2. The sum of oil and gas reservoirs in the same oil and gas producing area controlled by a single geological structure (or stratum). Oil and gas fields may have one or more oil and gas reservoirs. In the same area, oil fields are dominated by oil reservoirs, and gas fields are dominated by gas reservoirs. According to the geological factors in the oil and gas production control area, oil and gas fields are divided into three categories: ① structural oil and gas fields. Refers to the oil and gas production areas controlled by a single structural factor, such as folds and faults. (2) Stratigraphic oil and gas fields, the oil-bearing area controlled by stratigraphic factors (such as stratigraphic unconformity, pinch-out and lithologic changes, etc.). ) is a regional anticline or monoclinic structure with background. ③ Composite oil and gas field. An oil and gas field that is not controlled by a single structural or stratigraphic factor, but by a variety of geological factors.