[Jolly Amaranto]

I would think that all the air would be collapsed into almost no volume at all at the pressure down there. Maybe even dissolved into the water. I have done a lot of resin casting in RTV silicone molds. I degas the silicone first in a vacuum but even after that, there are still a few bubbles left if not cured under pressure. If I run the pressure up to 80 psi in a modified paint pot and let the RTV cure, any air bubble just vanish. After the RTV has cured the bubbles do not come back. I guess they just diffuse into the RTV. The same with the resin. A properly vented RTV mold will still produce resin parts with bubbles unless cured at 80 psi. The pressure at the Titanic depth is way more than my little paint pot.