Revelation 16:3
And the second poured out his bowl upon the sea; and it became as it were the blood of a dead man: and every soul of life died, whatsoever were in the sea.
Revelation 8:8-9
And the second angel sounded, and as it were a great mountain burning with fire was cast into the sea: and the third part of the sea became blood;
Revelation 11:6
They have power to shut up the heaven, that the rain may not fall during the days of their prophecy: and they have power over the waters to turn them into blood, and to smite the earth with every plague, so often as they may wish.
Revelation 10:2
and having in his hand a little open book. And he placed his right foot upon the sea, and his left upon the earth,
Revelation 13:1
And I stood upon the sand of the sea. And I saw a beast rising up out of the sea, having ten horns and seven heads; and upon his horns ten diadems, and upon his heads names of blasphemy.