Location: 4 km NE of Greenbrier, Arkansas Period: 16 Feb 2011 09:30:13 - 19 Feb 2011 04:51:36 (2 days 19 hours 21 minutes) Volcanoes in 100km radius: None Earthquakes: 68 5 swarms found nearby. 2010 S20101120.1(5.3km) 19 Nov 6 days 8 hours 103 earthquakes S20101206.1(7.6km) 5 Dec 5 days 2 hours 47 earthquakes 2011 S20110221.1(1.7km) 20 Feb 2 days 16 hours 43 earthquakes S20110228.1(1.2km) 28 Feb 4 days 7 hours 79 earthquakes S20110408.1(2.5km) 7 Apr 3 days 0 hours 54 earthquakes