Iraq Oil Infrastructure (source)
From Lieutenant General Martin Dempsey's testimony (watch it on CSPAN) at the House Armed Services Subcommittee hearing on Tuesday, June 12:
Nearly 90% of Iraq's total revenue depends on two offshore oil terminals in the Persian Gulf. The Al-Basra Oil Terminal (ABOT) pumps oil worth 83% of that revenue, while Khor al-Amaya's output (KAAOT) makes up 5-6%. They are protected by a "ring of steel" about which you can read more in one of Michael Yon's older dispatches.