地层岩相组合有规律地分布于层序的不同体系域。为了有效地进行储层发育、烃源岩分布的预测,文中提出层序构型的明确概念、类型、识别标志及其意义。层序构型是指三级层序内不同体系域地层单元时间-空间组成配置关系,其类型可分为L型、T型、TH型、H型(E-H型和L-H型)4种,其中,L型层序主要为富砂层序,储层相对发育;T型层序为富泥层序,烃源岩最为发育;TH型层序为富泥层序,烃源岩相对发育;E-H型层序为富泥层序,烃源岩发育程度次于TH型层序;L-H型层序主要为富砂层序,储层相对发育。珠江口盆地富烃的惠州凹陷文昌组层序构型实例分析表明,惠州凹陷南缘主要为T型层序,烃源岩相对发育,北缘主要为H型层序,储层相对发育。
Stratigraphic lithofacies assemblages are regularly distributed within different system tracts of the sequence stratigraphic framework.The present paper deals with the concept,types,recognition criteria and implications of sequence stratigraphic architecture in order to effectively predict the development of reservoir and the distribution of hydrocarbon source rocks.Sequence stratigraphic architecture can be defined as the temporal and spacial relationship of the system tracts within the sequence stratigraphic framework.The types of sequence stratigraphic architecture include type L,T,TH and H with subtypes of E-H and L-H.Type L sequence is usually characteristic of sand prone lithofacies with excellent reservoir properties;type T sequence is typical of shale-rich lithofacies containing excellent hydrocarbon source rock;both type TH and subtype E-H are shale-rich lithofacies but subtype E-H developes less hydrocarbon source rocks than the type TH,and subtype L-H is characteristic of sand prone lithofacies with relatively developed reservoirs.As illustrated by using the sequence stratigraphic architecture of Wenchang Formation in the Huizhou hydrocarbon-rich sag,Zhujiangkou Basin,it is showed that the type T sequence acts as the excellent hydrocarbon source rock in the southern margin of the Huizhou sag,and the type H sequence is the good reservoir in the northern margin of the Huizhou Sag.