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在早上新世,沿挪威中部大陆架发育了广泛的三角洲和海岸进积沉积体。在多次覆盖地震资料上的三角洲复合体中识别出了38个发育良好的高频(四级)层序。这些四级层序可整理为四个倾斜型进积层序组和两个S型进积层序组。高频层序的沉积和它们的叠加模式可能是叠置于低频海平面变化体系中的高频全球海平面升降周期之上的、由构造升降速率变化产生的海平面周期中相对海平面变化的高频周期的响应。加积/进积混合型层序组被认为代表了新增可容空间速率的增加和三级层序HST之内的沉积作用;相反,进积层序组代表新增可容空间速率的减小和三级层序的LST之内的沉积作用。多个层序组的识别可能反映了长期的海平面相对下降(构造抬升?)叠加于高频全球海平面变化周期之上的影响。层序组的顶界形成于相对海平面变化曲线上三级下降拐点和四级下降拐点的交汇处,这些层序边界代表最大陆上剥蚀的时期,同时可能代表储集砂体沉积的最有利时期。
In the early Pliocene, extensive deltaic and coastal sedimentary deposits were developed along the central Norwegian shelf. Thirty-eight well-developed high-frequency (quaternary) sequences were identified in the delta complex overlying the seismic data. These four-level sequences can be organized into four slanted-type progressive sequences and two S-type sequences. The deposition of high-frequency sequences and their superimposition patterns may be superimposed on the high-frequency global sea level rise-and-fall cycle in the low-frequency sea level change system, which is caused by the relative sea level change in the sea level period High frequency cycle response. The accretionary / accretionary mixed sequence group is considered to represent an increase in newly-added space velocity and deposition within the third-order sequence HST; on the contrary, the programed sequence group represents a decrease of newly-added space velocity Sedimentation within the LST of small and tertiary sequences. The identification of multiple sequence sets may reflect the effect of the long-term relative sea level decay (tectonic uplift?) Superimposed on the HF global sea level change cycle. The top boundary of the sequence group is formed at the intersection of the third-level inflection point and the fourth-level inflection point on the relative sea level curve. These sequence boundaries represent the period of the largest onshore denudation and may represent the most favorable deposition of reservoir sand bodies period.