The mysterious Treasure in Big ears.

In the 1970s, a satellite photo published by the American academic magazine was shaped like the outline of a human ear, with earrings, earholes and earlobes, which is called "

The Sea of death.

The "big ear" Lop Nur.

Over the past hundred years, it has attracted generation after generation of scientists to risk their lives to come here for investigation and research.

So how did this "big ear" come into being? what's the mystery about it?

"big ears" satellite photos.

Lop Nur is located in the northeast of Tarim Basin and Ruoqiang County in Xinjiang, with east-west Altun Mountain and Kunlun Mountains in the south. Lop Nur is also known as Lop Nur, which means water-rich lake in Mongolian.

Tarim River on the southwestern margin of Lop Nur.

The Tarim River, the Peacock River, the Chechen River and the Shule River all converge here and are the key points of the ancient Silk Road in the eastern Tarim Basin.

It is low-lying and is the water gathering center of the Tarim Basin in southern Xinjiang.

The area once reached 200000 square kilometers.

From the endless salt crust, we can imagine how vast the Lop Nur water area used to be, so why did Lop Nur dry up now and become a "sea of death" that is barren and seldom visited?

1700 years ago, the ancient kingdom of Loulan mysteriously disappeared.

In 1900, Swedish geographer and explorer Sven Heding discovered the ruins of the ancient city.

The Loulan Beauty Creek Princess unearthed here has so far attracted the attention of the world.

The global drought is the background for the disappearance of Loulan.

With the uplift of the Qinghai-Tibet Plateau, it is difficult for the warm and humid air currents in the Pacific and Indian oceans to reach here, and the drought has gradually intensified. Coupled with the fact that human beings have destroyed the ecological balance of nature, water interception, excessive reclamation and so on, the whole lake has finally dried up.

The climate of Lop Nur area is hot, the highest temperature in summer is higher than 40 degrees, there is only more than 30 millimeters of precipitation every year, but the evaporation is as high as 3000 millimeters.

In the middle of last century, Lop Nur completely dried up and became a dry salt lake at Lop Nur.

The accumulation of boulders carried by strong winds.

After the Lop Nur dried up, almost all the plants on the edge of the lake basin and the old route of the Tarim River in the upper reaches of the Lop Nur died, the interior of the lake basin was covered by salt crust, and the rocks around the basin were exposed. In the harsh natural environment such as dry climate and large temperature difference between day and night, the rocks expand and shrink in heat and cold. Continue to produce physical weathering, broken into pieces of different sizes, and transported, sorted and re-broken under the action of strong weathering, and then accumulated in places where the wind slows down.

The wind in Lop Nur is strong all the year round, and the gale season is from June to August, which often causes sandstorms.

When the gale strikes, the moving sand ridges and dunes roll forward, the sand is flying all over the sky, and the sky is dark. The windy day of level 8 or above can last more than 2 months in Lop Nur, and the climate is extremely bad.

The disappearance and death of geologist Peng Jiamu and explorer Yu Chunshun made Lop Nur even more mysterious.

The harsh natural environment makes it difficult for people and animals to live, so Lop Nur has the name of "Sea of death".

Landform of Bailongya Mountain in Lop Nur.

The formation of big ears.

There are several theories about the cause of the Lop Nur ear print, but at present, a more mainstream view is that the big ear ear print is a kind of rhythm line of Lop Nur Lake water receding.

It shows that the dry salt lake in Lop Nur has experienced many times of lake water growth and decline, retreat and shoreline migration.

Generally speaking, the formation of salt is the continuous evaporation and concentration of water in the closed basin under the action of arid climate, and the salts gradually reach saturation and precipitate in solid phase.

After the withdrawal of the dry salt lake, the sediment at the bottom of the lake is exposed, and the strong surface salt precipitation process is still carried out due to the capillary evaporation of groundwater, resulting in the formation of salt shells of different shapes.

Scientists believe that the formation of "big ears" in Lop Nur is closely related to the type of surface salt crust, micro-geomorphology, cracking shape, material composition and zonal distribution of mineral composition in dry salt lake.

Desert Pearl-Lop Nur Potash Mine.

On the road from Ruoqiang to Lop Nur, you can see endless salt crusts, like the land that has just been turned over in spring.

This salt crust landform extends to tens of thousands of square kilometers.

In addition to the Gobi, desert, this is another unique landscape of Lop Nur.

An endless crust of salt.

The salt crust is distributed in a large area of hexagons, and the large hexagons are covered with small hexagons, and in a larger scale, the salt crust is extruded to form a giant salt ridge, which is like building a wall for the salt crust, which is very spectacular.

Why does the salt crust form this unique hexagonal structure?

Giant salt flower in Lop Nur salt pond.

Scientists have given the answer: in the early stage of lake recession, the groundwater level is relatively shallow, the freshly exposed salt layer is rich in saturated brine, salt minerals grow in the form of replacement and crystal embedding, and constantly fill sediment pores, and hexagons are the most stable in nature. the energy consumption is the lowest, and the underground brine rises continuously under the action of capillarity, crystallizing in the intercrystalline pores, resulting in an increase in volume, which in turn causes the surface to be lifted.

Finally, a roughly hexagonal shape is formed, and fissures are formed at the hexagonal boundary, and then the intercrystalline and underground brine rises preferentially along the cracks, causing the gradual increase of polygonal ridges, and the successive precipitation of fissure salts in the rising process, forming a longitudinal squeezing pressure stress, which promotes the polygonal ridge to further expand, expand and shrug, and gradually form a bowl-shaped or honeycomb-like salt crust landform.

The growing salt flower.

Potassium is one of the three indispensable elements of nitrogen, phosphorus and potassium for crop growth.

Potassium can strengthen the roots of plants and improve the quality of fruits.

If plants are deficient in potassium, they will get osteomalacia and even die.

China is a large agricultural country, there is a large shortage of potassium in arable land, while China's potash production can not meet domestic demand, 50% potash fertilizer needs to be imported.

The identified resources of soluble potash deposits in China are 1.005 billion tons of potassium chloride and 535.5 million tons of basic reserves, accounting for about 5 percent of the world's total potassium reserves, of which more than 89 percent are concentrated in the Qaidam Basin in Qinghai and the Lop Nur Salt Lake in Xinjiang. among them, the potash reserves of Lop Nur is about 250 million tons.

Researchers take samples at the bottom of Lake Lop Nur.

Potash production base in the hinterland of Lop Nur.

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The significance of the large potash resources discovered in Lop Nur is equivalent to the discovery of Daqing oil field. Why is this desert so rich in potash resources?

Since the Quaternary period (about 2 million years ago), due to the neotectonic movement, the Lop Nur has become the catchment center of the Tarim Basin, and the rich potash ore materials have been continuously transported to the Lop Nur, coupled with the extremely dry climate, forming a large potash deposit.

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Brine salt