An Oil Well is an economic building used to gather Oil from oil patches. It becomes available in the Industrial Age, along with the resource oil itself, and requires both Timber and Metal to construct.
Once built, an Oil Well needs to be operated by a Citizen and gathers oil at a rate of 35 (per 30 seconds). When an Oil Well is destroyed or razed, the citizen operating it is automatically ejected from it. The citizen can also be ejected manually, leaving the structure without function (it still belongs to the nation, however, and blocks the oil patch from enemy access).
Oil Wells built at sea are called Oil Platforms. They have almost identical stats and operate in the same way, but have a slightly higher ramping cost. They also require a nation to own at least one Dock to allow citizens to embark on transport vessels in order to move to the construction site. Ramping cost for Oil Platforms and Oil Wells are linked together – constructing either structure increases the cost for the other as well.
The gather rate of oil can be increased globally by building Refineries, with each Refinery adding 33% to the base gather rate of oil.