If you don't like HFTs, this is an idea you'd probably like to give them. Nobody has ever drilled through the Mohorovicic. It is unclear whether or not it is possible to do so.
The most-likely outcome is a few happy geologists/geophysicists and a number of very-sad HFT underwriters.
It says it's 10 to 20 km below the ocean floor. Are we as humans been digging in the ocean floor that deep, or even at all? That sounds like sci-fi to me, I'd love to learn more if that's actually feasible.
We have two. I suspect that you are thinking of Yellowstone, but there is also the Long Valley Caldera in Eastern California. The Mammoth Mountain area.
