The characteristics of sediments

such as their sequences

particle-size dis-tribution

constituents of minerals and detritus and the surface features ofquartz grains

are discussed here with respect to environments relative to the upper tributaries

braided channels of the upper-middle reach

meander-ing channels of the middle-lower reach and the deltaic distributary-monthbars within the system of Luan drainage

as well as to the coastal beach

the coastal dume and the beach of the Beidaihe cliffed coast.This study shows that sediments from individual environments mentioned above are different and

therefore

their features can be used for identifying environments of sedimentation.The diverse environments are characterized by apparent different cumulative probability curves.The constituents of minerals and detri-tus derived from the same source area are functions of transport distance andcurrent agent

especially when they are of unhomogeneous nature.The surfacefeatures of quartz grains are indicative of environments of sedimentation

e.g.of aeolian

marine and fluvial conditions.This study suggests that Luanriver is a middle-small

seasonal and sand-rich one of short source.There-fore

its sediments are abundant in sands with only a few of mud interca-lations.The sand grains is coarse and

in addition

there are gravels andmud gravels at the base of section

the content of minerals is less than thatof detritus

with maturity being lower.The dune is well deveoped on banksof the stream and this demonstrates that the wind may be strong enough during the dry season.The delta is resulted primarily from the agent ofstream

but certain tidal action may also be involved.The sediments on the beach near the Luan river mouth are distinct from that on the beach ofBeidaihe cliffed coast due to the distinction between them.