Harmonically coupled directed energy weapons. Basically, everything in the universe has a wavelength or lambda. If you find that wavelength you can add energy into it. This is what is meant by amplification. If you add an equal amount of power 180 degrees out of phase from a things lamda, then you destroy that thing. If you alternate between amplification and destruction, then you can heat or excite that thing. If you were to identify a large body of material, for example iron deposit a few hundred miles underground and if you could generate a sufficiently powerful enough radio signal and carry it on a robust enough antenna then you could harmonically couple with that deposit and make it dance. The pressure it would generate against surrounding rocks would cause earthquakes, landslides, etc. The best defense against this type of weapon is your own harmonically coupling radio antenna to detect and juxtapose a counter signal to the one being generated by your opponent. Alternatively, you could destroy the cooling system of your opponents radio.

HAARP was the first generation proof of concept of this type to be practically fielded.