The oil and gas industry is used to handling the controlled release of oil and gas.
Uncontrolled release is called a blowout.
It happens.
The mining ships found hydrates on the surface or right below the surface, when it’s disturbed it can release all at once like a well blowing out only on a much larger scale, several acres in size so they said.
so they said
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Key part of your story. I’m confident you did the work and were told that information, I am not doubting you at all.
It probably happens with significantly changing conditions of sufficient magnitude, say a earthquake in the area.