Stacey Vanek Smith: Ohio has temporarily banned hydraulic fracking in some parts of the state, after a series of rare earthquakes including one that rocked Youngstown over the weekend. Eve Troeh joins us live from the Marketplace sustainability desk. Good morning, Eve.

Eve Troeh:Good morning.

Smith: So Eve, earthquakes in Ohio -- that seems surprising. What happened?

Troeh: It is surprising. There was a 4.0 quake -- that's unusually big for Ohio. But state officials say 11 quakes have happened in the past year, all linked to this one natural gas well close to Youngstown. So they're pretty sure it's fracking that's the problem. That's when natural gas drilling companies inject high pressure fluid down into layers of rock to get natural gas out. The industry says there's no proof that causes earthquakes.

Still, the state has banned fracking -- first at this one problematic well, and now at five miles around the well. That means five wells total are closed for the foreseeable future.

Smith: Ohio is not alone in trying to restrict fracking. How have other places dealt with the risk?

Troeh: Fracking is going on all over the country, and there are many, many efforts to restrict it. Ohio follows Arkansas, Oklahoma and Texas on regulating fracking near earthquake sites. In Pennsylvania -- that's the state that's maybe made the most money on fracking -- there've been efforts at a state ban, but those haven't gone far. Yet in the state's major industrial city of Pittsburgh, the city council unanimously voted to ban it.

Now on the flipside in Colorado, the state Supreme Court just ruled that cities cannot ban fracking. But local towns there are pushing back. They're making drilling companies pay for tests of local water supplies. So in 2012, we're going to see a lot more battles over fracking. They're only going to get bigger -- in Washington and in city halls all around the U.S.

Smith: Our own Eve Troeh. Thank you Eve.

Troeh:Thank you.