The sandy stretches of the Taklamakan Desert in Xinjiang hold a treasure: oil. On the Tarim oil field, China National Petroleum Corporation has started to drill boreholes that will reach a depth of 10,000 meters within 457 days, penetrating more than ten continental layers. This will reach the Cretaceous formation in the Earth’s crust – and with it, rock that is about 145 million years old. The project will provide data on the Earth’s internal structure and test technologies for deep drilling. The world’s deepest borehole has been located in Russia since 1989, at a depth of 12,262 meters – work on it took 20 years.