沉积学报2025，Vol.43Issue(5)：1625-1641,17.DOI:10.14027/j.issn.1000-0550.2025.051
沉积物重力流搬运演化与沉积过程
Transport,Evolution and Depositional Processes of Sediment Gravity Flows
摘要
Abstract
[Significance]Deepening the understanding of the transport evolution and depositional processes in sedi-ment gravity flows is the best way to achieve the effective resolution of debates on terminology and to establish stan-dard expressions describing sediment gravity flows.[Progress]The transformation between supercritical and subcriti-cal turbidity currents is a key dynamic property of sediment gravity flows in relatively proximal depositional settings.Such transformation may occur either as a result of hydraulic jumps,or via self-organized evolution that is indepen-dent of hydraulic jumps.Flow dilution is constrained by gravity transformation or by surface transformation,either of which may determine the transition from high-concentration debris flows into low-concentration turbidity currents.Dif-ferent transport and settling processes in debris flows and turbidity currents,along with the suppression of turbulence by mud content,are the primary driving mechanisms of the transformation of turbidity currents into muddy debris flows.Erosion of muddy substrates by a supercritical turbidity current increases mud content and transforms it into a muddy debris flow,and may also form hybrid-event beds.Transitional gravity flows are significant components of hy-brid gravity flows.Flow efficiency in gravity flows is the core factor that determines the differences in transport evolu-tion and in the deposition of sediment.Transformation between supercritical and subcritical turbidity currents primari-ly occurs in relatively proximal channelized hyperconcentrated density flows,and in gravelly,high-density turbi-dites,in the channel-lobe transition zone.The transformation of turbidity currents into muddy debris flows,on the other hand,mainly occurs in relatively distal,lobe-associated,sandy,high-density turbidites and deep-water,plain,low-density turbidites.[Conclusions and Prospects]Recent insights into the transport evolution and deposi-tional processes of sediment gravity flows further enrich the perceptions of process sedimentology by providing a theo-retical basis for rationally interpreting the origination of gravity flow sandbodies and similarly debated issues;further,they highlight the critical importance of outcrop sedimentological studies.关键词
沉积物重力流/超临界流/混合重力流/过渡型重力流/流体演化/沉积过程Key words
sediment gravity flow/supercritical flow/hybrid gravity flow/transitional gravity flow/flow evolution/depositional processes分类
天文与地球科学引用本文复制引用
杨田,操应长,田景春,蔡来星,刘蓥霖,崔蓉,朱忠华,罗星兰..沉积物重力流搬运演化与沉积过程[J].沉积学报,2025,43(5):1625-1641,17.基金项目
国家自然科学基金项目(42372139) （42372139）
四川省杰出青年科学基金项目(2025NSFJQ0004) （2025NSFJQ0004）
四川省科技教育联合基金面上项目(2024NSF-SC1993)National Natural Science Foundation of China,No.42372139 （2024NSF-SC1993）
Sichuan Province Outstanding Youth Science Founda-tion,No.2025NSFJQ0004 （）
Sichuan Province Science and Technology Education Joint Fund General Project,No.2024NSFSC1993 （）
