中文摘要：

萎缩期是陆相湖盆演化的重要阶段，但和断陷期、坳陷期相比，对湖泊萎缩期的沉积充填和层序构成的认识非常不足，研究也非常薄弱。松辽盆地的四方台期和明水期是典型的湖盆萎缩期，对其沉积充填和层序构成的研究有助于加深学术界和工业界对这一重要阶段的认识和促进油气勘探。将四方台组、明水组划分为一个超层序，六个三级层序。对比分析了松辽盆地坳陷期与萎缩期地质特征，认为盆地萎缩期为地形平缓的浅水盆地，具有构造幅度低、可容空间小、湖平面升降频繁等特点。层序界面多表现为低角度不整合、低幅上超面以及沉积转换面等；沉积上，该段主要发育河流相、浅水湖泊、浅水三角洲等沉积相。层序结构上，由于没有明显坡折带，故采用两分法划分体系域，包括湖侵体系域（TST）和湖退体系域（RST）；盆地边缘没有明显的的下切谷特征，砂体主要发育于湖侵体系域，很少发育湖底扇。从层序主控因素看，由于构造整体稳定，湖平面变化主要受气候和盆地古地貌影响。

英文摘要：

The shrinkage stage is an important part of basin evolution. The research actuality about the sequence stratigraphy of rift basin among faulting stage, depression stage and shrinkage stage shows that there is very little systematic research about the sequence stratigraphy during shrinkage stage, and there is vague understanding of its sequence boundary, structure, and main control factors. In the view of this problem, we carried out a systematic research about the sequence stratigraphy in Sifangtai formation and Mingshui formation which correspond to the shrinkage stage in Songliao basin. One supersequence was defined by two regional unconformities, and it can be divided into six sequences. The comparison and analysis on the geologic feature between depression stage and shrinkage stage in Songli ao Basin shows that it is a shallow lake with smooth topography, and its representative characteristics are low-amplitude structure, low accommodation space, frequently up and down of base level, and so on. The representative characteristics of sequence boundary are gentle angular unconformity, low-angle on-lap and transfer surface between ascending and falling. The sedimentary facies of this region contain meandering river, meandering river delta, braid river delta, lakes and so on. In their sequence structure, they were divided into two system tract： transgressive system tract and regressive system tract. There is no obvious incised valley in basin margin and few sub-lacustrine fan was found. Sands are mainly in the transgressive system tract. Because of stable structural setting, sequences were controlled mainly by palaeoclimate and palaeotopography.