implosion

I find the conjecture that the sinking stern of the Titanic 'imploded' soon after sinking rather difficult to comprehend, particularly in relation to the sinking stern. Why would the air pockets "burst inwards"? I am a retired scuba diver and have visited over 25 ship wrecks around the world...

Did the Titanic literally fall apart at the seams? The hull seams to have stripped off at the bottom quite significantly on the port side. ....and stripped away from the bottom on the starboard side as well. Here is a photo of the Olympic's bottom. Does anyone know what these are...