HOUGHTON -- Amid all the horrific reports and video coming from Japan after the massive earthquake a few days ago, some of us have wondered, "What about here?  Could we see a devastating earthquake in the U.P.?"

The answer, quite simply, is no.

"The Great Lakes are just about the safest place you can live in North America as far as earthquakes are concerned," says Michigan Tech seismologist Dr. Wayne Pennington.

There have been occasional minor earthquakes in the lower Great Lakes, but nothing significant because there's not much seismic activity here.

"The crust that comprises the earth beneath the Great Lakes," Pennington says, "is among the oldest on earth and is very stable."

As for that bizarre crack that opened up in Menominee County last year, Pennington says that was just a layer of limestone beneath the clay and soil that suddenly buckled and popped up.  Why?  It's not certain, but it's likely it was the delayed result of glaciers retreating from the Great Lakes more than 10,000 years ago.

What about tsunamis on the Great Lakes?  No serious worries there either, although Pennington says a landslide on one side of a lake could cause a substantial wave on a nearby coast.

More common is a seiche, which is a wave caused by certain atmospheric conditions--high pressure on one side of the lake, low pressure on the other.

"It's like water sloshing from one side of the bathtub to the other," Pennington explains.

It's not anything close to the magnitude of a tsunami, he says, but people with docks on the lake will notice the change:  the water level might rise or drop a few feet within a very short time because of the seiche.