【摘要】 通过岩心精细描述及微相分析,研究了准噶尔盆地沙南断块侏罗系西山窑组四段(XS4)的沉积相和骨架砂体的微相特征。XS4砂层组自上而下可进一步划分出三个砂层XS41、XS42和XS43。其中,XS42和XS43的砂体发育,是一套三角洲前缘亚相为主的沉积,骨架砂体属三角洲前缘河口坝成因。河口坝包括坝顶和坝缘两种沉积类型。坝顶的砂层单层厚度大,泥岩夹层少;坝缘的砂层单层厚度小,泥岩夹层发育,向边缘砂层很快尖灭。更多还原

【Abstract】 On the basis of core description and microfacies analysis, this paper researches the sedimentary facies and microfacies characteristics of framework Sand member 4 of Jurassic system XiShanYao formation(XS4) in ShaNan fault-block area of Junggar basin.The member 4(XS4)can be divided into three sand layers from top to botomm ,that is XS41、XS42 and XS43. The sand body well developed in XS42 and XS43 ,which are mainly deposits of delta front facies.Its framework sand body was derived from distributary mouth bar of delta front facies.Two types of sedimentary facies can be discerned in the distributary mouth bar :central bar and marginal bar.The thickness of single sand body was bigger,mudstone interlayers were less in central bar,the thickness of single sand body was smaller, mudstone interlayers were more in marginal bar,and sandlayer pinching out rapidly towards side.更多还原