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由于受＂死碳＂的影响，年轻洞穴碳酸盐的~（１４）Ｃ测年始终受到限制，为此，建立了~（１４）Ｃ法测定石笋生长速率及校正＂死碳＂影响的理论模式，从而将石笋的测年时限和精度大大提高。这一理论成功地运用于北京石花洞年轻石笋的定年。利用~（１４）法与石笋生长光性年际纹层推算的平均生长速率十分吻合，表明石笋Ｓ３１２的生长速率为０．０４２ｍｍ／ａ。~（２１０）Ｐｂ法测定石笋顶部的年龄小于１００ａ，与~（１４）结果的外推年龄基本相同。这一研究结果为下一步解释稳定同位素的古气候意义奠定了年代学基础。运用~（１４）Ｃ法测定石笋生长速率要求有足够的数据点进行线性拟合。在线性范围内，要求满足石笋生长速率均匀，生长连续，＂死碳＂影响程度一致的假设条件。从δ~（１３）Ｃ和~（１４）Ｃ强度的对比分析，判断＂死碳＂的影响可能与气候变化有关。初步认为，湿冷气候条件下有利于石灰岩的溶解，造成＂死碳＂的影响增加。
Due to the influence of “dead carbon”, the ~ (14) C dating of young cave carbonates has always been limited. Therefore, the theory of ~ (14) C for determining the growth rate of stalagmite and correcting the influence of “dead carbon” Mode, which will greatly improve the dating time and accuracy of stalagmites. This theory has been successfully applied to the dating of young stalagmites at Shihuadong in Beijing. The ~ (14) method is in good agreement with the calculated average growth rate of photosynthetic interannual lamina in stalagmite growth, indicating that the growth rate of stalagmite S312 is 0.042mm / a. The age of the top of stalagmite determined by ~ (210) Pb method is less than 100 years, which is similar to the extrapolation age of ~ (14). The result of this study laid a chronological foundation for the next interpretation of the paleoclimate significance of stable isotopes. The ~ (14) C method for determining the growth rate of stalagmite requires that there be enough data points for linear fitting. In the linear range, it is required to meet the assumption that stalagmite growth rate is uniform, continuous growth, “dead carbon” consistent degree of influence. From the comparative analysis of δ ~ (13) C and ~ (14) C, it can be concluded that the influence of “dead carbon” may be related to climate change. It is preliminarily believed that the wet and cold climatic conditions are conducive to the dissolution of limestone, resulting in increased impact of “dead carbon.”