Try to picture this. All the water next to a ship mysteriously flowing away from the ship, over the bubble while the ship for some reason is the only thing going down through it.
Water is also heavier than air, and water on top of a bubble will also fall into the center of the bubble (breaking it up into smaller bubbles), until the surface tension of the water around the bubble is great enough to hold it together (small bubble).
Therefore a huge bubble gets split into many bubbles, I suppose at depth a lot of the gas gets dissolved into the water. The worst that would happen is many small bubbles cause the density of the water to decrease, causing the boat to sink lower into the water. I'm not sure if the water could lose enough density to sink a regular boat directly?
I think what you may be thinking of is large, shallow explosions (generally man made) under a ship which create a temporary bubble which then collapses in on itself, but can cause extreme stress on large ships.
Water is also heavier than air, and water on top of a bubble will also fall into the center of the bubble (breaking it up into smaller bubbles), until the surface tension of the water around the bubble is great enough to hold it together (small bubble).
Therefore a huge bubble gets split into many bubbles, I suppose at depth a lot of the gas gets dissolved into the water. The worst that would happen is many small bubbles cause the density of the water to decrease, causing the boat to sink lower into the water. I'm not sure if the water could lose enough density to sink a regular boat directly?
I think what you may be thinking of is large, shallow explosions (generally man made) under a ship which create a temporary bubble which then collapses in on itself, but can cause extreme stress on large ships.
Extremely contrived example of bubbles being able to sink a small boat: https://www.youtube.com/watch?v=MSmAXp_BHcQ
How a bubble generated by an explosion can actually sink a large ship: https://youtu.be/UdFNuc5XtII?t=192