spwm chineseshalePetroChina, an arm of state-owned China National Petroleum Corporation (CNPC), added almost 741 billion cubic meters to its shale-gas reserves in the Sichuan province and certified reserves of 358 million tons at the Qingcheng oil field.

The company said it had made a breakthrough in shale-oil and gas exploration, which led to the upgrade in reserves. The total proven reserves in the two shale gas blocks in Sichuan are in excess of 1 trillion cubic meters of gas, PetroChina said.

Shale gas is seen as a potential solution to China’s energy problem of demand outstripping supply. However, copying the U.S. shale boom hasn’t been easy.

China has recoverable shale-gas reserves of 1,115 trillion cubic feet, according to a 2015 estimate by the U.S. Energy Information Administration (EIA). This gives China the largest reservoir of shale gas, with Argentina a distant second. Yet, it is unlikely that China will repeat the U.S. shale gas boom.

This is because China’s shale-gas deposits are in remote, geologically challenging areas. “Geologically challenging” translates to being in mountainous regions. Add to that the gas-bearing rocks are much deeper than they are in the U.S. shale patch. Even so, investment in unconventional oil and gas exploration has been on the rise in the last few years. Earlier this year, PetroChina said it had achieved a promising daily production rate from a shale-oil find in western China.