准噶尔盆地腹部三工河组二段沉积微相分析

Sediment facies of the second sect of the Sangonghe formation in hinterland of Zhunge'er basin

准噶尔盆地腹部主要勘探目的层为侏罗系下统三工河组二段. 其沉积环境不仅发育辫状河三角洲,而且发育曲流河三角洲和浊流沉积. 辫状河三角洲前缘亚相以水下分流河道与分流间的频繁叠置为特点,河口砂坝微相不太发育,而浊流为三角洲前缘滑塌沉积所至. 三工河组二段下亚段以辫状河三角洲沉积为主,而其上亚段随着湖侵,发育曲流河三角洲沉积.

The second section of Sangonghe formation is an important oil-bearing layer in hinter-land of the Zhunge'er basin. Three types of sediment facies have been analyzed in this paper: delta, lacustrine and turbidity current. Meanwhile, two types of delta-braid delta and meandering delta are recognized. The important character of braided delta is that the amount of sandstone has been developed while the estuarine bar is not. It is found that braided delta is the main sediment facies in the period of the second section of Sangonghe Formation and meandering-delta is the main sediment facies of the first section.