松辽盆地南部岩性-地层油气藏成藏规律

Study on Hydrocarbon Accumulation of Litho-Stratigraphic Traps in Southern Songliao Basin

随着松辽盆地南部大型构造圈闭勘探的不断深入,勘探的目标区已经逐渐转移至以岩性因素起主导作用的非构造油气藏。由于岩性-地层圈闭形成的地质条件和分布规律具有复杂性和隐蔽性两个显著特点,所以它的规律性难以认识,其勘探难度也很大。但通过新方法、新技术的应用和地质认识的不断深入,岩性-地层油气藏展现出了较大的勘探潜力,吉林油田近2—3年来的大发现和新增储量的80%是在有一定面积的三角洲前缘薄互层中获得的,在这个领域中仍有6×108t的石油资源有待勘探,特别是松辽盆地南部地层-岩性圈闭是未来油气勘探的重要领域,具有进一步解剖研究和勘探价值,因此,对松辽盆地岩性-地层油气藏成藏规律进行研究,对于松辽盆地南部勘探有着十分重要的意义。

With further exploration of major structural traps in southern Songliao basin, the prospecting target has gradually focused on the non-structural reservoirs dominated by litho-stratigraphic traps. However, the complex and hidden nature of this type of reservoirs in geologic condition and distribution pattern cause them to be difficuh to understand or recognize, adding the difficulty for their explorations. The great potentials for exploration of litho-stratigraphic reservoirs do not appear until new methods and technologies have been applied and in-depth understandings have been gained. In recent two or three years, big discoveries have been made in Jilin oilfield, in which 80 percent of reserves are found in some areas of thin sand-shale interbedding of its delta front. There still exist petroleum potentials amounting to 6×10^8t for exploration in this area, especially in southern Songliao basin where the litho-stratigraphic traps will be more important domains and deserve extra attention. Hence, geologically speaking, this study on the hydrocarbon accnmulation of litho- stratigraphic reservoirs in Songliao basin is of vital significance to exploration of the southern Songliao basin.