Where will all the oil from Deepwater Horizon go? © Getty Images

Where will all the oil from Deepwater Horizon go?

The effects of the Deepwater Horizon oil spill is likely to be seen for decades.

Asked by: Anonymous

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The Mississippi Canyon 252 oil well sits at the bottom of the Gulf of Mexico, 1522m below the surface of the ocean. The oil is gushing out of the damaged wellhead at an estimated rate of 2100 litres a minute. That’s more than an Olympic swimming pool every day. Crude oil is a varied mixture of different hydrocarbons with different viscosities and densities. The lighter fraction will float on the top of the water, where the most volatile compounds simply evaporate. This can account for 30 per cent of the total volume. Over the course of a few days or weeks, wave and wind action whip what remains into a kind of mousse. This is being dragged by the main Gulf Loop current up along the east coast of the US towards the Arctic. But much of the spilling oil seems to be lurking in a plume around 1000m below the surface. Ocean currents are much weaker there, so the oil tends to collect and without the turbulence at the surface, it doesn’t get broken up, so bacterial digestion happens much more slowly. Some will clump together as golf balls of tar and sink to the seabed. The rest will eventually wash up on the shores of the Gulf of Mexico. Possibly for decades.


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