The geological activity starts on the U.S. west coast and works its way to the U.S. midwest. The plates are stopping all over the world, but for some reason only the U.S. is affected. Go figure. At one point in the movie they stated that a huge rift is opening in the ground at Mount Rushmore, except the red dot they showed on the map was nowhere near Mount Rushmore. The red dot was in the middle of South Dakota. Mount Rushmore is not in the middle of South Dakota.
The rift moved south at a huge rate of speed, working toward the Gulf of Mexico. The rift is working its way to a nuclear power plant in Texas (can we get a bad science movie without nuclear energy destroying something in some form?). To stop it they blow up an oil field RIGHT NEXT TO THE PLANT! LOL! But the rift turns and heads to the Gulf of Mexico. When it reaches the gulf, water flows up the rift, creating a big river, hundreds of miles wide in the midwest U.S. For starters, this water would have to flow uphill!!! The midwest U.S. is at a much higher elevation than the Gulf of Mexico. As the movie ends, suddenly the rift extends all the way into Canada. How? Why? What? It just did.
A very confusing, very long, very boring, very bad science movie that has no clue how geological activity works. Avoid watching this, unless you're a Dean Cain fan, than go ahead and watch it. :-)
P.S. Oh yeah, a big part of the movie focuses on characters trapped in Las Vegas after the city is swallowed into the ground after a big sink hole developed. These characters play no role in the outcome of the story. They are simply there to waste your time. :-)