The quake settled down (?)

Update (May 22 evening): no aftershock ober 4.0 since yesterday. It seems that the quake has really passed, when the nation mourned.

Update: seems it is settling down slower than I have thought.
(and USGS seemed to have been adjusting its calculations, both in terms of quake strength and coordinate. This is no surprising given the distance away and the complication of earth crust structure on the path

The last aftershock with strength over 4.0 was recorded at 21:01:07 (5.1) UTC on May 14, i.e. 05:01:07 Beijing Time 15th May. It has been more than 5 hours since then by now.

There were 10 such aftershocks in the 24 hours before that.

The total number of quakes over 4.0 since May 12 are

  • May 12th: 29
  • May 13th: 10
  • May 14th: 11
  • May 15th: 5
  • May 16th: 6
  • May 17th: 2
  • May 18th: 3
  • May 19th3
  • May 20th: 1
  • May 21st: 0
All aftershocks are still located on the NE-SW running strip from Wolong to the border of Sichuan and Gansu near Pingwu County (平武).

The list of aftershocks are as below (source: USGS) , and mapped above. Note that there has NOT been any aftershock (above 4.0) to the south or west of the 1st (7.9 grade) quake, which seems to indicate that the 1st quake was the beginning point of fault line, and perhaps the fault line has "extended to the SW" a bit after this quake.

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