摘要
用相同pH值的碳酸水和硫酸水溶液对峰峰地区20种40块碳酸盐岩样品进行溶蚀试验。
Fengfeng region is bounded by Taihang mountains in the west and North China Plain in the east, covering an area of 2400km2. Stracturaily, the region is located at the southern part of the transitional zone between the rising belt of Taihang mountains and the subsidence belt of North China.The climate is temperate and semi-arid.The Middle Ordovician carbonate rocks extensively crop out in the region. The thickness of the Middle Cambrian and Ordovician carbonate rocks is about 1200m. The outcrop area of the carbonate rocks makes up about 1/2 of the total area of this region. The others are covered by the Cenozoic strata. In addition, there are odd pieces of outcropped Carboniferous and Permian strata.
We collect systematcally 20 kinds (40 pieces) of Ordovician carbonate rocks of the region. The samples are divided into two groups and respectively by the carbonated water and the sulphurated water with same pH value.Depending on the data of the dissolution test and the dissolution characteristics under electron microscope, we have studied the development mechanism and characteristics of the karst.The main results are as follows:
1.The main internal factor influencing the dissolution rate of the carbonate rocks is the mineral component of the rocks, the secondary factor is the structural genetic type. But the main factors influencing the development characteristics of karst morphology are the structural genetic type and the structure.
2.The reason that extensively distributed and intensively karstified brecciated limestone in North China becomes a relative aquiclude is honeycombed dissolution caused by the inhomogeneous structure of the rocks.
3.Unden the closed condition, the dissolution ability of the carbonated solution is three to five times more than that of the sulphurated solution with the same pH value, becuase the carbonated solution has greater dissolution potentiality.
4.The influence of containing a little magnesium on the dissolution rate of carbonate rocks is positive. This is the reason producing more dissolution of dolomite.
5. The sulphurated water is favourable to the dissolution of dolomite.
出处
《中国岩溶》
CAS
CSCD
北大核心
1992年第3期250-260,T003,共12页
Carsologica Sinica
关键词
碳酸盐岩
溶蚀
岩溶
发育
Carbonate rocks
Dissolution
Mechanism
Features
Fengfeng region,Hebei province
