Probably, it's problematically to surprise our regular readers. All at once guessed that these are bacteria, but let's discuss how they did it. To begin with, remember what a friction force is? Friction force is responsible for the fact that the sofa standing on a smooth surface is much easier to move than on a carpet, and that a large amount of iron ore is a practically immobile monolith. And now imagine that suddenly the constant of friction has decreased and your sofa or our mineral have appeared on a very slippery surface. In this case, a small push will suffice to move them from the surface. So, let's put it all together: dry cargo ship, laden with ore, a storm and a big motions, sharply reduced coefficient of friction, a multiton load hits the walls of the ship, the center of gravity changed, it broke and went down. Did I forget anything?
Ah, yes ... who reduced the force of friction? Warm, humid conditions, a large number of nutrients - these are the ideal conditions for the reproduction of bacteria. They formed on the surface of the ore film, a kind of lubricating oil, which is used in engineering. But unfortunately, not where necessary.