百色盆地那读组短期基准面旋回层序分析

以高分辨率层序地层学理论和技术方法为指导，运用短期基准面旋回界面的识别标志将百色盆地那读组短期基准面旋回层序划分为向上“变深”的非对称型（A 型）、向上变浅的非对称型（B 型）、向上变深复变浅的对称型（C型）等三种基本结构类型，再根据可容纳空间大小和上下两个半旋回的厚度进一步划分为七个亚类型:即低可容纳空间向上“变深”的对称型（A₁型），高可容纳空间向上“变深”的非对称型（A₂型），低可容纳空间向上变浅的非对称型（B₁型），高可容纳空间向上变浅的非对称型（B₂型），完全-近完全对称型（C₁型），以上升半旋回为主的不完全对称型（C₂型），以下降半旋回为主的不完全对称型（C₃型）。文中详细讨论了每个基本类型和亚类型的沉积背景、叠加样式、岩性组成和沉积动力学过程，并指出有利储集砂体在每种类型中的发育部位。在此基础上，总结了短期基准面旋回层序的变化规律和分布模式，指出从陆地向湖盆，短期基准面旋回层序类型具有从A₁型!A₂型!C₂型!C₁型!C₃型!B₁型!B₂型的变化规律，并简述了短期基准面旋回层序在油气勘探开发中的研究意义。

Short-Term Base-Level Cycle Sequence Analysis of Nadu Formation in Baise Basin

According to the identification mark of the short-term base-level cylce interface and under the guidance of the theory and technology of the high-resolution sequence stratigraphy, the authors divide the short-term base-level cycle of Nadu Formation in Baise Basin into three basic structure types which are up-deepening non-symmetry, up-shallowing non-symmetry and symmetry from up-deepening to up-shallowing. Furtherly in the light of the high or low accommodation, and the thickness of the uprising periods and subsiding periods of the short-term base-level cycle, seven subtypes of structure are distinguished and they are up-deepening non-symmetry of low accommodation (Type A₁) or high accommodation(Type A₂)up-shallowening non-symmetry of low accommodation (TypeB₁) or high accommodation (Type B₂)complete～nearly complete symmetry (Type C₁)in complete symmetry with the majority of uprising semi-cycle(Type C₂) or subsiding semi-cycle(Type C₃).In this paper the sedimentary environment,stacking patterns,lithlolgic association and sedimentary dynamic processes of each basic type and subtype of structure is discussed in detail. And the development position of the advantage reservoir sand body in each structure type are pointed out. On the basis of these studies, the change rule and distribution pattern of the short-term base-level cycle sequence are summarized. From the terrigenous to lacustrine environment, the short-term base level cycle sequence types have the change rule that is in succession from Type A1 to Type A₂, then to Type C₂, to Type C₁ Type C₃ Type B₁ and at last to Type B₂.In the structure types of short-term base-level cycle sequence, the advantage reservoir sand body mainly develops in Type A₁, secondly in Type A₂Type B₁ and Type C₁. In this paper, the authors also briefly discuss the application of the short-term base-level cycle sequence in oil and gas exploration and development stage.