(Bloomberg View) — Not so many years ago, earthquake science wasno more relevant to Oklahoma than marine biology. But these daysthe state is shaking way more often than California, and givingmany people there an unwanted crash course in seismology.

Last year, Oklahoma had 585 earthquakes with a magnitude 3.0 orgreater (big enough for people to easily feel) — almost three timesas many as California had and up from an average of just two a yearbefore 2009. Not coincidentally, that's when oil and gas drillersbegan injecting wastewater from fracking operations into thousandsof underground wells. In the past week alone, Oklahomans have feltthe earth move eight times — which is probablyeight times more than nature intended them to. It'senough to get officials, even in a drilling-friendly state, to takeaction to manage wastewater wells.

The phenomenon isn't mysterious. Geologists have known for manydecades that when pressure underground is changed — when peopleinject water, for example, or extract geothermal energy – - latentearthquakes can be triggered. While the great majority offracking-wastewater wells have no such effect, some — especiallythose in which great volumes of water reach crystalline basementrock that lies close to a fault — induce earthquakes that otherwisemight not have happened for hundreds of years.

There's also a whole lot more shaking going on in Arkansas,Colorado, New Mexico, Ohio, Texas and Virginia, too. But the mosttremors have been reported in Oklahoma.

So far, the injuries to humans and damage to chimneys andfoundations from the uptick in seismic activity have been mostlyminor. But scientists aren't able to predict this seismicity, orwhether it is likely to continue to grow in frequency andstrength.

What's most scary is that no one knows exactly how big quakescould get in the mid-continent. In 2011, one Oklahoma quakeregistered magnitude 5.7. And 1,300 years ago, the geologicalrecord shows, an area that is now within the state withstood aquake of magnitude 7– far more powerful than anything anticipatedby local building codes.

For the moment, it's not even clear whether the problems arecaused by individual wells or a bunch of them applying pressure inconcert. Sometimes well injections can trigger earthquakes milesaway, and sometimes the effect is delayed by months or evenyears.

Yet there are ways to manage the threat, U.S. Geological Surveyscientists Arthur McGarr and William Ellsworth and severalcolleagues argue in an article in Science last week. Itwould be wise, for example, to keep wastewater wells away fromcities. And it's important to monitor seismicity more precisely. Byfinding out exactly where small quakes are happening, it may bepossible to map any larger faults that wastewater injection isnudging to life. At the same time, oil and gas drillers shouldreport publicly where they're drilling wells, how much waterthey're injecting and how deeply.

Then regulators can keep an eye on any trouble using a so-calledtraffic-light approach: If seismicity in a certain area reaches athreshold magnitude, injections are slowed. Colorado officialstried this successfully last year with a well that had triggeredunaccustomed shaking near Greeley. In some cases, a well may needto be shut down — as the Oklahoma Corporation Commission did with awell near Cherokee after a 4.1 magnitude quake earlier thismonth.

The oil and gas industry has every reason to want to track andmanage the problem: Injection wells aren't cheap, and no one wantsto drill one that can't be used.

To the extent that drillers can learn to clean and re-use theirfracking water (up to a million gallons for every wellhead) they'llbe able to ensure they maintain a reliable water supply — and stopshaking things up so much above ground.

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