陆相断陷湖盆迁移型层序构型及意义：以珠Ⅰ坳陷古近系文昌组为例
The Types and Implication of Migrated Sequence Stratigraphic Architecture in Continetal Lacustrine Rift Basin:An Example from the Paleogene Wenchang

相对于海相盆地层序，陆相盆地层序构型具有多样性特征．迁移型层序是陆相断陷湖盆演化过程中一种特殊的层序构型，研究相对较少．通过珠江口盆地珠Ｉ坳陷惠州凹陷、恩平凹陷古近系文昌组层序迁移现象的分析，定义了迁移型层序的概念，划分出“自迁移”和“异迁移”两种迁移型层序类型．自迁移型层序是由低角度正断层的水平滑动造成，即由同一条同沉积边界断裂控制；异迁移型层序由盆地两侧同沉积控边断裂活动强度及先后期次造成，即由两条同沉积边界断裂控制．迁移型层序在侧向迁移过程中，不同级次的层序地层单元控制下的储层、烃源岩也发生侧向迁移、斜列叠置，更利于生、储、盖等油气成藏要素的有效配置，形成多区块、多层段油气藏组合．
Compared with the sequences of marine basins, sequence stratigraphic architecture of non-marine basins is characterized by multi-variation and uncertainty. Migrated sequence stratigraphic architecture is one non-normal type in the evolution of continental lacustrine rift basin, which is rare documented. Based on the sequence stratigraphic units analysis of Paleogene Wenchang Formation of Huizhou and Enping sags, Zhu I Depression, Pearl River Mouth Basin, this paper defined the concept of migrated sequence stratigraphic architecture and divided into autogenic and allogenic migration. Autogenic migrated sequences are mainly controlled by horizontal displacement of low angle syndepositional normal fault, whereas allogenic migrated sequences are controlled by the different tectonic activation episodes of boundary fault on both sides of the basin. In other words, autogenic and allogenic migrated sequences are controlled by one and two syndepositional boundary fault, respectively. During the lateral migration of sequences, reservoirs and source rocks controlled by sequence stratigraphic units at multiple scales also migrate and stack laterally. This helps the high efficient configuration of hydrocarbon accumulation factors (e.g., source rock, reservoir, and seal) to generate reservoir combination with multiple blocks and multiple strata