Earthquake in Georgia 4-26-13 USGS

The prehistoric North American shoreline at the Craton Boundary was active the week of April 21 – 27, 2013. Oklahoma, Texas, and Georgia were rattled by small earthquakes, yet quakes in these states are not common. Oklahoma had 6 earthquakes during the week, while the Texas Panhandle and Northeastern Georgia had 2.8 magnitude quakes within 3 minutes of one another.

Earthquakes in Texas and Oklahoma 4-26-13 USGS

The Craton

Here’s a Cliff Note’s version about Cratons:  the continents that we “see” today have not always been the continents “seen” in the past – before humans.

The continents that we live upon are the archeological remnants of ancient continents, and are terrestrial artifacts formed from the fragments of the breakup of older supercontinents, long extinct. Over the past 500 million years, there have been five different sets of continents, called supercontinents. Sometime in the future, there will be a sixth supercontinent very different from what we know today.

The Craton boundaries are found all over the Earth because these are the ancient continental boundaries that we can “no longer see.” But, they are still there, and are becoming more active as the Earth’s poles shift and reposition the planet’s crust.

The North American Craton runs alongside/parallel to the Appalachian Mountains and turns west in Northern Georgia. It goes through Northern Alabama, Mississippi, Southern Arkansas and Oklahoma, and Northern Texas. At the foothills of the Rockies in Northeastern New Mexico, the Craton boundary shoots north and parallel to the Rocky Mountains through Canada.

More Earthquake Activity

In the future, more earthquake activity will be felt between the Appalachian and Rocky mountain ranges in the lower coastline states. This ancient crust is less dense and more unified than the denser mountainous areas on the North American Plate, so as the Earth shifts, this crust will shift differently from the weaker parts of the Earth.

Here’s a suggestion for those living in the Southern USA: over the next few months, you might want to secure your grandmother’s china poised in the antique china cabinet.