岩溶洞穴叠层石

岩溶洞穴叠层石系藻类等生物在洞穴弱光带富含钙质的岩溶水中，通过粘结捕获或同化作用沉淀碳酸盐面形成。油穴叠层石均显示双层叠置构造，即背光浅色层和向光深色层，并由细密纹层组成，。向光深色层疏松多孔，表面粗糙可见生物体；背光浅色层致密，表面光滑。因生长微环境的变化，其形态可分为３类：倾斜型，直立型和坝型。

CAVE STROMATOLITES IN KARST AREA

Here discussed are the distribution features, types and formation of the cave stromatolites in karst area near the cave entrance (in weak light condition), formed by algae and other microbes. The calcite carbonates were deposited through microbial binding and trapping or assimulation in cave water. These cave stromatolites are characterized by a doublelayered structure. The light--backed light color layer is tight with smooth surface. The light--oriented dark color layer is relatively loose and porous with rough surface and many colonized microbes. Both light and dark color layers were composed of numerous laminations. According to the different micro--environments in which they developed, the cave stromatilites could be divided into the incline type, the erect type and the dam type.