How is the Loess Plateau formed and how high is it?

As we all know, there are four plateaus in China, the Qinghai-Tibet Plateau is the largest and the highest altitude, and the other three plateaus are Inner Mongolia Plateau, Yunnan-Guizhou Plateau and Loess Plateau. Speaking of the Loess Plateau, everyone will definitely think of the song "Loess High Slope" which was popular all over the country more than 3 years ago. The lyrics are slightly as follows: My family lives on the loess high slope, and strong winds have blown over it. ..... according to my cave drying my arm, and my cow followed me. ..... Leaving me singing as far as the eye can see, and the Yellow River around me. "Many people's impressions of the Loess Plateau actually come from this song.

the loess plateau is located at the junction of northwest China, due north China, Qinghai-Tibet Plateau and Qinling Mountains, involving Gansu (east), Qinghai, Ningxia, Shaanxi (north), Shanxi, Inner Mongolia, Hebei and other provinces. The Loess Plateau is located in the east of Lanzhou section of the Yellow River, south of Mu Us Sandy Land, north of Guanzhong Basin and west of Taihang Mountain, with an area of about 64, square kilometers, which is slightly smaller than that of France (including French Guiana in South America) with an area of 67, square kilometers.

It is estimated that even children know the origin of the name of the Loess Plateau, because there are so many loess. In this world, no region has such a large area of loess as the Loess Plateau. Where did all this loess come from? A lot of loess was formed in the Quaternary period more than two million years ago, which is academically called aeolian deposits. These loess are also divided into two types, one is primary loess and the other is secondary loess. The so-called primary loess is equivalent to old residents, and the so-called secondary loess is equivalent to new residents.

There is also a saying that the Loess Plateau was an oversized lake about 8 million years ago. At that time, the earth was raging, blowing a lot of loess and dust into this lake. Over time, the loess filled the lake, and the altitude became higher and higher, eventually forming the present Loess Plateau.

The Loess Plateau is not a flat plateau, and it is appropriate to describe the topography of the Loess Plateau with "thousands of valleys and valleys". You must have seen many literary works reflecting the historical features of northern Shaanxi. One of the most classic images is an old man with a white towel, riding a donkey and singing "Journey to Heaven", walking through the ravines.

The loess plateau is not very hard because of its soil quality, which is different from that of Qinghai-Tibet Plateau and Yunnan-Guizhou Plateau. Due to the rain erosion and the impact of the Yellow River for millions of years, the soil in the Loess Plateau has been eroded by various reasons, forming tablelands, beams, promontories and ditches. People sometimes listen to folk songs in northern Shaanxi and often hear these nouns. For example, "Who's that?", the lyrics slightly say: "Who's that on the Geliangliang of the dam? That's my second sister. ..... I'm standing on this beam. Where are you, sister? "

what is a plateau? To put it simply, the top of a mountain is not sharp, but a plain area where you can cultivate. Some tablelands are very close, so two people can clearly hear each other's conversation when standing on their own gardens. But if you want to shake hands, I'm sorry, it will take you a long time to say the least. What is Mao? In this way, if the tableland is the Australian mainland, then the promontory is the Greenland subcontinent, which is much smaller than the tableland, but its structure is similar to that of the tableland. The loess promontory is mainly concentrated in the northern part of the central loess plateau, that is, it starts from Luliang Mountain in Shanxi in the east, Liupanshan Mountain in Ningxia in the west, and the Ziwuling Mountain between Shaanxi and Gansu in the south, especially in Yan 'an.

how high is the loess plateau? Generally speaking, it is high in the west and low in the east. The highest part of the Loess Plateau is in the west, and the western part of the famous Liupanshan Mountain is about 3 meters above sea level, that is, Lanzhou, Gansu, Dingxi, Gansu and Haiyuan, Ningxia. The farther east the Loess Plateau goes, the lower the altitude is, for example, from Liupanshan in the west to Luliang Mountain on the east bank of the Yellow River in the east. The highest altitude in this area is about 2 meters. In the area east of Luliang Mountain, the Loess Plateau is not so high, generally about 1 meters. There are many river valleys in the eastern part of the Loess Plateau, such as the famous Fenhe Valley, which starts from Taiyuan in the north and reaches Hejin in the south, which invisibly lowers the "overall height" of the Loess Plateau.

Many people's first impression of the Loess Plateau is "soil". This may have been the case in the past, but in the past few decades, with people's efforts, the vegetation coverage rate has been increasing, and now the Loess Plateau is not so "earthy".

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