深海水道迁移模式及成因机制

Migration Patterns and Genetic Mechanisms of Deep-sea Channels

梁诗琴 吴伟 向威 赵中会 随雅萍

LIANGShiqin WUWei XIANGWei ZHAOZhonghui SUIYaping

中海油田服务股份有限公司, 河北 燕郊 065201 河南理工大学资源环境学院, 河南 焦作 454003 海南省深海深层能源工程重点实验室, 海南 澄迈 571900

China Oilfield Services Limited, Yanjiao, Hebei 065201, China School of Resources and Environment, Henan Polytechnic University, Jiaozuo, Henan 454003, China Hainan Province Key Laboratory of Deep Sea and Deep Layer Energy Engineering, Chengmai, Hainan 571900, China

深海水道是陆源碎屑沉积物向深水盆地输送的重要通道之一，同时也是深水盆地中砂体沉积的主要场所，广泛发育于全球范围内的被动大陆边缘。为了厘清深海水道迁移与成因机制，对过往研究进行总结，得出以下结论：根据迁移方式可将深海水道分为单向迁移水道(上游迁移型和下游迁移型)和多向迁移水道(顺流迁移型、侧向迁移型和障碍迁移型)；可依据水道深泓线变化对水道迁移特征进行具体表征，单向迁移水道发育伴随深泓线整体变化，多向迁移水道则主要为局部变化；底流与重力流的交互作用控制单向迁移水道的沉积建造，此外自身环流以及上升流作用也影响水道的沉积演化，多向迁移水道则受海平面升降、物源供给、构造运动、古地形与水道自身沉积作用等多种因素共同控制。未来深海水道迁移模式研究和发展方向主要包括3个方面：1)积极开展多尺度的定量化研究；2)深入探究各种动力学因素耦合关联的水道迁移机制；3)加强对水道迁移模式与储层开发的关联研究。

The deep-sea channel is one of the important conduits for the transport of terrestrial clastic sediments to deep-water basins, and it is also the main depositional site for sand sedimentation in deep-water basins.This study summarizes previous research to clarify the migration and formation mechanisms of deep-sea channels, yielding the following findings: based on the migration mode, deep-sea channels can be categorized into unidirectional migration channels (upstream migration type/downstream migration type) and multidirectional migration channels (downstream migration type/lateral migration type/obstacle migration type). The migration characteristics of the channels can be characterized based on the changes in the channel thalweg, unidirectional migration channels are accompanied by overall changes in the thalweg line, while multidirectional migration channels primarily exhibit local changes. The interaction between bottom currents and gravity currents controls the sedimentary construction of unidirectional migration channels. In addition, self-circulation and upwelling currents also affect the sedimentary evolution of the channels. Multidirectional migration channels, on the other hand, are controlled by multiple factors such as sea level changes, sediment supply, tectonic movements, paleo-topography, and the sedimentary action of the channels themselves. The formation of unidirectional migration channels is mainly controlled by the interaction between gravity flows and contour currents, the self-circulation of flows, and upwelling flows, while multidirectional migration channels are mainly influenced by sea-level changes, sediment supply, tectonic movements, paleotopography, and the self-deposition of channels. The future research and development directions of deep-sea channel migration patterns mainly include three aspects: 1) actively conducting multi-scale quantitative research; 2) exploring the coupling mechanisms of various dynamic factors related to channel migration; 3) strengthening the research on the relationship between channel migration patterns and reservoir development.

10.11885/j.issn.1674-5086.2024.08.31.02