我国在世界上是黄土最典型、分布面积较大的国家,约有44万平方公里(不包括经过扰动、改造的次生黄土状土)。这些黄土主要分布在西北、华北和东北南部,特别在黄河中游的陕北、晋西、陇东和宁南等地,连续分布,形成波浪起伏的黄土高原,犹如黄土的海洋。在这里黄土厚度一般达到数十米至数百米。洛河及泾河中下游厚度较大,可达百米以上,如陕北洛川塬厚达130—160米,陇东的董志塬黄土厚达200米,环县达285米,定边县姬塬厚达300米,成为我国黄土厚度的几个中心。我国黄土厚度之大,地层之全,是世界上其他国家所没有的。茫茫黄土海,千姿百态,各种各样的黄土地貌,组成了驰名世界的独特的黄土高原地貌景观。正确地认识黄土地貌,对改造黄土高原,治理水土流失,具有重要的现实意义。 China is the loess in the world with the most typical and large distribution area with an area of ​​about 440,000 square kilometers (excluding the disturbed and transformed secondary loess-like soil). The loess is mainly distributed in the northwest, north and northeast, especially in the middle reaches of the Yellow River in northern Shaanxi, western Shanxi, eastern and southern Ningxia and other places, continuous distribution, the formation of undulating loess plateau, like loess ocean. Here loess thickness generally reach tens of meters to hundreds of meters. Luohe and Jinghe River in the middle and lower reaches of the larger thickness, up to 100 meters, such as Luochuan Plateau in northern Shaanxi 130-160 meters thick, Longdong Dongzhiyuan Loess thickness of 200 meters, 285 kilometers Central County, Dingbian County Jiyuan Thickness of 300 meters, becoming China’s loess thickness of several centers. The great thickness of loess in China and its complete strata are not what other countries in the world have. The vast loess sea, in different poses and with different expressions, a variety of loess landscape, composed of the world famous unique landscape of the Loess Plateau. Correctly understanding the loess landform has important practical significance for rebuilding the Loess Plateau and controlling soil and water loss.