Modulous
Experts on the subject of marine noises are fairly unanimous in agreement: It bears all the signs of being a marine animal that makes it. The problem - it was detected by sensors about 4,800km apart.
There is just one problem with the scenario given here as support for a marine mammal of some kind. As near as I can tell there has only been
one sond recording of the "bloop". What is strikingly absent from the picture is multiple recordings of this phenomena that would be more convincing evidence for the hypothesis.
It would be a real bonus if we could get more info on where these microphones were located and the relative strength of the recordings at each. Also I would note that there are many underwater microphones throughout the world and how many of them picked up the signal as well?