Lop Desert

Because of geography and climate, the boundless desert was formed in Xinjiang, China. After the Silk Road had been formed, the trade caravan passed through it difficultly and many people died in this desert and many legends had been eulogized. So this area was covered with the mysterious veil.

“There are no flying birds, and the white bones are seen anywhere”. On the abominable condition, the tribes are moving on the Gobi and fighting for the resource continuously. The sand covered lots of ancient cities. The geographer, rocksys and archaeologists in various countries admired and coveted the ancient and mysterious cultural relics, and they investigated and explored it. During one hundred years, they raised the tendency of researching and exploring it.

Nowadays, in the south of continuous Tianshan Mountains, and the east of Taklimakan Desert in Tarim Basin, there was a drying lake billabong and it was Lop Nur. People customarily regarded Lop Nur and surrounding area as Lop Nur billabong. Its generalized area was Beishan Mountains as its east boundary, connecting with Taklimakan Desert west, Arjin Mountains and Kuruktag Mountains respectively as its southern and northern boundaries. This area was in the east longitude 88°to 92°and north latitude 39°30’ to 39°41’ and its acreage was nearly one hundred thousand s.q.km.

In this wide area, its landform included three parts: plain in front of the mountain, alluvion-lake plain, and lake plain. On the earth's surface, the natural landscape included conglomerate Gobi, desert, salt desert, and wind-erosion survival massif. The proportion of alluvion plain and plowland on the oasis was little. The southern hypsography was higher than the north and the east and the west were higher than the drying river and the lakebed billabong.

The billabong of Lop Nur was located in the hinterland of European-Asian continent, which was in the east end of relatively close Tarim Basin. The weather was very arid and the annual average rainfall was 17-20mm only, but the evaporation was more than 3,000 mm. The windy season was from February to June each year and the wind direction was mainly the northeaster. There was a gale every 3-5 days. The summer was broiling and the air temperature was from 40-50℃. The winter was fine and dry, and there was no snow covered with ground.

The scientists researched and thought that the dry, hot, rainless and windy weather had formed for a long time. It had formed at the end of Tertiary and at the beginning of the Quaternary Period. The scientists analyzed the gesso sediment, salt sediment and the ancient plants in the Quaternary Period and made a conclusion, the environment had changed for twenty thousand and the dry climate had not changed, and it was still the desert climate. Because of human’s economic activities development of agriculture and population, the dry natural environment had exacerbated and the desert had formed.

Because the glide moved them and the wind eroded them, the gravel on the earth’s surface was thick. Because of the continuous erosion of the wind, there were many 20-40 meters massif, rock and earth pillar in this area.

As the unattached geographical unit, the conformation of Lop Nur billabong was the same as the Tarim Basin and it had been changed at the end of Trias in Mesozoic hundreds of millions of years. Lop Nur showed the status of countermovement compared with the surrounding area and it formed the comparison landform. So there were two opposite physiognomies: wide billabong and hilly country with high surrounding area. Lop Nur had been the center of collecting water in Tarim Basin. The lowest point of the billabong was 780 meters above sea level and it was the lowest area in Tarim Basin.

There were landforms with many massifs and dongas in the east, north and west of the billabong. It was the “Yadan” landform we often mentioned.

The word “Yadan” was transliterated from the ancient Uygur word “Yar”, meant “cliff”. Since the end of 19th century, some researchers had used the word “Yadan” to describe the landform with many massifs and dongas, and this had been gradually accepted by the academe. It continued to be used until now.

The record of this landform was recorded in Shui Jing Zhu (Commentary on the Waterways Classic) written by Li Daoyuan in the period of Northern Wei Dynasty. The author described the “Long City” as that the wind eroded it into the figure of dragon and it faces the southwest. So its name is Long City.” He thought that the natural landform had been formed in the influence of water and wind.

The landform of “Yadan” in Lop Nur was divided into four parts, including one in the lower reaches of Konqi River, another in Bailongdui, the third in Sanlongsha and the forth in 阿奇克 Valley.

The landform “Yadan” in the lower reaches of Konqi River mainly included Long City and Kroraina. Its range was nearly 40 kilometers from the east to the west and 160 kilometers from the south to the north. Its acreage was 6,400 s.q.km. In this area, the landform “Yadan” was made up of earth, sand and rock. The height of the massifs and dongas was from 20 meters to 25 meters and the length was from 30 meters to 50 meters.

In 1930’s, Chinese old scientist Chen Zongqi investigated Lop Nur. He called the large difference of the landform height “Maisai” and called the small difference of the landform height “Yadan”. He thought the former was in early age and the latter was in late age.

The landform “Yadan” of Bailongdui was in the northeast of Lop Nur. Its width was 20 kilometers from the east to the west and its length was about 80 kilometers from the south to the north. The acreage was 1,600 s.q.km. In this area, the length of the massifs was from over 200 meters to 500 meters and the massifs were made up of the offwhite earth and sand. It looked like some large dragons paddling in the lake. Standing on the bank, your ears were reverberated with the wind.

阿奇克 Valley and Sanlongsha were located in the east of Lop Nur and people got used to call it lower reaches valley of Shule River. It was connected with Dunhuang east. In here, the landform “Yadan” area is not large. The plain sandlot and Gobi was the main landform in this area. This area was called “Moheyanqi” in Chinese ancient materials and Xuan Zang wrote in the Tales of the Triple-Text Master in Great Loving-Kindness Temple, that the length of Moheyanqi is over 800 li. Its name was Shahe in ancient time. There are no flying birds and beasts and float grass. At night, there are many monsters and mysterious fire. The wind sweeps the stones, like the heavy rain.

Because of the conformation movement of Quaternary Period, Lop Nur became the terminal of all rivers in Tarim Basin and the center of collecting the salt. So this brought up the special shell and the rule of collecting the salt.

Seeing from the picture sent by American satellite, there were many circle-shaped figure around Lop Nur and they liked human’s ears. The geologists called them “circle line” or “helix line”.

What on earth was the so-called “helix line”? Someone thought it was the bank of Lop Nur. During 1980 to 1981, Xinjiang Branch of Chinese Academy of Sciences set up a integrate investigation team to enter Lop Nur three times and investigated Lop Nur and made a new analysis report of the character of helix line.

The scientists thought that the lake water in various periods spent different time to dry up, so the shell of various form, ingredient and color formed in the process of collecting salt. The washy circle line was the thick ramous shell and the dark circle line was the thin ramous shell.

In history, Lop Nur was a low and wet salt marsh. In ancient Chinese historical records, Lop Nur had other names such as Puchang Sea, Yanze and Aoze. In Tales of Western Regions, the Han Dynasty,

Puchang Sea, another name is Yanze. It is over 300 li away from Yumen Pass and Yang Pass. Its range is 300 li. The water doesn’t change, so we think it prowls under the ground and gets out of Jishi. It is called Chinese river.

The River Water, Shui Jing Zhu described, “the salt is hard and the passengers dig up the ground and find the large salt bed”.

After Lop Nur became the center of collecting water in Tarim Basin, Tarim River, Konqi River, Qarqan River, Washixia River, Ruoqiang River, and Milan River entered the Lop Nur. And the Shule River in the east had entered Lop Nur. The area that these rivers passed through continuously dissolved soil and efflorescent salt, and then moved them into the billabong. Except water gathering on the surface, the underground water also gathered here. The long-tem evaporation and inspissation was the reason that the hard salt shell formed in Lop Nur.

In fact, Lop Nur had go through the process of collecting water and drying up since the lake formed. At first, the range of Lop Nur was large and it had gradually reduced until it dried up. The various kinds of salt shells formed in the various stages of Lop Nur’s evolvement. Seeing from the various salt shells—circle lines that were the mark of evolvement, Lop Nur backed from the east to the west. There was no track of movement. What was the so-called moving lake?

Translated by Beijing Star-light Translation Center
Compiled by Historical Department of www.travel-silkroad.com
December 31st, 2000