A Japanese company engaged in oil and natural gas exploration and production said it found crude oil from a gas field in Akita prefecture, in a step towards potential shale oil production at home, Wall Street Journal reports.

Japan Petroleum Exploration Co. or Japex announced Wednesday that it had successfully extracted crude oil from a test sample from the Ayukawa oil and gas field. Japex extracted the crude oil from the bedrock by pumping hydrochloric acid at about 1,800 meters deep beginning Monday.

The company estimates that there could be some 5 million barrels of shale oil deposits around the gas fields alone, with “twenty times that amount” in the sedimentary rock in all of Akita prefecture. The estimated shale oil deposits could be worth nearly 10% of Japan’s annual oil consumption, according to The Japan Times. Japex said it would construct a new well at the oil and gas field in fiscal 2013 to study feasibility of commercial shale oil production.

The discovery comes at a time when Japan is attempting to “diversify its energy sources and develop untapped resources”.