The Changqing shale oil field in Northwestern China has produced a cumulative 20 million tons of crude, Chinese media reported, noting the amount marks the start of a new phase in domestic oil production. The amount, equal to some 146.6 million barrels, is notable mostly because of the challenging geology of China’s shale deposits, which has made it more difficult to tap the oil and gas resources in them. However, on Beijing’s orders, the industry has delivered, boosting domestic production of both oil and gas considerably, notably…