英台断陷龙深2井区营城组二段储层预测

The Reservoir Prediction Of The Second Member Of Ying Cheng Formation In Long Shen2 Well Area,Ying Tai Fault Depression

松辽盆地英台断陷天然气储量丰富,北部龙深2井区含气储层下白垩统营城组二段为火山碎屑岩、沉积岩混杂堆积,储层分布杂乱。通过营城组二段的岩性、地震、测井等资料分析,认为营城组二段为火山沉积充填序列,区域火山作用与沉积作用同步,可划分为5个四级层序;物源主要来自三个方向,自西向东的沿控陷断裂上盘向下盘推进的物源,自北向南的长轴物源和区域火山间歇性喷发的点物源。结合储层反演及古地貌恢复手段预测出储层分布规律,在区域火山间歇期的C3、C4旋回储层受控于优势沉积相,而在区域火山喷发期的C1、C2、C5旋回储层主要受控于优势沉积相和盆地的古地貌特征。有利储层为辫状河三角洲、扇三角洲前缘以及受区域火山同沉积的古地貌洼地中的沉火山角砾岩、沉凝灰角砾岩、沉角砾凝灰质岩、沉凝灰岩。此次研究有效地预测了火山-沉积型盆地储层的分布规律,同时创新并拓展了层序地层学的应用范围,对同类的火山-沉积型盆地分析起到指导和借鉴作用。

The resource of natural gas is abundant in Yingtai fault depression,Songliao Basin and in it＇s north part LongShen2 well area gas- bearing reservoir is the second member of Yingcheng formation of Lower Cretaceous,with chaotic melange of pyroclastic rocks and sedimentary rocks and random reservoirs distribution. Based on the analysis of the data of lithology,seismic and logging and so on,it is found that the filling sequence of the second member of Yingcheng formation is volcanic- sedimentary type,with regional volcanism and sedimentation synchronized,which is divided into 5 four- stage sequences.There are mainly 3 source directions,the source from west to east and along the controlling- depression fault from upper wall to bottom wall,the long axis source from north to south and the point source in the intermittent eruption period of regional volcano. Combining reservoir inversion with ancient landscape restoration method,reservoir distribution is predicted that the effective reservoir of C3 and C4,which is in the intermittent period of regional volcano,is mainly controlled by preponderant sediment facies,while the effective reservoir of C1,C2 and C5,which is in the eruption period of regional volcano,is mainly controlled by preponderant sediment facies and the ancient landscape features of the basin. Favorable reservoir is sedimentary volcanic breccia,sedimentary tuff breccia,sedimentary breccia tuffaceous rocks and sedimentary tuff,which is in the braided river delta,the fan delta front and The ancient landform depressions in the eruption period of regional volcano. Through this research,reservoir distribution in volcanic- sedimentary basin is effectively predicted,Meantime,application range of sequence stratigraphy is innovated and expanded,which has great implication to identify and analyze volcano- sedimentary basin of the same type.