油气藏动力学成因模式与分类

DYNAMICS,MODELS AND CLASSIFICATION OF HYDROCARBON ACCUMULATIONS

根据油气运聚的动力和作用方式将油气藏成因分为 3类 8种 17式。这 8种分别是 :①高压势场作用下形成的油气藏 ;②低压势场作用下形成的油气藏 ;③油水携带溶解气游离释放形成的天然气藏 ;④浮力作用下形成的油气藏 ;⑤毛细管力作用下形成的油气藏 ;⑥天然气体积膨胀形成的深盆气藏 ;⑦分子吸附作用形成的煤层瓦斯气藏 ;⑧分子水合作用形成的水合甲烷气藏。①～③种为突发式流压作用形成的油气藏 ,④～⑥种为缓慢式烃势差形成的油气藏 ,⑦和⑧为非常规条件下天然气汇聚形成的特殊类型的 (油 )气藏。相同动力学成因的油气藏因实际地质条件的差异可以进一步分成亚类。不同动力学成因的油气藏的分布规律、主控因素和产状特征不同。研究油气运聚的动力机制和成因模式对指导油气田勘探、提高勘探效益具有重要意义。

On the basis of their habitats and driving mechanism, HC accumulations can be divided into 3 groups, 8 sub groups and 17 models. The 8 sub groups include: ① oil gas accumulations resulting from a high pressure potential field; ②oil gas accumulations under a low pressure potential field; ③natural gas reservoirs caused by release of dissolved gas from oil and water; ④oil gas accumulations originated from buoyancy; ⑤oil gas accumulations due to capillary pressure; ⑥deep basin gas accumulations; ⑦coal seam methane gas accumulations formed by molecular adsorption; and ⑧hydrated methane gas accumulations by means of molecular hydration. The above 8 sub groups can be classified into 3 groups: (1) oil gas accumulations by a paroxysmal fluid pressure, which include sub groups of ①～③; (2) oil gas accumulations by a steady and continuous hydrocarbon potential difference, including sub groups of ④～⑥; (3) gas accumulations formed under unconventional conditions, which may be represented by sub groups of ⑦～⑧. The oil gas accumulations with the same dynamic origin can be further divided into sub groups according to their actual geological conditions. The oil gas accumulations with different dynamic origins are of varying distribution patterns, major controlling factors and occurrence features. In order to guide oil gas field exploration and increase exploration benefit, it is important and necessary to study the dynamic mechanism and origin models for oil gas migration and accumulation.