黄土高原地区黄土洞穴的成因研究

通过野外调查统计手段对黄土高原黄土洞穴的成因进行了研究。结果表明：黄土洞穴形成的控制因素主要包括地层厚度、土性、构造、地形地貌以及水文地质和气候条件等，其中黄土地层的土性、厚度及其空间组合形式和形态构成了形成黄土洞穴的物质基础。不同深度的黄土洞穴，其形成的主控因素不同，表层黄土洞穴多为生物成因，浅层黄土洞穴主要与黄土地层抗水蚀能力的垂直分异以及浅层的各种节理裂隙有关，中层黄土洞穴主要与节理裂隙有关。深层及极深层黄土洞穴与构造节理直接相关。

A Study on Origin of Loess Caves in Loessal Plateau

On the basis of the field survey and statistic, the causes of loess caves in the loessal plateau are studied in this paper. Result shows that the controlling causes of loess caves include the thickness of the loess layer, loess quality, structure, land form, hydrology, geology and climatic conditions, of which the loess quality, thickness of the loessal layer as well as their combinations formed the bases of loess caves. Loess caves of different depths have different main causes. The cause of superficial loess caves is related to biologic activities, of shallow layer caves to their differentiation of the anti-water erosion ability as well as the fissures inside, of middle layer caves to the fissures inside, and of deep and extra deep layer caves to the tectonic joint.