Green Field vs. Brown Field & Brown Reservoir vs. Green Reservoir in Iran’s Regulation.

Definitions from the Cabinet of Ministers Resolution on Upstream Petroleum Contracts Framework:

🔹Reservoir: Each of the anticlines, stratigraphic structures, or any type of structural trap containing hydrocarbons—or a combination thereof—with independent rock, fluid, and pressure characteristics.

🔹Discovered Field (Green Field): An oil or gas field discovered by the National Iranian Oil Company (NIOC) or by other companies on behalf of NIOC, which is ready to enter the development phase.

🔹Producing Field (Brown Field): A field that has previously been developed and has entered the production phase.

🔹Producing Reservoir (Brown Reservoir): A reservoir that has a history of commercial hydrocarbon production.

🔹Discovered and Undeveloped Reservoir (Green Reservoir): A discovered reservoir in which no commercial hydrocarbon production has yet taken place.