辽东湾坳陷挤压型和拉张型走滑转换带特征及其控藏作用

走滑转换带对油气成藏具有明显的控制作用,辽东湾坳陷发育的走滑转换带控制了该区大中型油气藏的形成。利用三维地震精细构造解释并结合钻探结果,将走滑转换带分为右旋左阶—挤压型走滑转换带和右旋右阶—拉张型走滑转换带,并明确了两种转换带对油气成藏的控制作用。研究认为:挤压走滑转换带可形成规模较大的背斜型圈闭,油气保存条件好,成藏深;拉张型走滑转换带油气运移条件好,成藏浅,可分为张—扭转换区、拉张调节区和走滑单控区,张—扭转换区和走滑单控区多形成背斜、半背斜圈闭,拉张调节区多形成断块圈闭。

CHARACTERISTICS OF THE COMPRESSIONAL AND EXTENSIONAL STRIKE-SLIP TRANSFORM BELTS AND THEIR CONTROLLING ACTIONS ON THE HYDROCARBON ACCUMULATION FOR LIAODONG BAY DEPRESSION

Strike-slip transform belts possess obvious controlling actions on the hydrocarbon accumulation,the developed belts in Liaodong Bay Depression control the accumulation of the large and medium oil and gas reservoirs.With the help of the fine structural interpretations of 3D seismic data and integrated with the drilled achievements,the belts were subdivided into right lateral-left step-compressional strike-slip transform belt and right lateral-right step-extensional strike-slip transform belt,and moreover the controlling effects on the hydrocarbon accumulation of the two kinds of the belts were clarified.The researches show that the former belt can form a large amount of the anticline traps,which have the well-preserved conditions and deeper reservoir accumulation;while the later is characterized by the much better hydrocarbon migration conditions and shallower accumulation,and furthermore can be subdivided into extensional-torsional transforming zone,extension adjusting zone and single strike-slip-fault controlling zone.The former and latter are prone to form anticline and semi-anticline traps;while the middle is easy to generate fault block traps.