Conventional (1)
US conventional earth penetrating weapons (EPW) the GBU-28 and GBU-37 can break through 6m of reinforced concrete or 30m of earth
Guided by laser or GPS they may also carry a 'smart fuse' which detonates the weapon at a pre-programmed point
Insufficient penetration for use against "hardened and deeply buried targets"
Nuclear (2)
A nuclear EPW such as the B61-11 can only penetrate 2-3m but even a shallow underground nuclear explosion produces an intense and damaging seismic shock
Depending on the rock type, this could potentially crush a bunker at about 70 metres depth
But the missiles cannot penetrate deeply enough for the radioactive fallout to be contained
