THE EVOLUTION PATTERN OF THE YELLOW RIVER DELTA SYSTEM

The Yellow River delta is a highly constructive sedimentary system with fluvial action as its dominant external agency.It is a conjunction of three deltas:the ancient,the recent,and the modern deltaic system.It covers a subaerial area of approximately 10,000 km2.The rapid sand accumulation causes frequent avulsions and diversions of the lower-reach channels of the Yellow River.As a result,the delta protrudes deltaic coastline continuously seaward through the development of river mouth bars and spits,instead of building a Mississippi-type bird-foot delta.This river flows into the sea experiences following vicissitudes:the main river course diversion in the early period,disemboguement through single straight channel in the middle period,and the development into a meandering channel with frequent diversion and a lot of branches in the later period.