基于钙均衡估算黄龙钙华沉积速率的探讨

Evaluation to the deposition rate of Huanglong travertine by calcium ion equilibrium

从黄龙钙华的成因研究出发,结合地质历史分析及长观资料对核心景区景观水系统的相对稳定性作出了评价。通过对景观水中钙离子及其它组分含量在时间及空间上变化特征的分析研究,揭示了钙离子含量在时间上的相对稳定以及在空间上自上游而下逐渐降低的规律,这为采用钙均衡模式来研究钙华堆积区内的年沉积量提供了重要保证。在此基础上,进一步通过同位素测年、物探、测绘等综合手段对钙华堆积区内的历史与现代的平均沉积速率进行系统研究,并与前人的研究成果对比,验证了钙均衡模型的可行性和可靠性。计算结果表明,黄龙核心景区钙华的平均沉积速率为1～4.86mm/a。

On the basis of the study to the genesis of Huanglong travertine and analyses to geo-history as well as long-term observation data, the relative stability of hydrological system at the center of the Huanglong scenic spot is evaluated in this paper. Through studying to temporal-spatial variation of the contents of calcium ion and other components in the water, it is proved that the calcium ion is relatively stable temporally and decreases gradually towards the lower reaches. This situation can provide good conditions for studying the depositional rate of the Huanglong travertine by using calcium ion equilibrium model. Further, through comprehensive methods involving isotopic dating, geophysical exploration and mapping, the average annual depositional rate in history and at present is studied systematically. In comparison with former studies, the feasibility and reliability of calcium equilibrium model is confirmed. This study proved that the average depositional rate of travertine is 1～4.86mm/a at the center of the Huanglong scenic spot.