Am I the only one hoping that what the admirals did to stop the quake wasn't Haki? I mean I can understand what Marigold and Sentomaru did creating some sort of repulsive force on their own hand/body. However to cover a whole building man that is just too freaking magical. You could even see some sort of shield or something like out of Star Trek. Maybe its some sort of Vegapunk invention powered by logia abilites.
Its actually pretty obvious that it was Haki,
First, their hands are in the same positions Sentomaru's were
Second, the fact that the area was large doesn't mean anything Raleigh knocked out every person in a building so he could alone cover a building proving it should be easy for 3 people of immense power to stop an attack, even if very powerful, on a building.
Third, they aren't using a machine or we would see it in the picture.
Fourth, That magical stance is so ******* awesome it must be Haki.