Oil (Civ4)

Revealed by	Scientific Method
Resource value	+1
Improvement	Well or Offshore Platform, available with Combustion or Plastic
Well value	+2 , +1
Allows/Enables	Battleship, Bomber, Carrier, Destroyer, Fighter, Gunship, Jet Fighter, Panzer, Mechanized Infantry, Missile Cruiser, Mobile Artillery, Mobile SAM, Modern Armor, Submarine, Stealth Destroyer, Tank, Transport

Oil appears in game as a black puddle shooting out black circles. It can appear in any terrain, including water.

Civilizations with cities where the Standard Ethanol corporation is present automatically receives one of this resource.