a magnitude 3.6 earthquake near rancho cucamonga san bernardino county california usa was reported by the united states geological survey considered the key international and national agency that monitors seismic activity in the us the earthquake occurred at a very shallow depth of three miles beneath the epicenter early morning on wednesday december 8 2021 at 2 28 am local time our monitoring service identified a second report from the european mediterranean seismological center emsc which listed the quake at magnitude 3.6 as well weak shaking might have been felt in lytle creek located four miles from the epicenter rancho cucamonga 8 miles away fontana 9 miles away rialto 10 miles away and upland 11 miles away other towns are cities near the epicenter where the quake might have been felt as very weak shaking include ontario located 13 miles from the epicenter san bernardino 14 miles away pomona 17 miles away in anaheim 35 miles away