There have been some reports of a magnitude 6.1 earthquake shaking things up in eastern Indonesia. More info from the USGS:
The media report that there was a tsunami warning issued, which seemed a little odd: you’re not going to get a surface rupture from a quake this deep (it must be within a subducting plate), although there’s possibly a risk of triggering an undersea landslide in this area. If you wander over to the NOAA Tsunami Warning Center, though, the text of the bulletin they issued 15 minutes after the earthquake states::
NO DESTRUCTIVE WIDESPREAD TSUNAMI THREAT EXISTS BASED ON
HISTORICAL EARTHQUAKE AND TSUNAMI DATA.
Calling this a ‘warning’ strikes me as a bit of an exaggeration.
A few hours before this, there was also a magnitude 6.6 earthquake in western Indonesia, which doesn’t seem to have got much media attention even though it should have shaken up a few people in Banda Aceh:
If that place sounds familiar, it should. This was a shallow thrust earthquake close to the Sunda Trench, the convergent plate boundary which generated the Boxing Day 2004 earthquake and tsunami (the epicentre of that quake was located on the very bottom right of the inset map). This part of the trench is part of the section that ruptured in 2004, so it seems unlikely that this earthquake occurred on the subduction thrust itself – the elastic strain built up by just two-and-a-half years of plate convergence just isn’t enough to produce an earthquake this powerful. Most likely it was a thrust in the accretionary wedge, and, from a first glance, much more likely to generate a tsunami, even though it didn’t seem to trigger any sort of bulletin at all. Curious…
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