Pic: AP.

BEIJING (AP) — A research group says more than 60 percent of China’s vast shale gas deposits are in regions with scarce water resources, complicating plans by the energy-hungry country to tap the natural gas.

The World Resources Institute says China has the world’s largest reserves of natural gas trapped in deep shale rock. Commonly known as fracking, shale gas mining requires pumping large quantities of water mixed with chemicals into deep wells to break apart shale rock.

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The U.S.-based institute said in a report issued Tuesday that 38 percent of the world’s shale gas is in areas with scarce water.

China, Argentina and Algeria have the world’s biggest shale gas deposits.