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中国云南路南是高原型喀斯特发育最为典型的区域之一，“石林喀斯特”最为著名。该区域喀斯特演化历史及其特点充分反映了云南东部地区在喜马拉雅运动期地壳活动的特征。石林喀斯特化过程中，形成了众多的钙质淀积物，包括河滩钙华、瀑布钙华、湖滩钙华、洞穴钙华及第三系硫酸盐岩。位于不同海拔高度的石林地貌及其间的洞穴钙华，代表了石林发育的不同阶段和过程：地壳抬升－溶蚀、侵蚀－再抬升、钙华沉积。湖滩钙华和河滩钙华的堆积特征也反映了这段历史。准确地确定钙华形成的年龄，便可详细研究石林地区石林喀斯特的演化历史，定量分析地壳抬升幅度和活动规律。作者在运用地质－地貌分析判别基础上，对钙质淀积物系统取样，采用电子自旋共振法（ＥＳＲ）测定钙华年龄，分别为：３１５．０６３万年、１３５．０２０万年、９２．２±１．６万年、３２．９±２．３—２７．０±１．４万年、１８．４±０．８万年、１４．２士０．２万年、７．９±０．４万年、４．８±０．５万年。据此确定了本区喀斯特演化的主要时期。经与大区域测年研究数据相比较，具有很好的一致性。这批数据的地质意义：（１）ＥＳＲ测年是研究钙华年代的有效方法；（２）定量研究石林喀斯特演化过程，构成溶蚀形态－沉积序?
South of Yunnan Road in China is one of the most typical plateau-type karst regions, and “Stone Forest Karst” is the most famous. The history and characteristics of karst evolution in this area fully reflect the characteristics of the crustal activity during the Himalayan movement in eastern Yunnan. During the karstification process of Shilin, many calcareous deposits have formed, including travertine, waterfall travertine, lake travertine, cave travertine and Tertiary sulphate. The stone forest landforms and cave travertine located at different altitudes represent different stages and processes of the development of the Shilin: crustal uplifting - erosion, erosion - re-uplift, travertine deposition. The accumulation of beach travertine and travertine also reflects this history. Accurately determine the age of travertine formation, we can study in detail the evolution history of Shilin Karst in Shilin area, and quantitatively analyze the crustal uplift amplitude and activity law. Based on the geological-geomorphologic analysis and discrimination, the authors sampled the calcareous sediment system and determined the age of travertine using electron spin resonance method (ESR): 315.063 million years, 135.0 million years , 92.2 ± 16,000 years, 32.9 ± 2.3-27.0 ± 1.4 million years, 18.4 ± 0.8 years, 14.2 ± 0.2 years , 7.9 ± 0.4 million years, 4.8 ± 0.5 million years. Accordingly, the main period of karst evolution in this area has been identified. Compared with the dating data in the large area, it has good consistency. The geological significance of these data: (1) ESR dating is an effective method for studying the age of travertine; (2) Quantitative study on the evolution of the Shilin karst forms the dissolution morphology-sedimentary sequence;