>>11939269The Sedan Crater is a mere 300 feet deep. Continental crust is 20+ miles, so if you were somehow able to make a perfect cylindrical hole with none of the material falling back down, it would still be over 300 explosions deep. Realistically you would need to perform some sort of cone-shaped excavation which would need tens of thousands of explosions. It might be more feasible using much better nukes (full scale tsar bomba is 1000 times larger than Sedan) on a closer magma source, such Yellowstone, but that's a caldera, not specifically the mantle. Underwater excavation would be even more problematic because the water would prevent the ejection of material.
