VOLCANO MADNESS: [Geology2] Fwd: Very strong (deep) earthquake below Sumatra, Indonesia – 12 year old boy killed by a collapsing house

Monday, September 5, 2011

[Geology2] Fwd: Very strong (deep) earthquake below Sumatra, Indonesia – 12 year old boy killed by a collapsing house

FYI

Begin forwarded message:

Earthquake overview : The very strong earthquake at intermediate depth happened below land on Sumatra, Indonesia
"I have Felt it" Reports –> see below + Let us know how you have felt this earthquake
To read the full story as it happened, we advise our readers to start at the lower part of the page (earthquake data).

Keep this page open as we will be back with more details when they become available

IMPORTANT update : METROTV Indonesia reports that a 12 year old boy has been killed by a collapsed house.
We advise people who understand Indonesian to follow the very good news updates from METROTV. Click here for the news bulletins of this station.

Update : MetroTV is talking about cracked houses (still dark in Indonesia).

Update : The quake was well felt in the following locations : Medan, Siantar, Langkat, Sibolga, Tana Karo and North Sumatra

Update : WAPMERR, the theoretical damage engine reports : USGS gives 119 km depth. A recent earthquake at similar depth generated high frequency waves that did more damage than expected in Padang. Thus, casualties are possible in this case, although not likely to be numerous. Here, we consider the worst case (map attached)

Update : It has been reported however in Singkil that people also fled from their homes thinking that a tsunami may come. However, there is no tsunami threat.

Update : Hundreds of patients were evacuated from 1 hospital in Medan. The area is said to have been also without power.

Update : It was felt for 30 seconds in the location of Dairi. Reports from Indonesian news sources say the tremor was alleged to have caused an electrical installation in the Dairi to become disrupted as residents experienced power outages. "It is pitch black". From ground level they also believe that there must be damage given the shock. It is the strongest earthquake that a lot of residents have ever felt according to them.

Update : Further reports indicate power outages in the epicentral area, but these reports still do not know of any collapsed houses or casualties.

Update : BMKG is reporting a Ml6.7 , with 78km depth at 2.81 N- 97.85 E. BMKG is the main Indonesian Geophysical centre (as well as meteorology).

Update : Reports from near the epicentre through Indonesian press show that the earthquake was felt very strongly, and people have left their homes in panic, however this was a lot due to the memory of the Indian Ocean Tsunami of 2004 in the same region.

Update : Strangely enough, very few CATDAT damaging earthquakes have occurred in this epicentral region historically. Generally they occur further offshore. The depth of the earthquake has meant that shaking is not as strong as expected. 1990 and 2005 had shocks within 150km.

Update : The 'I Have Felt It reports' we have received so far are coming from Malaysia + 1 from Medan, Indonesia

Update : The data below are weakening the earthquake to an important but probably minor dangerous quake. Let us hope it. It will take several hours before the situation in the inland hypocenter area will be clarified. We will of course update when more information becomes available.

Update : Data from other seismological agencies are confirming the deep hypocenter :
BMKG (Indonesia) : 6.7 @ 78 km
EMSC (Europe) : 6.6 @ 95 km
GFZ (Germany) : 6.6 @ 91 km
China : 6.6 @ 110 km
Australia : 6.6 @ 101 km

Update : We continuously try to reach the local Indonesian seismological website, but it hangs constantly (probably to many attemps to reach the website).

Update : The earthquake occurred at 00:55 AM and however deep, we feel that this earthquake is strong enough to create (minor) damage and injuries.

Update : It is very normal that people in Malaysia and Thailand will have felt this earthquake as the' shaking is generated by the combination of the deep hypocenter and the magnitude.

Update : Even with this deep hypocenter, USGS still predicts a MMI VI, strong shaking in a wide area around the epicenter.

IMPORTANT Update : USGS has recalculated its data and comes now with a magnitude of 6.6 (earlier 6.5) and the good news is a far deeper hypocenter at 110 km (instead of 52 km earlier on). The new epicenter location is luckily in a wilderness area at approx. 20 km from Siempat Nempu Hilir.

Update : USGS pager is giving only a very slight probability of injured and damage. All will depend on the precise depth of the earthquake.

Update : the villages closest to the epicenter are : Kluet Selatan, Bakongan and Trumon. The epicenter is approx. 15 km from the coast. A tsunami is not likely as the magnitude is limited and the epicenter is below land (if the preliminary data are correct).

Update : the earthquake is felt as far as Thailand

Update : A V moderate MMI (moderate shaking is reported from Banda Aceh

Update : The earthquake was even felt at Penang, Malaysia

M 6.5 2011/09/05 17:55 Depth 52.3 km NORTHERN SUMATRA, INDONESIA
September 06, 2011 at 12:55:09 AM at epicenter
130 km (81 miles) SW (236°) from Medan, Sumatra, Indonesia
Satellite map of the greater epicenter area

"I Have Felt It" reports as received by Earthquake-Report.com
MMI values (if indicated) after the text (III: Weak shaking, IV Light shaking, V Moderate shaking, VI Strong shaking, VII Very Strong shaking)
- We have a report coming in from Medan stating a Strong shaking
- Another report from Malaysia that people there felt a weak shaking
- Kajang, Malaysia : at about 2:00 AM (Malaysian Time)6th September 2011 we felt the building shaking from the 7th floor (weak shaking indicated)
- Sitiawan Perak, Malaysia : MMI III (weak shaking indicated)
- Kuala Lumpur, Malaysia : Was actually in the living hall, working on my assignment until i felt the building is slightly shaking for about 1-2 mins.

Most important Earthquake Data:
Magnitude : ~~6.5~~ 6.6
UTC Time : Monday, September 05, 2011 at 17:55:13 UTC
Local time at epicenter : Tuesday, September 06, 2011 at 12:55:13 AM at epicenter
Depth (Hypocenter) : ~~52 km~~ 110 km
Geo-location(s) :
Very close to Kluet Selatan, Bakongan and Trumon
100 km (62 miles) SW of Medan, Sumatra, Indonesia