I’ve read a couple articles quoting a professor at a Louisiana university that the reddish color of the oil slick is explained from release of materials compressed over millions of years that are uniquely mixing with the oil now. However, what about the prophecy of the waters being red like blood that kills everything in them? Is this prophecy suppose to happen before the 70th week begins?
Rev. 8:8 takes place during Daniel’s 70th week which hasn’t begun yet. When John didn’t know how to describe something he said it was like something he could describe. For example, he said the locusts looked like horses prepared for battle (Rev. 9:7). That doesn’t mean they are horses, only that they looked like battle horses. Sometimes he would say something resembled something else, like the heads of the horses resembled the heads of lions in Rev. 9:17.
But in Rev. 8:8 John didn’t say the water was “red like blood” or that it resembled blood. He said the water turned to blood. That means we should take it literally. This and the timing is why the oil spill is not a fulfillment of Rev.8:8, nor will it ever be. When Rev. 8:8 is fulfilled, one third of the water in the seas of the world will turn to blood.