Shattered Sword went into detail at just how bad those carriers burned. They were literally glowing from the heat and they burned for quite some time. Ens. George Gay, who was floating in the water, relatively close, said he heard a VERY loud explosion from the Kaga. I bet the one that tore her apart.
I REEEEALLY wish SOMEONE would resume the search and documentation of those ships. I would LOVE LOVE to have the same video and hardback book that Robert Ballard did on the Yorktown 25 years ago. If you get a chance, look up that video. He took two guys from the Yorktown and even a Japanese "Kate" Pilot to the location. AWESOME stuff!