well, roadsds buckled,le cracks open ed up in homesom and bottles fell from store shelves. the most powerful
earthquake to ever strike oklahoma was feltlael by people from wisconsin to here in n north texas. the magnitude 5.6 qua6ke struck around 11:00 last night ne1:ar theas city of spar ks. that is about 40 miles east of mi ea oklahoma city.it wewe are going to speak with anit earth and sc ienceea professor on the phone right now. good morning to you.or >> good morning. >> the >>5.6 quake not huge, but thee effects were really felt fwidespread. why could people from so many s differentt areas feel this? >> here in the mid continental united states, we have a lot of very old rock, and because the ec rock is very old, it's very hard. and the seismic velocities are relatively higher than some earth or softer rocks maybe out west that are slightly hotter. and that way the seismic waves can propagate over a long area, a wide area. >> it seems like we are having more of these in this part of the country that's supposed to be more stable from a siez nick standpoint.st is there anythingny driving that, or is this just sort of a pattern? >> well, it's not -- it's not that clear. and it's not that clear to me that there's any significant fi increase yet in the number y of
earthquakes either.ei i mean, you know, we don't have very much m
earthquakes here in the mid continent, as you poi ynt out, because this is not an area that's near a ate boundary. the fact that there were a number of events located very close to where this larger l event, the 5.6, occurred last night in the days preceding this event is kind of interesting. i mean, maybe those werese sort of precursory events or foreshocks sometimes as seismologists call them. these events, there's a serieser of faults that are ancient structures that are mapped by the oklahoma and u.s. geological survey through this region that aree trending to the northwest, t, but these are verye ancient structures, and they are in the deep basement rocks of that t s region. so it's possible that these faults are being reactivated. and i understand that there's potentiallyia some reinjection of water that's been b used ind the hydro fracking processng that's been used in this region, but i don't know much about thknat. >> professor, thank you for your insight this morning. we a.ppreciate it.