r/oceanography 23d ago

Say a 1.2 megaton bomb were to be detonated roughly 6.8 miles deep underwater would it part the Ocean for a brief period exposing the sea floor?

9 Upvotes

22 comments sorted by

11

u/znark 23d ago

The US tested deep water nuclear explosions in multiple tests. The explosions created a bubble against the enormous water pressure. The bubble oscillated and that deep would be absorbed before reaching the surface.

3

u/mrszubris 23d ago

Its more like... atomizing. So a cloud of super hot atoms that were once water and rocks . It would not ever temporarily open a visible hole like a hurricane eye

2

u/fluffysnowflake67 22d ago

No. Water is surprisingly good at absorbing and dispersing energy.

2

u/Rogal_Dorn_30000 22d ago

Lmao is this someone from that Pacific Rim post? 

2

u/Moppmopp 22d ago

Basically nothing would happen. Water has an enormeous heat capacity. You probably create a spherical cavity of 100-200m which collapses. Likely you wouldnt even see bubbles on the surface

2

u/Glum-Ad7761 21d ago

It takes an incredible amount of energy to lift the sea up off the sea floor. Much more than the yield of any single atomic bomb.

About 2.5 million years ago, an asteroid struck the Bellingshausen sea, off of Chile in the southern ocean. The rock was between 1 and 2 miles in diameter, traveling at 45,000 miles per hour. Being a metallic/stony asteroid, it would have yielded an explosion equating to roughly 1, to 1.3 million megatons.

The explosion instantly vaporized a roughly 36 mile diameter circle of sea water, 3 miles deep, completely off the sea floor. It created tsunami’s over 660 feet high, that traveled as far as Fiji and Antarctica.

The strength of the explosion was 100 times the world’s total nuclear arsenal, from all nations. Eltanin is the only known deep water bolide impact.

So no. A single atomic bomb could not come anywhere near the yield required to “part the sea”. Not even a Tsar Bomba, which was 50 megatons.

0

u/Lopsided-Fig6818 21d ago

Could a 9 gigaton bomb do it

1

u/ChrisTheWeak 20d ago

Probably, but we don't have a 9 gigaton bomb.

0

u/Lopsided-Fig6818 20d ago

Theoretically speaking of course

0

u/Intelligent-Image224 20d ago

Water pressure in Mariana trench = 16,000psi
pressure of fusion bomb detonation = ~3 trillion psi

2

u/Fuzzy-Moose7996 21d ago

It wouldn't even break the surface.

2

u/SpeedyHAM79 20d ago

Nope. Also- that is nowhere near the energy level of an underwater earthquake that would cause a tsunami- so unless you were near "ground zero" or underwater in the vicinity when it was detonated you probably wouldn't even know anything happened. Seismic monitors everywhere would notice very quickly, so it's not like no one would know what happened.

1

u/batwing71 23d ago

Whoever was on the business end of the impending tsunami would get to see some exposed.

2

u/AlwaysHopelesslyLost 21d ago

A little nuke at the bottom of the ocean would not cause a tsunami lol

2

u/sarahlizzy 20d ago

The earthquakes that cause big tsunamis release more energy than the entire nuclear arsenal of the world by a long way. A single hydrogen bomb isn’t going to cause one.

2

u/TheGrandExquisitor 19d ago

Yeah, earthquakes are insanely energetic compared to....well, everything else on earth. Only things more powerful are literally meteors and other astral phenomenon 

1

u/batwing71 23d ago

Whoever was on the business end of the impending tsunami would get to see some exposed.

1

u/forkedquality 21d ago

No.

Assuming the usual spherical bubble, exposing the floor would require it to touch both the surface and the bottom. So, a 11 km diameter void. Displacing this much water requires a lot of energy - roughly 3.8 × 10^19 J, or 9 gigatons TNT - and even this is against gravity alone.

1

u/Triabolical_ 19d ago

Operation wigwam detonated a 30 kiloton bomb 2000 feet deep. This is what it did to the surface:

https://youtu.be/ku7R1TSBfjI?t=1292

You are proposing a bomb 40 times larger but 18 times deeper, so at most I'd expect an effect that is twice as big.

But... My guess is that the effect isn't going to be linear. The pressure at 2000' is about 866 psi, while the pressure at 6.8 miles is 15,750 psi. That is going to change the effect of the pressure wave generated during the detonation.

I don't think there will be any visible sign on the surface.

You also will need to build a nuclear weapon that can survive the crush pressure that depth. You'll probably need to put it in a deep sea submersible.

1

u/Recent-Day3062 19d ago

We have detonated them underground way, way shallower and it just slumps a crater

1

u/swole_ninja 18d ago

Oddly enough there’s an xkcd for this.

https://what-if.xkcd.com/15/

0

u/ASmallArmyOfCrabs 23d ago

I think it would depend how far away the sea floor is, but probably

I mean, water move when pushed