酒东盆地营尔凹陷的扇三角洲

酒东盆地营尔凹陷中生界的扇三角洲相十分发育,其沉积作用活跃,流体类型丰富,主要以片状颗粒流沉积和片状牵引流沉积共存为特点。区内的扇三角洲沉积分布于紧邻盆地的活动的北部和东部边界断裂一侧,沉积相带发育齐全,由扇三角洲平原、扇三角洲前缘和前扇三角洲亚相组成,纵向上为下粗上细的退积型湖进层序,表明当时湖盆的沉陷速度超过了沉积补偿速度。扇三角洲相砂、砾岩与较深湖亚相暗色泥岩共生,加之中生界上部湖相泥岩和白云岩沉积连续,厚度较大,构成了一套完整的生储盖组合。

FAN DELTA IN YING'ER DEPRESSION,JIUDONG BASIN

Mesozoic fan delta facies in Ying'er Depression,Jiudong Basin developed well.It's sedimentation is brisk and fluid types are abundant.Sediments are mainly sheet grain flow deposit associated with sheet tractional deposit.The fan delta deposits in the region are distributed close to active boundary faults to the north and east of the basin.It's sedimentary facies belt,including fan delta plain,fan delta front and pre fan delta subfacies,developed completely.In vertical direction,the fan delta is a set of retrograding ingression lacustrine sequence with coarse sediments in the lower part and fine ones in the upper part,suggesting that subsiding velocity of lake basin surpassed sedimentary compensation velocity.The sandstones and conglomerates of fan delta facies and dark mudstone of deeper lake subfacies are paragenous in the region.In addition,sedimentary sequence of mudstone and dolostone of lake facies is continuous in Upper Mesozoic and its thickness is big.They constitute a set of complete source reservoir cap rock assemblages.