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China’s Drilling Ambitions & The Quantum Internet

This Is Why China Wants To Drill Through The Earth’s Crust

Image: Guangzhou Marine Geological Survey

China wants to drill through Earth’s crust – something the Americans tried, unsuccessfully, 60 years ago. And the Chinese aren’t just doing it for fun. What do they hope to find there? Let’s have a look.

In the 1960s, the Americans had a bold plan: they wanted to be the first to drill through Earth’s crust and into the underlying mantle. The mantle is normally about 35 kilometres down on land, but under the ocean floor it can be just 5 to 10 kilometres deep. So they picked a spot off the coast of Mexico, where the crust is thinner. The project was called “Mohole.” It’s named after the Mohorovičić discontinuity, which is the boundary between the crust and the mantle.

They began drilling into the ocean floor. But in 1966, after reaching just 183 metres below the seabed, the project was cancelled – it was too difficult and too expensive and no one besides scientists was really interested.

Now the Chinese want to do it for real. And they’ve got experience. Just two years ago, they began drilling a 10-kilometre-deep borehole on land, in the Tarim Basin. Why? Likely oil. Because if you drill 10 kilometres down and find a McDonald’s you don’t get to keep the burgers.

But China imports about 70% of its oil, and the Tarim Basin is one of their most promising regions. What makes it unusual is not that it has oil, but how deep it is. This basin has continental crust buried deep under sediments. As a result, oil that would normally be found at 2 or 3 kilometres down has ended up more than 8,000 metres below the surface. So they had a good reason to drill.

The project began in 2023 and just finished in February. It reached a depth of 10,910 meters. That is still somewhat less than the deepest hole in the world, the Kola borehole in Russia which is a little more than 12 thousand meters deep. But the Chinese might well break this record with their next project.

For this, they’ve built a new ship called the Mengxiang, which means “dream.” It’s designed to remain stable in one location and then lower down a pipe in segments and a drill until they reach the sea floor. From there it can drill more than 10 kilometers deep, which should be enough to reach the mantle.