China begins drilling one of world's deepest holes in hunt for discoveries deep inside the Earth

China has begun digging its deepest borehole in an effort to study areas of the planet deep beneath the surface. The drilling of the borehole began on Tuesday in a desert in the Tarim basin in China's north-western region of Xinjiang, according to the Chinese state-run Xinhua news agency. With a planned depth of 11,100 metres, the narrow shaft will penetrate more than 10 continental strata and reach the cretaceous system in the Earth's crust - a series of stratified rocks dating back 145m years. The project is expected to be completed in 457 days and has been hailed by…