China has started drilling a 10,000-metre (32,808 feet) hole into the crust of the Earth for what is set to be the deepest borehole ever made in the country.
The drilling started in the oil-rich Tarim Basin, in northwest China's Xinjiang region at 11:46 am on Tuesday, reported the official Xinhua News Agency.
The Tarim Basin, where the borehole is being constructed, is one of the toughest areas to explore because of its harsh ground environment along with complicated underground conditions.
The narrow shaft which is being constructed inside the ground, along with the drill bits and drill pipes which weigh more than 2,000 tonnes, will penetrate more than 10 continental strata, or layers of rock, according to the report, and reach the cretaceous system in the Earth's crust, which features rock dating back some 145 million years.
The construction of the borehole is a landmark event in the deep-Earth exploration of China, providing the nation with an unprecedented opportunity to study areas of Earth which are deep beneath the surface.
The borehole is being constructed in the hinterland of the Taklimakan Desert, which is China's largest desert.
The construction difficulty of the drilling project can be compared to a big truck driving on two thin steel cables," Sun Jinsheng, a scientist at the Chinese Academy of Engineering, told Xinhua.
President Xi Jinping called for greater progress in deep Earth exploration in a speech addressing some of the nation's leading scientists in 2021.
Earlier on Tuesday morning, for the first time, China sent its first civilian astronaut into space from the Gobi Desert.
The deepest man-made hole on Earth is still the Russian Kola Superdeep Borehole, which reached a depth of 12,262 meters (40,230 feet) in 1989, after 20 years of drilling.