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位于中国南沙群岛中的美济礁是由珊瑚礁环围绕泻湖形成的.在珊瑚构成的礁环上既有突起的小珊瑚岛(在礁环上的小补丁礁)也有低缓的礁沙丘,微生物碳酸盐沉积发育在环礁底部周围和斑块礁塔的珊瑚上或礁沙丘的珊瑚断枝上,生长形式主要为绒毛状、发状或细刺状、胶块状、席状或结壳状,一般发育在0～15m水深环境中.这些微生物沉积可能是由丝状蓝菌的自然种群经钙化后形成.它们的生长位置:(1)与Acropora共生的球茎状珊瑚上;(2)块状的Galaxea fascicularis丛体上;(3)死亡的Montipora digitata丛体上;(4)死亡的Acropora teres上,一些发状的微生物碳酸盐沉积覆绕这些珊瑚断枝生长.研究证实了微生物碳酸盐沉积在中国南海珊瑚礁沉积中的发育,显示出微生物作用过程在现代珊瑚礁系统形成中的重要性.其研究结果对确定地质时期形成微生物岩(microbialite)的微生物的特征和成分,以及对评估现代珊瑚礁中的微生物碳酸盐沉积及其在现代礁系统生物化学循环中的重要性都具有重要意义.研究结果还提供了地质时期浅水环境中形成的古微生物岩现今类比的证据,并且结合古微生物岩的沉积学研究来了解其生长控制机理.
The Meiji Reef in the Nansha Islands of China is formed around a lagoon surrounded by coral reefs, with small, promontory coral reefs (small patch reefs on the reef ring) and low reef dunes, microbial carbonate Salt deposits are developed on the corals or on the reef dune coral branches around the bottom of the atolls and the patch reefs. The growth patterns are mainly villous, hairy or thin thorns, plastic lumps, seats or crusts, Generally developed in the depth of 0 ~ 15m water environment.These microbial deposition may be formed by the natural population of filamentous filamentous calcification after the formation of their growth position: (1) and Acropora symbiotic bulb-shaped coral; (2) lump Of Galaxea fascicularis, (3) the death of Montipora digitata, and (4) the death of Acropora teres, with some hairy microbial carbonate deposits surrounding the growth of these coral snails. The study demonstrated that microbial carbonates The development of salt deposits in the coral reef sediments of the South China Sea shows the importance of microbial processes in the formation of modern coral reef systems. The results of this study are useful in determining the characteristics and composition of microorganisms that form microbialites during geologic times , As well as for the assessment of microbial carbonate deposition in modern coral reefs and their importance in the biochemical cycle of modern reef systems.The findings also provide evidence of today’s analogies of paleoclimate rocks formed in shallow-water environments during geologic times , And combined with the study of sedimentology of ancient microbial rocks to understand its growth control mechanism.