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稳定同位素方法可以有效地应用于深水碳酸盐岩的成岩作用研究。根据早古生代中扬子台地东南缘斜坡带上碳酸盐岩的氧、碳稳定同位素特征，对几种成岩作用的环境因素和成岩机制进行了研究和探讨：（１）下奥陶统瘤状灰岩瘤体的δ１８Ｏ值均重于基质，证实了瘤状灰岩的早期雏形是灰泥沉积物经海底溶解胶结的反复交替作用而形成的；（２）下寒武统厚层状白云岩具有δ１８Ｏ和δ１３Ｃ值相对集中，且δ１８Ｏ略偏负的特点，而下奥陶统层状白云岩的δ１８Ｏ具有很高的负值，反映了二者分别是高盐度卤水流交代白云岩化和埋藏白云岩化的产物；（３）下奥陶统碳酸盐岩的不同岩石类型或不同结构组分均呈现１８Ｏ明显亏损，而１３Ｃ无明显变化的特征，说明受到了较强的埋藏重结晶作用的影响。
Stable isotope method can be effectively applied to the diagenesis of deep-water carbonate rocks. According to the characteristics of oxygen and carbon stable isotopes of carbonate rocks in the southeastern margin of the Yangtze platform in the Early Paleozoic, several diagenetic environmental factors and diagenetic mechanisms were studied and discussed: (1) The Lower Ordovician nodular gray The δ18O values of the rock masses are both heavier than that of the matrix, confirming that the early rudiments of the tuffaceous limestones are formed by repeated alternation of stucco sediments by seafloor dissolution-cementation; (2) the Lower Cambrian thick bedded dolomite has δ18O And δ13C values are relatively concentrated and δ18O is slightly negative. However, δ18O in the Lower Ordovician stratified dolomite has a very high negative value, reflecting that both are high-salinity brine flow metamorphosed dolomitization and burial clouds Lithology; (3) the different types of rocks or different structural components of the Lower Ordovician carbonate rocks show a significant loss of 18O, while no obvious change of 13C, indicating that they are strongly buried recrystallization influences.