盆地模拟技术在洪泽凹陷的应用

APPLICATION OF BASIN MODELING TO THE STUDY OF HONGZE SAG IN NORTHERN JIANGSU BASIN

洪泽凹陷位于苏北盆地西北部,有一定勘探前景。通过盆地模拟研究认为洪泽凹陷的石油地质条件有其自身特点:a)生油岩成熟度低,现今成熟区仅限于深凹带附近;b)正常生烃模型计算的大量生排烃期较晚,在盐二段沉积末期以后,低未成熟油的大量生排烃期较早,一般在吴堡运动,三垛运动前;c)油源主要来自于低未熟油,且生排烃区集中于次凹的深凹带;d)油气运移距离短。洪泽凹陷油气生成、运移有资源少、生成早、成熟低、运聚短的特点。在洪泽凹陷找油气更需精雕细刻。

The Hongze sag is located in the northwest of the northern Jiangsu Basin, with some potential for hydrocarbon exploration. Based on the results of basin modeling, it can be concluded as following: a) most of source rocks are low matured and the matured source rocks are only restricted in the deep part of the sag; b) large scale of hydrocarbon generation and accumulation is occurred after sedimentation of Yancheng formation, but a lot of low or nonmatured oil were generated before Wubao and Sanduo movements; c) the deep part of the sag is the main area for hydrocarbon generation and accumulation; and d) distance of oil migration is short. In a word, the Hongze sag is characterized by low matured source rocks, short migration, and limited accumulation. It is necessary to pay more attention to the study of the sag for the sake of success of petroleum exploration in the area.