吉林省松江盆地下白垩统大砬子组上段浊积岩沉积特征及地质意义

松江盆地为一中生代山间沉积盆地,盆地内大砬子组上段普遍发育浊流沉积。通过对浊积岩体的沉积环境特征、岩性特征、沉积构造特征、粒度结构特征及层序特征等进行的研究表明:发育于盆地扩张时期的大砬子组上段浊积岩具有稳定型浊积岩的沉积特征,并将其划分为中心微相及边缘微相。应用沉积岩碎屑物质成分对浊积岩进行统计并结合前人的研究成果表明,大砬子上段沉积时期,源区构造背景为稳定陆块区,构造环境较为稳定。大量浊积岩所形成的岩性圈闭可构成良好的储集体。

Turbidites from the upper member of the Lower Cretaceous Dalazi Formation in the Songjiang Basin, Jilin and their geological implications

The Songjiang Basin,Jilin is a Mesozoic intermountain basin where the turbidity current deposits are widespread in the upper member of the Lower Cretaceous Dalazi Formation.In terms of sedimentary environment,lithology, sedimentary structure,grain size and sequence,the turbidites in the upper member of the Dalazi Formation generated during the spreading phase of the basin are typical of stable turbidites,and may be discriminated into central microfacies and marginal microfacies.The tectonic setting of the source area belongs to the stable continental masses during the deposition of the upper member of the Dalazi Formation.The lithologic traps formed by the turbidites may be considered as excellent reservoirs.