准噶尔盆地侏罗系辫状河三角洲沉积特征

Sedimentary characteristics of the shallow Jurassic braided river delta,the Junggar Basin

朱筱敏 张义娜 杨俊生 李德江 张年富

Zhu Xiaomin Zhang Yina Yang Junsheng Li Dejiang Zhang Nianfu

辫状河三角洲是陆相沉积盆地重要的油气储集类型和今后油气勘探的重点对象.综合分析岩心、测井与地震资料,认为准噶尔盆地侏罗系三工河组发育的辫状河三角洲处于沉积坡度较缓的、沉积水体较浅的沉积背景,该辫状河三角洲不断地由盆地北侧边缘向盆地中央方向远距离前积,沉积了砂砾质的、发育大型交错层理和间断正韵律的、具有典型前积地震反射的进积型辫状河三角洲,进而论述了该三角洲的亚相和微相沉积特征以及有利的地层岩性圈闭勘探地区.

Braided river delta is an important reservoir type in continental sedimentary basins and the potential exploration target for the future.Core,log,and geophysical data indicate that the braided river delta in the Jurassic Sangonghe Formation of Junggar basin was deposited in an environment with gentle slope and shallow water.As a result of continuous progradation from the north to the center of the basin,arenaceous-conglomeritic deposits in the delta showed typical progradational seismic reflectance signatures,large cross bedding,and non-continuous positive rhythm.Its characteristics of sedimentary subfacies and microfacies as well as the favorable areas for exploration of lithologic traps are also discussed in this paper.

10.11743/ogg20080214