泥岩底辟型微盆地中的深海浊积朵叶沉积系列构型模式及控制因素

Deep-sea turbidity lobes are recognized as high production reservoir in deep sea sediment. However, as of now we don't know much about sedimentary architecture series models, control factors and action mechanism of them, for their sedimentary architecture styles are complicated, and this increased the drilling risk. The project, taking the shallow-layer high resolution 3D seismic data of Niger Delta continental slop as a example, will focus on the control factors and its action mechanism of sedimentary architecture of deep-sea lobes by the combining method of quantitative seismic geomorphology and sedimentary architecture analysis. It will discuss geometries and patterns of deep-sea lobes with different hierarchical scales, and establish their corresponding architecture models. On this basis, we want to reveal the internal controlling factors and action mechanism of lobe sedimentary architecture unites by measuring and analying geometry parameter of deep-sea lobe architectural unites quantitatively. In addition, terrain slope which can reflect the relief of lobe elements will also be surveyed, and the coupling and connection of slope with geometry ones of deep-sea lobe will be made. And then the external controlling factors and action mechanism to deep-sea lobe depositional pattern will be further studied.

深海浊积朵叶被公认为深海沉积中的高产储层，然而，其沉积构型样式复杂多变，当前尚未揭示其沉积构型系列模式、主控因素及作用机理，这大大增加了该类油气藏钻探风险。为此，本项目拟以尼日尔三角洲陆坡区典型泥岩底辟型微盆地深海浊积朵叶沉积为例，基于浅层高频地震信息，结合沉积构型理论和定量地震地貌学方法，进行地震地貌平面和剖面构型分析，建立深海浊积朵叶内部不同层次构型单元（朵叶体系、复合朵叶和单一朵叶）沉积构型系列模式；在此基础上，测量深海浊积朵叶几何形态定量控制参数，并分层次分析其相互关系，探究深海浊积朵叶构型发育的内部控制因素及作用机理；此外，测量能反应沉积前的地形坡度等参数，结合朵叶几何形态定量控制参数相互关系分析结果，探究地形坡度和地貌形态与其之间的耦合和关联，揭示朵叶构型发育的外部控制因素及作用机理。

本项目以尼日尔三角洲盆地陆坡区典型泥岩底辟型微盆地为例，基于尼日尔三角洲陆坡泥岩底辟区浅层高频三维地震资料，以受构造活动、差异压实影响较小的近海底高频地震信息为原型，以较短流动距离内（约18km）平面形态多变的深水沉积体系（BSDS）为例，进行了地震属性提取和时深转换，提取了能反映浅层地貌特征的地震属性，开展了地震层序构型研究，对研究区层序地层进行分析，追踪解释了H1-H5五个地震层位；对深海浊积朵叶层序地层格架进行构建，对朵叶复合体（lobes）、线状水道系列（straight channels）和裙状朵叶复合体（Slope aprons）等三个层次的沉积构型单元进行了特征分析和地震追踪解释；对地震地层特征、生长断层特征和微型盆地分布进行了分析；对不同层次的朵叶沉积进行了解剖，对发育于微型盆地I 和微型盆地II中的朵叶A和B，测量了朵叶体、复合朵叶层次及连通河道的定量化参数，并基于测量结果进行了分析，对主要的控制因素进行了探讨。