Limestone is mainly formed in the shallow sea environment. Limestone can be divided into granule limestone (flowing water, sediment formation) according to genesis; bio-skeletal limestone and chemical and biochemical limestone. According to the structural structure, it can be subdivided into bamboo-like limestone, limestone, and agglomerated limestone. The main chemical component of limestone is calcium carbonate, which is easy to dissolve. Therefore, stone forests and caves are formed in the limestone area, which is called karst topography.
Limestone generally contains some dolomite and clay minerals. When the clay mineral content is 25%~50%, it is called argillaceous rock. When the content of dolomite reaches 25%~50%, it is called dolomitic limestone. Limestone is widely distributed and has uniform lithology and is easy to be mined and processed. It is a widely used building material.
The main component of limestone is calcium carbonate, which can be dissolved in water containing carbon dioxide. In general, one liter of water containing carbon dioxide can dissolve about 50 mg of calcium carbonate.
According to a survey by geologists in the Guilin area, it was found that the water there dissolves and erodes the surface of the limestone about a thin layer of nails. Don't look at only a little bit of erosion every year, but the history of earth development is extremely long. In the recent geological period, the Quaternary, there were about 3 million years.
Even with such a slow dissolution rate, it can dissolve 900 meters in 3 million years! The lonely peak of Guilin is only one or two hundred meters high, and the maximum height of common caves is only tens of meters. However, it is not the place where limestone can form such a topography. Instead, it needs a large area, large thickness, and geologically pure limestone. It also requires warm and humid climatic conditions to develop into such a perfect landform. Beautiful natural scenery.
Plastic Stylus Touch Pen For Nintendo New For 3DSXL& for NDSiXL for DSI DSL Black,Clear Anti Scratch Crystal Bottom Lcd Screen Protector Film Guard For Nintendo For 3Ds
New Product Co., Ltd. , http://www.nbgameaccessories.com