At
the beginning of The Wine Dark Sea, the Captain and his crew
experience a rain of volcanic bombs. This natural phenomenon occurs
from volcanoes that arise at subduction zones. As the movement of
the tectonic plates forces one plate under another, most often a sea floor
under a continental plate, volcanoes form. In an area where the ocean
floor, with its sediments and decayed organisms (rich in water and carbon)
are forced downwards, they become super-heated and volcanoes form to release
the pressure of the steam and other gases. The gases, mixed with
molten lava, make explosive eruptions and, sometimes, form volcanic bombs.
So many of the Doctor's observations
of natural phenomena were at sea, we should cover some of those.