Location: 11 km NNE of West Richland, Washington Period: 2 Apr 2009 22:07:02 - 16 Apr 2009 15:50:03 (13 days 17 hours 43 minutes) Volcanoes in 100km radius: None Earthquakes: 278 3 swarms found nearby. 2009 S20090308.1(1.2km) 7 Mar 23 days 2 hours 494 earthquakes S20090512.1(1.5km) 12 May 8 days 9 hours 221 earthquakes 2011 S20110904.1(1.6km) 4 Sep 3 days 13 hours 47 earthquakes