather. Steady wind blew. White medium-thin smoke on caldera I, 10-50 meters high. Thin white smoke on caldera II with the high 25 meters.
• At 12.00 – 18.00 hours (local time), bright weather. Steady wind blew. White medium-thin smoke on caldera I, 10-50 meters high. Thin white smoke on caldera II with the high 25 meters
• At 18.00 – 24.00 hours (local time), bright weather. Steady wind blew. White medium-thin smoke on caldera I, 10-25 meters high. Thin white smoke on caldera II with the high 25 meters, Blazing lighting has vision on 25 meters high.  
  
B. 31 May 2009
• At 00.00 – 06.00 hours (local time), bright weather. Steady wind blew. White medium-thin smoke on caldera I, 10-50 meters high. White thin smoke on caldera II with the high smoke is 25 meters. Blazing lighting has vision on 10 meters high.  
• At 06.00 – 12.00 hours (local time), bright water, steady wind blew, white – medium thin smoke on caldera I, its diameter 25 meters. Since 06.30 hours (local time) it had been vision thick smoke on main caldera, having white-brown color with the high of its diameters 100 meters from the summit. At 08.24 hours (local time) lava fall has continually occurred slides to the south entering Kali Batuawang over the distance of diameters 2250 m from the summit, entering Kali Kahetang and Kali Keting until the distance of diameters 1500 from summit. Its lava slides fall has also observed entering Kali Nanitu and Batang till the distance of diameters 1000 m from summit. At 08.28 hour (local time), dark-blue brown of thick smoke has blew continually with the high diameters 25 – 700 meters following with thundering in low-medium intensity. 

4. Synopsis 
• The increasing of Mt Karangetang activity since on the date of 31 May 2009 that indicated by; Increasing of volcanic tremor quake, blowing smoke that continually happen and fallen blazing lava followed by thundering sound with maximum slide distance 2250 meters, dominantly heading to the south.
• Based on visual and the result of quake observation, so, effective on 31 May 2009 at 13.00 hours (local time), the status of Mt. Karangetang that previously was 3rd stage / Orange alert, will be altered to 4th Stage / Red Alert.
In relation to that alteration status, so, the Center of Volcanology and Mitigation Disaster Geology (PVMBG) will keep observing and assign Emergency Response Team to conduct and evaluate the activity of Mt. Karangetang. Its alteration status has been informed to Sitaro Regent via post of Karangetang observatory.
An intensive observation is still take place to evaluate of Mt. Karangetang and we keep coordination with certain local government (The Executive Region of Preventive Disaster).

4. Recommendations  
In relating to Red Alert status, so we recommended :
a. Local government wish to take necessary evacuate steps to prevent local people from the threat of pyroclastic fall and the threw of blazing lava, especially for the people who live around as follows;
• Subdistrict of Siau Timur in “Kola-Kola” village (Bebali village); villagers who live in Bolo and Kopi village which in the coverage of Tarorane subresidence area, people who live in Hekang village which in the coverage of Tatahadeng subresidence area, people in the village, upper side of Dame 1, and the people around the slope Kali Beha Timur at karalung village. 
• Subdistrict Siau Tengah, those who live in Dompase village.
• Subdistrict Siau Barat Utara, they those who live in the side of Kali Nanitu and kali Kinali
b. Strongly advise people to stay away the volcano of Karangetang within diameters of 3000 meters away from such main eruption.
c. If the rain ash comes heavily, it is requested to wear dust mask since the volcanic ash is dangerous for health and causing respiratory disease.
d. Request to the people who live around Mount karangetang to stay calm, not to provoke by any Irresponsible issued about this mountain. The Center of Volcanology and Mitigation Geology Disaster (PVMBG) will keep coordination with Province Government of North Sulawesi (The Executive Prevention of Region Disaster), together with the Regency of Sitaro about Mount Karangetang activity. Advise people to follow to what government addressed.
e. The Region Government will always keep coordinating with the post of Karangetang observatory at Salili village, subdistrict Siau Tengah, Sitaro regency or with the Center of Volcanolgy and Mitigation Geology Disaster (PVMBG) in Bandung.

Source : http.//vsi.esdm.go.id
Translated by VAI team