Based on the principles of seismic sedimentology and sequence stratigraphy

a high resolution sequence stratigraphy framework was established for the MFS18.5-SB17.5(K set)in Huizhou sag of Pearl River Mouth Basin with 8 sand layers or sand groups recognized.Based on the time-slices of seismic attributes under the constraint of sequence boundary surface

maximum flooding surface and the sub-flooding surface

we studied in detail the seismic facies and sedimentary facies in combination with the well logging and drilling data

cores and regional sedimentary backgrounds.Two depositional systems were recognized in K set of Zhujiang Formation in Huizhou sag

namely the river mouth bar of delta front-sheet sand depositional system in the west

and the shelf ridges system in the southeast.The shelf ridges are characterized by the follows:being located in the front of delta lobes;parallel to the coast in NEE direction

and in stripped distribution;and thinning towards to both edges.Some ridges are thick in one limb and having sharp edges

while the other limb thinning gradually and having irregular edges.This paper discussed the formation mechanism of those striped ridges on the shelf

and pointed out that the striped ridges were resulted from transportation and transformation of delta front sands by waves.And they laterally change into mudstone

thus are important domains for exploration of lighologic reservoirs.