In order to fully understand the sedimentary characteristics of deltaic deposits and the development patterns of associated sand bodies
this paper presents a physical simulation of delta development through flume experiment and introduces the experiment results in respects of sedimentary process and characteristics of distributary channels
mouth bars
and slide-slump deposits. The experiment reveals that the development of delta is an alternating process of deposition and erosion. Deposition is dominant in flood season when distributary channels carry a heavy sediment load
while erosion is dominant in non-flood season. The growth of mouth bars initiates from an underwater shoal in an order of forward
upward
backward and transverse. In addition
there are two modes of bifurcation
i. e. multi-stage bifurcation by one mouth bar and simultaneous bifurcation by multiple mouth bars. The channels on a deltaic plain may evolve in two modes
i. e. redirection and diversion
which are related with flood and mouth bar respectively. Flood events could be the trigger of delta front slideslump deposits. Deltas are formed in the process of sediment transportation and sedimentation determined by the interaction of alluvial and basinal dynamics. In this process
sedimentary slope break is formed
which is favorable for the development of high quality reservoirs.
关键词
Keywords
references
张春生著.碎屑岩沉积模拟技术[M].石油工业出版社,2003.
姜在兴主编.沉积学[M].石油工业出版社,2003.
Chris Paola,Kyle Straub,David Mohrig,Liam Reinhardt.The “unreasonable effectiveness” of stratigraphic and geomorphic experiments[J].Earth Science Reviews,2009(1).
G. POSTMA,M. G. KLEINHANS,P. TH. MEIJER,J. T. EGGENHUISEN.Sediment transport in analogue flume models compared with real‐world sedimentary systems: a new look at scaling evolution of sedimentary systems in a flume[J].Sedimentology,2008.
D. B. Prior,Z. -S. Yang,B. D. Bornhold,G. H. Keller,N. Z. Lu,W. J. Wiseman,L. D. Wright,J. Zhang.Active slope failure, sediment collapse, and silt flows on the modern subaqueous Huanghe (Yellow River) delta[J].Geo-Marine Letters,1986(2).
高涛,李广雪,史经昊,刘杰.A flume test on erosion mechanism for an abandoned section of the Huanghe(Yellow)River Delta[J].Chinese Journal of Oceanology and Limnology,2010(03).