大庆探区外围中新生代盆地类型及确定依据

盆地类型是油气远景评价的关键参数之一,不同类型盆地的叠加关系反映了不同时期成盆动力体系的不同.大庆探区外围中新生代盆地是经历强烈构造改造残留的叠合盆地.大地构造位置、基底组成和结构的差异,导致不同成盆期的盆地类型不同.按照盆地的成因分类主要发育裂谷(断陷)、拉分、前陆(挤压)和拗陷4种盆地类型,及前陆\断陷、断陷\拗陷、陆缘裂谷\断陷\挤压\拉分3种叠加形式.提出了按照构造层约束的4个成盆期演化.通过对盆地演化、古地理环境、构造运动等资料分析,确定了4期盆地演化的盆地类型.

DETERMINATION OF THE TYPES OF THE MESO-CENOZOIC BASINS IN THE PERIPHERY OF DAQING EXPLORATION AREA

The type of the basin is one of the key parameters for oil and gas prospect evaluation. The superimposing relations of different types of basins reflect the dynamic systems of basins during different forming periods. The MesoCenozoic basins in the periphery of Daqing exploration area are the results of remaining superimposition by strong tectonic reformation. The variation of tectonic locations, basal compositions and structures leads to different types of basins in forming stage. Base on the origin, the basins can be classified into four types, i.e. rift (fault-depression) basin, pull-apart basin, foreland (compressive) basin and sag basin, with three superimposing relations-foreland-fault-depression, faultdepression-sag and continental margin rift-fault-depression-compression-pull apart. The evolution of the basins is in four stages controlled by structural levels. With analysis on the basin evolution, paleogeographic environment and tectonic movement, the basin types during the four evolution stages are determined.