A 2.8 magnitude earthquake struck the northeast Arkansas town of Trumann at 12:20 a.m. Tuesday. It's the latest in a series of seismic events occurring over the last several months near the New Madrid Seismic Zone.
Scott Ausbrooks, the Geohazards Supervisor with the Arkansas Geological Survey, says that although the magnitude was not severe, even small increases in magnitude results in an exponential release of energy. Ausbrooks says,
A really great way to think about it is that for every magnitude you go up there's thirty two times more energy released. You go from a magnitude 2.7 to a magnitude 4.7, which is about the threshold when you can start getting a little bit of damage, there's 900 times more energy released in a 4.7 versus a 2.7.
Minor earthquakes are a regular occurrence near the New Madrid Fault. Ausbrooks says,
No explanation for it other than we're just going to say that this is part of the natural cycle. Earthquakes go through periods of coessence, just calm, and then you get these bursts of activity. They're, episodic is the word we use.
Several natural gas pipelines pass through the region but Ausbrooks says that Tuesday's quake was likely not strong enough to cause any damage.
Although this earthquake is not necessarily a warning sign, this area of northeastern Arkansas has historically experienced severe earthquakes. Most notable is the New Madrid Earthquake of 1811 which ranks as one of the twentieth largest earthquakes in recorded history.