>> larue: just a well in the ground. >> whitaker: larue's disposal well is one of more than 3,000 ineated a website to explain the earthquakes. this map shows disposal wells as blue dots. the orange dots are earthquakes. when the price of oil went over $100 a barrel in 2008, oil and gas production increased dramatically. so did the amount of wastewater and earthquakes. what's causing these earthquakes? learned in oklahoma is that the earthquakes that are occurring in enormoumb result of waste water injection. >> whitaker: mark zoback is professor of geophysics at stanford university. zoback says there are two factors behind the earthquakes. one is the large volumes of water being disposed, and the other is where it all goes: deep down into a layer of earth called the arbuckle. what makes this such a good place to dispose of all that water? >> zoback: well, it's very thick. it's porous, it's permeable so it can accommodate, you know, very large injection rates. >> whitaker: the only problem with the arbuckle is that it sits directly on top of the crystalline basement, a rock layer rid

larue's oil wells produce more oil than petroleum. gas and oil collected in tanks for sea.ut the water is too briny to be recycled or used. it is considered waste. >> awful this is salt water. >> salt water. >> go back in the ground. have to get rid of it. >> reporter: getting rid of the water means sending it down a disposal well that's drilled deep below the freshwater, to prevent contamination and the zone where it came from. >> this is it? >> this is it. >> what all the talk is about. >> well in the ground. >> the disposal well its more than one of 3,000 in oklahoma. the state created a website to explain the earthquakes. this map shows disposal wells as blue dots. orange dots are earthquakes. when the price of oil went over $100 a barrel in 2008. oil and gas production increased dramatically. so did all. waste water. and earthquakes. >> what's causing these earthquakes? >> what we have learned in oklahoma is that the earthquakes that are occurring in, in enormous numbers are the result of waste water injection. >> the professor of geofikzs at stanford university. zobak

. >> reporter: librarian james larue helped compile the list.ransgender books, there are two about islam, two about mental disability, the bible which he says has appeared many times before, and "50 shades of gray." it was initially self-published erotica but went on to sell 1 5 million copies. it was later adapted to a movie. >> beyond this door. >> what is? >> my play room. >> reporter: what is the broad theme amongst the books that you have people saying these shouldn't number libraries? >> it's the outsider. it's wha society that mainstream america still feels some discomfort with. >> reporter: are you at the place where you can predict what people will be afraid of and when books might end up on the list? >> we certainly are close observers of our culture. if i look over the past year, we've had a surge of religious liberty bills, may transgender people use the restroom, or an attempt to, say, adopt the bible as the state book of tennessee, so often actions like this when any one group steps forward and says it needs to be like this, there'