渤海湾盆地变换构造特征及其成藏意义

Transfer structure and its relation to hydrocarbon exploration in Bohai Bay Basin

依据前人对变换构造的分类研究,分析了渤海湾盆地变换构造的特征。将渤海湾盆地变换构造分为变换带和变换断层两种类型:一般表现为变换带样式,尤其是在盆地或坳陷层次;而变换断层仅在局部的控凹层次上有所体现。高级别的变换带大多数是由一系列不同类型的传递斜坡横向串联而成,间或发育变换断层。北西西—北西向的变换构造是渤海湾盆地"南北分块"构造格局的主控构造样式,而渤海湾盆地油气储量的差异与变换构造控制的富生烃凹陷及洼陷分布有关。变换构造控制的古地形和富砂水系通道有利于形成岩性油气藏,变换构造邻区的高部位则是发现(潜山)构造油气藏的重要地区。

On the basis of the previous classification research, the features of transfer structure in Bohai Bay Basin were analyzed. The transfer structures in Bohai Bay Basin can be divided into two styles of transfer zone and transfer fault according to the connec tion or non connection status. The transfer structure in Bohai Bay Basin is mainly exhibited in the style of transfer zone, especially in basin or depression, while the transfer fault only militates in the sag-control level. With the occasional development of transfer fault, most of high level transfer zones are horizontally connected with different relay ramps. These strike transfer structures in NWW-NW direction are the most important structure styles to control the ＂north-south segmentation＂ tectonic framework in Bohai Bay Basin. The difference of oil and gas reserves in Bohai Bay Basin is related to the distribution of prolific hydrocarbon depressions and sags controlled by transfer structure. The paleotopography and rich-sand drainage channels controlled by transfer structure are favorable to the formation of lithologic reservoirs. The adjacent zones of the transfer structure are the important regions for finding the buried- hill structure reservoirs.