My first thought was an extreme gust of wind had struck our house. We have plenty of those. The house had stopped vibrating by the time I stepped over to the window and looked outside. I realized suddenly it was an earthquake.
In Oklahoma? Really? Actually we do have earthquakes, historically about as many per year as tornadoes, but they are usually minor with no consequences. This one was a bit larger, a 5.6 and the largest ever recorded in Oklahoma. It occurred about bedtime Saturday night and followed a 4.7 one early Saturday morning that we slept through, same as with the 4.0 aftershock this morning. Fortunately, the damage in the state was minor.
Lately, over the last year of so, we've experienced an increase in the number of earthquakes occurring each year, going from about 50 per year to over 1000. Some say the increase is due to the rise in the use of subsurface fracturing to exploit natural gas reservoirs. I've been telling everyone it's caused by global warming and the melting of glacier ice deposits. Hey, ice is heavy, and we're losing deposits that are thousands of feet thick.
Maybe we're just due for a tectonic correction. Or maybe God is angry with Oklahoma.
The earthquake epicenter was about 50 miles west of here and three miles down. It likely occurred along an ancient faultline; there's one in the area. Most of Oklahoma's 'quakes occur in that same area. Many small earthquakes are preferred. That prevents the stress from building to cause a large one.
Oceanography and Geology. Sounds like you will have an interesting, but busy semester with lots of field trips.