The postglacial coastal sequences formed during the processes of trans-gression and regression with unconformity at the bottom.Two basic types ofpostglacial sequences in coastal zones of China have been distinguished.Theone in uplift belts consists of superimposed littoral facies

with underlyingbed being bedrocks or old Quaternary beds.The other one was formed indepressed belts

the lower and upper parts of whick are littoral facies with neritic one in between.Terrestrial stiff sand clay of dark green colour thataccumulated during low sea level is the underlying bed.The depressed beltspinched out progressively from coastline to continent

leading to superimposi-tion of lower and upper littoral facies

which then were replaced by terres-trial facies.The storm deposits are well developed in postglacial sequences and showvarious characteristics in different areas and sedimentary units.A few fora-minifera contained in dark green stiff sandy clay are considered as a resultof storm effect.Sand beds with shell fragments and glauconite are storm de-posits and are widely distributed in littoral facies at the northern flank of the Changjiang Delta.In neritic facies of the coastal sequences

the storm depo-sits are represented by sandy gravels with shell fragments in the coastal zones of Beibu(Tonkin)Gulf

and by sand layers that have lower inverse-graded bedding and upper graded bedding in the north flank of the Chang-jiang Delta.In tidal flat deposits of upper littoral facies

there are boulderclay and sand layer of 10-15 cm thick

which are also considered to bestorm deposits.The postglacial sequences in delta areas had been regarded to be conti-nuous without any serious erosion.The study of coastal sequences in deltaareas shows that the coastal sequences developed in ancient valleys and atinterfluve with strong tidal currents

such as Jianggang

often subjected toevident reworking.Only coastal zones where currents are usually weak

se-quences are continuous.