泌阳凹陷北坡下切谷—低位扇沉积体系及其油气勘探意义

Eroded valley-topogenetic lowstand fan sendimentary system in north slop of Biyang depression and its significance in oil and gas exploration.

杨道庆 ,邱荣华 ,赵追 ,姜在兴 .泌阳凹陷北坡下切谷—低位扇沉积体系及其油气勘探意义 .石油地球物理勘探 ,2 0 0 2 ,37(5 ) :4 85～ 4 90 通过层序地层学研究 ,在泌阳凹陷北部斜坡带孙岗地区下第三系核桃园组中识别出 4个三级层序 ,其中在层序 、层序 低位域中识别出下切谷—低位扇沉积体系。下切谷充填物在地震反射结构、沉积结构、沉积序列等方面都具有显著的特征 ,文中总结出该区缓坡扇三角洲平原—下切谷—低位扇沉积体系的沉积模式。断陷陆相湖盆边缘地带发育的下切谷在成因上有自身的特点 ,其形成受到构造沉降和湖平面下降的共同影响。研究下切谷、低位扇对隐蔽油气藏勘探具有非常重要的实际意义 ,文中还指出与该层序模式相关的 4种油气藏。

Through sequence stratigraphic research,four sequences in third grade were identified in the Hetaoyuan Formation of Lower Tertiary in Sungang area,north slop of Biyang Depression,among which a eroded valley topogenetic lowstand sedimentary system was recognized in the lowstand tracts of sequence Ⅱand Ⅲ.The deposits in the eroded valley have specific feature in seismic reflection structure,sedimentary structure and depositional sequence.The paper presents the sedimentary mode of ramp fan delta plain eroded valley topogenetic lowstand fan sedimentary system.The eroded valley developed on the boundary of the continental fault lake basin has specific genetic features and its formation was controlled both by structural subsidence and lowering of lake surface.The research on eroded valley and topogenetic lowstand fan has outstanding significance on exploration of subtle reservoirs.There are 4 kinds of oil and gas reservoirs related with this sequence mode that were pointed out in the paper.