准噶尔盆地腹部地区白垩系呼图壁河组沉积特征

Sedimentary characteristics of Cretaceous Hutubihe formation in hinterland of Junggar Basin

以沉积学的方法和原理为指导,综合运用录井、测井、岩心、区域地质背景等资料,对准噶尔盆地腹部地区滴西12井区白垩系呼图壁河组沉积特征进行研究。结果表明:滴西12井区白垩系呼图壁河组岩性主要为灰色细砂岩、粉砂岩和棕红色泥岩的频繁互层,沉积相类型主要为干旱型砂质辫状河,微相类型主要有高能河道、低能河道、心滩、溢岸、河漫滩等,物源方向主要来自西北和东南方向;呼一段和呼二段共划分为14个小层;K1h18小层沉积初期发育西北向的辫状水道,K1h17～K1h15沉积时期辫状水道规模进一步扩宽,K1h14～K1h13沉积时期水流能量开始减弱,河道发育不明显,K1h12～K1h21沉积时期河道水动力条件又逐渐增强,河道不断分叉、合并和摆动,多期河道叠置,形成丰富的水道心滩储油砂体;沉积作用及不同类型沉积微相相带分布是研究区储层物性的主控因素。

Based on the principle and methods of sedimentology,the sedimentary characteristics of Cretaceous Hutubihe formation of Dixi 12 well block in Junggar Basin were analyzed by using well-logging,core data and the setting of this area.The results show that Hutubihe formation s lithologic character is fine sandstone,gray siltstone,argillaceous siltstone,brown mudstone alternate layers.Dixi 12 well block is arid braided river.And the microfacies are river channel,channel bar,embankment and flood plain.The source of the deposits comes from the northwest and southeast orientation.Hutubihe formation is divided into 14 substratas.The braided channels are mainly developed in K1h18 substrata.The braided channel becomes more and more wider in K1h17-K1h15 substratas.In K1h14-K1h13,the braided channel becomes weak.The braided channel becomes wider and separates in K1h12-K1h21 substrata,then forms a lot of sandstone bodies filled with oil.The sedimentation and facies belt distribution range of different sedimentary microfacies are main factors influencing reservoir performance of the study area.