Objective The Lop Nor Basin is a very important Quaternary potash-formation basin in China. It is a typical sulphate- potash brine mine with an average grade of 1.4% （KC1） in underground concentrated brines. It is e...Objective The Lop Nor Basin is a very important Quaternary potash-formation basin in China. It is a typical sulphate- potash brine mine with an average grade of 1.4% （KC1） in underground concentrated brines. It is extraordinary that the reservoir of potassium-rich brines is glauberite stratum rather than halite rock. The anomalous potassium enrichment, advanced in relative early stage of lake evolution （sulphate stage）, has attracted much attention in the recent twenty years. Many researchers consider that there may be other source supply besides the Tarim River.展开更多
The Lop Nur dry salt lake,Xinjiang province,is charactered by typical physiognomy salt-crust,located in39.6-41.3N.latitude and 89.6-91.4E.longitude.The thickness of salt-crust is about from 20 cm to 100 cm,and
1 Introduction The Lop Nor playa,located in the eastern end of the Tarim Basin,capped with a thick salt crust covering an area of approximately 5,500 km2(Ma 2007)that closely resembles a"Great Ear"in satelli...1 Introduction The Lop Nor playa,located in the eastern end of the Tarim Basin,capped with a thick salt crust covering an area of approximately 5,500 km2(Ma 2007)that closely resembles a"Great Ear"in satellite images.Understanding the formation of the salt crust can provide important展开更多
High precision elevation measurements using DGPS were carried out along three representative tran- sects for the "Great Ear" area, a dry salt lake within the Lop Nor basin. Results indicate that the Lop Nor ...High precision elevation measurements using DGPS were carried out along three representative tran- sects for the "Great Ear" area, a dry salt lake within the Lop Nor basin. Results indicate that the Lop Nor basin is only 5.2 m deep and its lowest point occurs at the center of the "Great Ear". In addition, the basin is asymmetric - steeper in the southwest (0.19‰) and gentler in the northeast (0.09‰). Points along the same "Great Ear" ring were found to have an identical elevation value, but different when from different ones (lower towards the center). The spacing of the "Great Ear" rings was found to be closely related with the surface steepness. The closer the "Great Ear" rings are spaced, the steeper the ground surface, and vice versa. These findings support the argument that the "Great Ear" rings are the former shoreline trails left behind by Lop Nor water during the last few episodes of recession towards its total dry up. A comprehensive analysis of the high precision elevation data, historical accounts, aerial and satellite photographs and imagery, and official topographic maps of the study area suggests that the "Great Ear" area in the Lop Nor basin was incorrectly mapped as being covered by a great body of water on the 1963 topographic maps. A re-interpretation of the 1958 aerial photographs and newer remote sensing imagery indicated that the "Great Ear" ring structure was already in place in 1958 and it continued to appear on the subsequent remote sensing data without any major changes. It is estimated that lake water in the "Great Ear" area of the Lop Nor basin disappeared between the late 1930s and early 1940s.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.41002028)the Central Public-Interest Scientific Institution Basal Research Fund(Grant No.YK1404)Technology Foundation for Selected Overseas Chinese Scholar, Ministry of Personnel of China(Grant No.A1406)
文摘Objective The Lop Nor Basin is a very important Quaternary potash-formation basin in China. It is a typical sulphate- potash brine mine with an average grade of 1.4% （KC1） in underground concentrated brines. It is extraordinary that the reservoir of potassium-rich brines is glauberite stratum rather than halite rock. The anomalous potassium enrichment, advanced in relative early stage of lake evolution （sulphate stage）, has attracted much attention in the recent twenty years. Many researchers consider that there may be other source supply besides the Tarim River.
文摘The Lop Nur dry salt lake,Xinjiang province,is charactered by typical physiognomy salt-crust,located in39.6-41.3N.latitude and 89.6-91.4E.longitude.The thickness of salt-crust is about from 20 cm to 100 cm,and
基金supported by National Natural Science Foundation of China (Grant No. 41002028)Central Public-interest Scientific Institution Basal Research Fund (Grant No. K1102)
文摘1 Introduction The Lop Nor playa,located in the eastern end of the Tarim Basin,capped with a thick salt crust covering an area of approximately 5,500 km2(Ma 2007)that closely resembles a"Great Ear"in satellite images.Understanding the formation of the salt crust can provide important
基金the National Natural Science Foundation of China (Grant No. 40671080)the Program for Changjiang Scholars and Innovative Research Team in University (Grant No. IRT0412)the Key Subject of Soil Science Program in Xinjiang
文摘High precision elevation measurements using DGPS were carried out along three representative tran- sects for the "Great Ear" area, a dry salt lake within the Lop Nor basin. Results indicate that the Lop Nor basin is only 5.2 m deep and its lowest point occurs at the center of the "Great Ear". In addition, the basin is asymmetric - steeper in the southwest (0.19‰) and gentler in the northeast (0.09‰). Points along the same "Great Ear" ring were found to have an identical elevation value, but different when from different ones (lower towards the center). The spacing of the "Great Ear" rings was found to be closely related with the surface steepness. The closer the "Great Ear" rings are spaced, the steeper the ground surface, and vice versa. These findings support the argument that the "Great Ear" rings are the former shoreline trails left behind by Lop Nor water during the last few episodes of recession towards its total dry up. A comprehensive analysis of the high precision elevation data, historical accounts, aerial and satellite photographs and imagery, and official topographic maps of the study area suggests that the "Great Ear" area in the Lop Nor basin was incorrectly mapped as being covered by a great body of water on the 1963 topographic maps. A re-interpretation of the 1958 aerial photographs and newer remote sensing imagery indicated that the "Great Ear" ring structure was already in place in 1958 and it continued to appear on the subsequent remote sensing data without any major changes. It is estimated that lake water in the "Great Ear" area of the Lop Nor basin disappeared between the late 1930s and early 1940s.
