Abstract:

Green grains in the Yangtse River mouth area can be classified into threegroups:granular,sheet-like and test-mould.The grains are mainly authigenesis in neritic facies.They may occur inother non-marine sedimentary facies such as channel,recent sedimentary areaand sea shore lake basin bog in lower reaches of the river due to the trans-portation of waves,tidal currents and storms.The grains in the relict sedi-mentary areas and in the recent sedimentary areas on the continental shelfare abundant and sheet-like and test-mould particles developed well.The abundances of the green grains in the recent sedimentary areas of the Yangtse River Mouth changes greatly.They may be much higher in deep channels,while much lower in fast-depositing areas where the dynamic condition ismuch weaker.The grains may be carried into typical limnic facies by storm sbut the abundances of those are much lower and the particles are mostly black ovoid.