Re­searchers con­vinced of tie be­tween earth­quakes, oil and gas drilling

The China Post - - LIFE - BY ALI­CIA CHANG

Sci­en­tists are now more cer­tain than ever that oil and gas drilling is caus­ing hun­dreds upon hun­dreds of earth­quakes across the U.S., with the ev­i­dence com­ing in from one study af­ter an­other.

So far, the quakes have been mostly small and have done lit­tle dam­age be­yond crack­ing plas­ter, top­pling bricks and rat­tling nerves. But seis­mol­o­gists warn that the shak­ing can dramatically in­crease the chances of big­ger, more danger­ous quakes.

Up to now, the oil and gas in­dus­try has gen­er­ally ar­gued that any such link re­quires fur­ther study. But the rapidly mount­ing ev­i­dence could bring heav­ier reg­u­la­tion down on drillers and make it more dif­fi­cult for them to get projects ap­proved.

The po­ten­tial for man- made quakes “is an im­por­tant and le­git­i­mate con­cern that must be taken very se­ri­ously by reg­u­la­tors and in­dus­try,” said Ja­son Bord­off, found­ing direc­tor of the Cen­ter on Global En­ergy Pol­icy at Columbia Uni­ver­sity.

He said com­pa­nies and states can re­duce the risk by tak­ing such steps as mon­i­tor­ing op­er­a­tions more closely, im­pos­ing tighter stan­dards and re­cy­cling waste­water from drilling in­stead of in­ject­ing it un­der­ground.

A se­ries of gov­ern­ment and aca­demic stud­ies over the past few years — in­clud­ing at least two re­ports re­leased this week alone — has added to the body of ev­i­dence im­pli­cat­ing the U.S. drilling boom that has cre­ated a bounty of jobs and tax rev­enue over the past decade or so.

On Thurs­day, the U.S. Ge­o­log­i­cal Sur­vey re­leased the first com­pre­hen­sive maps pin­point­ing more than a dozen ar­eas in the cen­tral and eastern U.S. that have been jolted by quakes that the re­searchers said were trig­gered by drilling. The re­port said man-made quakes tied to in­dus­try op­er­a­tions have been on the rise.

Sci­en­tists have mainly at­trib­uted the spike to the in­jec­tion of waste­water deep un­der­ground, a prac­tice they say can ac­ti­vate dor­mant faults. Only a few cases of shak­ing have been blamed on frack­ing, in which large vol­umes of wa­ter, sand and chem­i­cals are pumped into rock for­ma­tions to crack them open and free oil or gas.

“The pic­ture is very clear” that waste­water in­jec­tion can cause faults to move, said USGS geo­physi­cist Wil­liam Ellsworth.

Un­til re­cently, Ok­la­homa — one of the big­gest en­ergy-pro­duc­ing states - had been cau­tious about link­ing the spate of quakes to drilling. But the Ok­la­homa Ge­o­log­i­cal Sur­vey ac­knowl­edged ear­lier this week that it is “very likely” that re­cent seis­mic ac­tiv­ity was caused by the in­jec­tion of waste­water into dis­posal wells.

Earth­quake ac­tiv­ity in Ok­la­homa in 2013 was 70 times greater than it was be­fore 2008, state ge­ol­o­gists re­ported. Ok­la­homa his­tor­i­cally recorded an av­er­age of 1.5 quakes of mag­ni­tude 3 or greater each year. It is now see­ing an av­er­age of 2.5 such quakes each day, ac­cord­ing to ge­ol­o­gists.

Yet an­other study, this one pub- lished Tues­day in the jour­nal Na­ture Com­mu­ni­ca­tions, con­nected a swarm of small quakes west of Fort Worth, Texas, to nearby nat­u­ral gas wells and waste­water dis­posal.

The Amer­i­can Petroleum In­sti­tute said the in­dus­try is work­ing with sci­en­tists and reg­u­la­tors “to bet­ter un­der­stand the is­sue and work to­ward col­lab­o­ra­tive so­lu­tions.”

The En­vi­ron­men­tal Pro­tec­tion Agency said there no plans for new reg­u­la­tions as a re­sult of the USGS study.

For decades, earth­quakes were an af­ter­thought in the cen­tral and eastern U.S., which wor­ried more about tor­na­does, floods and hur­ri­canes. Since 2009, quakes have sharply in­creased, and in some sur­pris­ing places.

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