They decline significantly from one year to the next because each barrel of oil taken from a reservoir reduces the pressure within the field, leaving less force available to push the next barrel of oil up the well.

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The well is gushing because of the pressure the oil is under in its reservoir 4, 300 metres below the sea bed.

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And following the intersection of the well bore with those relief wells, they will put heavy mud down there to suppress the pressure of the oil coming up from the reservoir, put a cement plug in and effectively do what I would call a bottom kill, as opposed to the top kill, which was not successful a couple of weeks ago.

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