Location: 1km WSW of Pleasant Hill, CA Period: 15 Oct 2019 05:01:02 - 16 Oct 2019 07:04:26 (1 day 2 hours 3 minutes) Volcanoes in 100km radius: None Earthquakes: 52 7 swarms found nearby. 2003 S20031011.1(6.3km) 11 Oct 1 day 21 hours 35 earthquakes 2007 S20070302.1(5.6km) 1 Mar 1 day 23 hours 32 earthquakes 2009 S20090609.1(3.7km) 8 Jun 2 days 7 hours 44 earthquakes S20090728.1(7.8km) 27 Jul 12 hours 24 earthquakes 2015 S20151014.2(14.0km) 13 Oct 21 days 18 hours 617 earthquakes 2018 S20180223.1(8.8km) 22 Feb 2 days 9 hours 38 earthquakes 2021 S20211117.1(13.1km) 17 Nov 18 hours 32 earthquakes