Shake, Rattle, and Roll

Late Saturday night I had been reading up on the magnitude 4.7 earthquake and subsequent aftershocks that happened in Oklahoma during the early morning hours of the same day. Besides freaking out a lot of people, knocking over items on shelves, and causing very minor structural damage (a few cracks here and there) there was no major harm done. About a half hour later I was looking through Twitter and saw "Earthquake in Oklahoma" trending, and I was curious since I hadn't seen that trend earlier in the day. I looked at the tweets and realized that another earthquake had struck Oklahoma, this one much stronger at a preliminary magnitude of 5.2. The magnitude has since been upgraded to 5.6, making it the strongest recorded earthquake in Oklahoma. I first thought, "Oh snap! That is starting to get up there in terms of strength. And with minor damage that hasn't been repaired...." So far I'm reading in newspaper articles that there are no reports of major structural damage or major injuries. A county road did buckle, but overall it appears that Oklahoma has emerged unscathed.

Even before the magnitude 5.6 earthquake hit, there was a lot of talk about the earthquakes in Oklahoma, because they don't happen very often. The magnitude 5.8 earthquake that hit Virginia back in August was felt up and down the east coast. Here in NJ a lot of my friends felt it; my mom was laying in the sand at the beach; and I was so disappointed that I didn't feel it! I think I was engrossed with playing StarCraft at the time. It reminded evenyone again, that yes, earthquakes are possible on the East Coast. I remember the excitement that ensued after a magnitude 3.0 earthquake was epicentered in NJ in February 2009. A lot of people didn't even realize that earthquakes were possible in NJ, and funnily enough, about a week prior to the earthquake, I had decided to do my projects for school about earthquakes in NJ (I'll follow up with another post on that project).

The article I read mentioned that additional seismographs had been installed in the area due to an increase in the number of earthquakes occurring there. On average, the area gets 50 earthquakes, but last year, there were a little over 1,000 earthquakes recorded, which I found very interesting. Many people thought that there was an increase in large earthquakes worldwide following the devastating earthquakes in Indonesia in 2004, China in 2008, Haiti in 2010, and Chile in 2010.

On a side note- while I haven't experienced any of the earthquakes epicentered in NJ or the VA earthquake earlier this year, I did experience the magnitude 7.0 earthquake that struck Haiti in 2010. I was staying on the island of St. John in the US Virgin Islands, doing research for one of my classes. It was right before dinner, and I saw Jamie, who is one of the directors of the camp I was staying at, stop on the stairs coming out of his office. He said "Do you guys feel that?" and looked around at us, not moving from his spot on the stairs. We said no, and Jamie replied "I think it's an earthquake." At this point, I was hearing a low rumbling noise, however I didn't feel any shaking (I was sitting on a picnic bench) so  I crouched down and put my hand on the ground. I still didn't feel anything, and Jamie then told us it had stopped. I was curious to see if we had in fact just experienced an earthquake and if so, where the epicenter was. After dinner I did a Google search on my phone for recent earthquakes, and I was shocked when I saw the most recent earthquake. I went to Jamie and asked him roughly how long ago the shaking and rumbling had occurred. He said it happened about 20 minutes prior, so I replied. "Oh, ok, so what you felt was an earthquake. Twenty minutes ago a magnitude 7.0 hit..... in Haiti." We just stared at each other, flabbergasted. Over the course of the next few hours, I was glued to my phone for updates on the earthquake, and the reports were rolling in about the damage, and we were all so shocked and saddened. I was so amazed that we had felt and heard the effects of an earthquake that was epicentered 500 miles away.

Point A shows the location of Port-au-Prince, Haiti, near the epicenter of the January 12, 2010 earthquake. Point B shows where I was when the earthquake happened. Despite being 500 miles away, I heard the ground rumble and others felt slight shaking of the ground.

So back to the public's perceived increase in earthquakes.... The earthquake in Haiti received a lot of attention, given the widespread destruction and loss of life. When an even stronger earthquake hit Chile, it was only natural that it received a lot of media attention. Times have changed- people didn't find out about the explosion of Krakatoa right away, if they heard about it at all. In my own experience, it seems I get braking news first on Facebook or Twitter, because information is spread and shared so easily and rapidly. According to the United States Geological Survey, there is no increase in earthquakes with a magnitude 7.0 or more, however, there has been an increase in the number of detectable earthquakes. This is due to increased sensitivity of the instruments used, and an increase in the number of instruments.