| 摘 要： | Tidal-flat and shoal deposits of carbonate facies in the Qiziqiao Formation are widely distributed over the vastareas of Guangxi,Guangdong and Hunan provinces,constituting an important stratigraphie unit where stratabound and sttatigorm ore deposits (galenite-sphalerite-pyrite) are. found,Thede types of ore deposits seem to have close relations to the tidal deposits. R ecognition of tho tidal sediments is based upon rock fabric, texture, strueture, fossil assemblage, and particular sedimentary cycles. The typical sequence of tidal-flat deposits consists mainly of three units: Amphipora limestone, laminated limestone and dalostone (from the bottom to the top).This sequence represents a complete process of sedimentation from low-tidal-flat through intertidal to high-tidal-flat or supratidah The sequence of shoal deposits of carbonate facies consists chiefly of grainstone and algal ooelsparite. Two major types of tidal deposits (open and restricted marine facies) can be distinguished, with eleven microfacies as follows: 1) grainatone with sparite (MF-1)[2) algal ooelsparite (MF-2); 3) onclite (algae-, or stromatoporoid-coated particles)(MF-3) ; 4) bioclastic grainstone or rudstone with sparite (MF-4); 5) Amphipora limestone (MF-5) ; 6) clark fossil-poor mierite (MF-6) ; 7) pelsparite or peloldal grainstone with sparite(MF-7);8)laminated pelleted mudstone-wackstone(MF-8);9)micrite with onkoids(MF-9);10)rudstone or floatstone(MF-10);and 11)bedding dolomite,gypsum-dolomite(MF-11).
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