What's the difference between blood and the blood of a dead man?

Revelation 8:8 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 16:3 And the second angel poured out his vial upon the sea; and it became as the blood of a dead man: and every living soul died in the sea.

Is the blood in 8:8 red and fresh, but in 16:3 is it dark and rancid?