二连盆地三种典型构造带岩性油藏形成模式分析

THE ANALYSIS OF FORMATION MODELS OF LITHOLOGICAL RESERVOIRS ON THREE KINDS OF TYPICAL STRUCTURAL ZONES IN THE ERLIAN BASIN

二连盆地各凹陷内部划分出3种典型构造带:陡坡带、缓坡带和洼槽带;不同的构造带岩性油藏成藏条件组合特征不同。通过解剖近几年隐蔽油藏勘探获得重大突破的凹陷中的典型岩性油藏,总结出适合二连盆地各凹陷中3个构造带的岩性油藏成藏条件组合模式。其模式分别为:陡坡带、缓坡带和洼槽带岩性油藏成藏条件组合模式。成藏条件组合模式不同,自然导致各构造带岩性圈闭成藏模式也不同,据此提出3种岩性油藏成藏模式:1)陡坡带自生自储型岩性油藏成藏模式,2)缓坡带旁生侧储型岩性油藏成藏模式,3)洼槽带下生上储型岩性油藏成藏模式。这3种成藏模式是目前二连盆地岩性油藏勘探突破的典型成藏模式。

The sags in Erlian Basin can be divided into three kinds of typical structural zones： steep slope, gentle slope and depression zone. These structural zones have different combination models of accumulation conditions. And the three models of accumulation conditions respectively are： the combination model of accumulation conditions on steep slope, the compounding model of accumulation conditions on gentle slope and the combination model of accumulation conditions on depression zone. In addition, different structural zones have different formation models of the lithological reservoirs. They can be summed up as follows： 1） the oil＇s generating and preserving in same formation on steep slope, 2） the oil＇s generating in a formation and preserving in sideward layer on gentle slope, 3）the oil＇s generating in lower formation and preserving in upper one on depression zone. The three typical models of oil accumulation are the breakthrough of the exploration of the lithological reservoirs in the Erlian Basin at present.