This is why I have been investing in North American oil and gas producers.
Fear of attack or disclosure of error. Current oil prices (over $40) are the result of a fear of terrorism and increased demand. A similar price could be expected if data or technological risk are proven to be real. A sustained price of $40 will reduce global growth by 1% (-$500 billion in the first year).
Moderate attack. If global guerrillas attack Ghawar successfully, the price of oil will likely spike to $75 a barrel. This would slow global economic growth by 2.5% (a -$1.25 trillion loss).
Large attack. A successful attack on Ghawar and Basra would result in a price of $160 a barrel. Global economic growth would slow by 4.55% (a -$2.25 trillon loss) — essentially a global depression.