Physics and Chemistry of Dissolution on Subaerialy Exposed Soluble Rocks by Flowing Water Films
Physics and Chemistry of Dissolution on Subaerialy Exposed Soluble Rocks by Flowing Water Films
复制标题
流动水膜对暴露在地下的可溶性岩石溶解的物理和化学
DOI：
10.3986/ac.v36i3.169
复制
发表时间：
2007
期刊：
影响因子：
0.7
通讯作者：
G. Kaufmann
中科院分区：
文献类型：
--
作者：
W. Dreybrodt;G. Kaufmann
岩溶岩石陆上地貌形成的基本过程是石灰石或石膏被岩石表面流动的水膜化学溶解。在层流条件下，石灰石和石膏在水膜中的溶解速率由F = α（ceq-c）给出，其中（ceq-c）是水膜中的实际浓度c与相应矿物的平衡浓度ceq之差，而石膏的α由分子扩散决定，石灰石的情况更为复杂。实验结果表明，对于高欠饱和度，c = 0.3ceq。这些速率定律被用来计算裸露的岩石表面暴露于不同强度的降雨的剥蚀率。估计数与现场数据合理一致。从Glew和福特（1980）在石膏上进行的关于里伦岩溶缝形成的实验出发，我们提出了它们从顶部到“Ausgleichsflache”的长度与岩石表面倾角之间的新关系。这也适用于J. Lundberg和A.吉恩斯考虑到影响里伦卡伦形成的许多参数，这些相关性可以被认为是令人满意的。
The basic process active in the formation of subaerial features on karst rocks is chemical dissolution of limestone or gypsum by water films flowing on the rock surface. The dissolution rates of limestone and gypsum into thin films of water in laminar flow are given by F = α(ceq-c), where (ceq-c) is the difference of the actual concentration c in the water film and the equilibrium concentration ceq with respect to the corresponding mineral. Whereas for gypsum α is determined by molecular diffusion the situation is more complex for limestone. Experiments are presented, which show that for high undersaturation, c 0.3ceq. These rate laws are used to calculate denudation rates on bare rock surfaces exposed to rainfall with differing intensity. The estimations are in reasonable agreement to field data. Starting from the experiments on the formation of Rillenkarren on gypsum performed by Glew and Ford (1980), we suggest a new relation between their length from the crest to the “Ausgleichsflache” and the inclination of the rock surface. This is also applied to field data of Rillenkarren on limestone provided by J. Lundberg and A. Gines. In view of the many parameters influencing the formation of Rillenkarren these correlations can be considered as satisfactory.