From a geologist's perspective it's pretty routine, actually. Had an earthquake nearby of almost the same magnitude in 1952, which in term of geology is seconds ago.
And central Oklahoma has clear seismic hazard shown on USGS seismic hazard maps.
USGS upgrades latest earthquake to 5.6; strongest on record in Oklahoma
Posted: 11:27 PM
Last Updated: 2 minutes ago
TULSA - The U.S. Geological Survey is reporting that the latest in a series of earthquakes in Oklahoma is the strongest on record for the state.
According to the USGS , the earthquake that struck at 10:53 p.m. Saturday has been upgraded to a magnitude 5.6. The epicenter is four miles east of Sparks, Okla. in Lincoln County, 21 miles northeast of Shawnee.
Lincoln County Emergency Management is reporting significant damage.
Tremors were felt as far east as Little Rock and as far north as Wichita.
The earthquake broke the record set in 1952 in El Reno. That quake was recorded as a 5.5.
The latest comes after a shocking 4.8 earthquake that occurred in the early morning hours Saturday near Prague, Okla.
Aftershocks were felt for hours following Saturday’s first quake, which Amie Gibson, a research scientist for the Oklahoma Geological Survey, said was the strongest to hit the state in nearly sixty years.
That is, until this most recent quake.
Gibson said Saturday that aftershocks from the first earthquake could occur for days.
Read more: http://www.kjrh.com/dpp/news/local_news/strong-5.2-earthquake-rattles-oklahoma#ixzz1ctl0JsDo
The gist of what I’m reading is that the recent surge in activity in Oklahoma is statistically significant but not unexpected. Geologically, I don’t doubt 1952 was mere moments ago, but we don’t get a lot of earthquakes like this in Oklahoma. Perhaps abnormal is the incorrect word for it. A 5.6 is normal activity, but it’s relatively rare to have 5.6 quakes in Oklahoma, right?