Development and Utilization of Potash Resources in Lop Nor,Xinjiang

The Lop Nor saline lake in the east Tarim basin,extends115 km from the south to the north,and 90 km from the east to the west,which covers an area of 10350 km2.It is the world’s largest dry saline lake,and is also so far the largest

Geochemical Characteristics of the Fluid Inclusions Trapped in Primary Gypsum of the Lop Nor Basin

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.

An Attempt to Date the Salt-mounds in the Lop Nor Playa

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

A study on historical location and evolution of Lop Nor in China with maps and DEM

Lop Sea,located at the east end of the Tarim Basin,Northwest China,dried up permanently,which is the terminal lake of the Tarim River.Lop Sea was considered as the lake basin of Lop Nor since Quaternary.However,the possibility that Lop Nor was away from the Lop Sea in historical time is crucial to be discussed to interpret the proxy records in sediment profiles.To obtain a general view of the evolution of Lop Nor and Lop Sea in a historical period,several approaches were adopted in this paper.First,the Qianlong Thirteen-Row Atlas,an ancient imperial atlas of the Qing Dynasty,which was completed around 1760,indicated that the Tarim River formed a relatively large lake at its modern upstream region.Second,a Digital Elevation Model(DEM)with a 10-m spatial resolution and a relative precision of 0.42 m was derived from TanDEM-X/Terra SAR-X satellite image pairs using the interferometry method,which was verified using ICESat-GLAS laser footprints and a local DEM acquired by a drone.Finally,based on the spatial analysis of historical documents,expedition reports,sediment profiles and archaeological evidence,it can be deduced that the lacustrine deposition was discontinued in the Lop Sea.Six episodes in the evolutionary history of the drainage system in eastern Tarim Basin were summarized.The proved depositional condition variations could be used for future interpretation of proxy records in sediment.The high-accurate DEM provided a reference for the location of further fieldwork in the Lop Sea.The method proposed in this paper may be efficient for the research of inland lakes or rivers in global arid regions.

Evolution of Quaternary Depositional Environments in Lop Nor,Xinjiang:Sedimentary Records from LDK01 Drilling

Lop Nur is located in the interior of Asian and the lowest part in the eastern Tarim Basin.It is the final destination of major river systems in Tarim Basin and the accumulation center of salt materials(Xia,1987).As

Hydrochemical Characteristics and Evolution of Underground Brine in Lop Nur,Northwestern China

Lop Nur is located at the eastmost end of the Tarim Basin in Xinjiang,Northwestern China.This study reviews the hydrochemical characteristics and evolution of underground brine in Lop Nur,based on analytical data from 429 water samples(mainly brine).It is found that in the NE-SW direction,from the periphery to the Luobei sub-depression,while the hydrochemical type varies from the sodium sulfate subtype(S)to the magnesium sulfate subtype(M),the corresponding brine in the phase diagram transfers from the thenardite phase(Then)area,through the bloedite phase(Blo),epsomite phase(Eps),picromerite phase(Picro),finally reaching the sylvite phase(Syl)area.As for the degree of evolution,the sequence is the periphery<Luobei horizontally and the overlying glauberite brine<the underlying clastic brine vertically.It is concluded that the oxygen and hydrogen isotopic compositions of the brine have evidently been affected through the effects of evaporation and altitude,as well as the changes in local water circulation in recent years.Boron and chloride isotopic compositions show that the glauberite brine is formed under more arid conditions than the clastic one.The strontium isotopic composition indicates that the Lop Nur brine primarily originates from surface water;however,deep recharge may also be involved in the evolution of the brine,according to previous noble gas studies.It is confirmed that the brine in Lop Nur has become enriched with potassium prior to halite precipitation over the full course of the salt lake's evolution.Based on chemical compositions of brine from drillhole LDK01 and previous lithological studies,the evolution of the salt lake can be divided into three stages and it is inferred that the brine in Lop Nur may have undergone at least two significant concentration-dilution periods.

A preliminary study of chronology for a newly-discovered ancient city and five archaeological sites in Lop Nor, China

In the past century, it has long been debated in the archeological, historical, geographical, and many other related communities where the capital of the Luolan and Shanshan states was in the Lop Nor region. This paper presents three AMS radiocarbon ages from a newly-discovered ancient city at about 6.3 km to the northwest of the Xiaohe Graveyard, and fifteen new radiocarbon ages from the Loulan (LA), LE, Qieerqiduke, Milan, and Tuyin sites in Lop Nor. The new investigation shows that the age of newly-discovered ancient city is at ca. 440–500 AD, belonging to the Northern Wei Dynasty (386–534 AD). This is about 100–300 years younger than Loulan (ca. 100–230 AD), LE (ca. 230–300 AD), Qieerqiduke (ca. 200 AD), and Tuyin (ca. 100 AD). A wooden beam from Milan fortress is dated to ca. 370 AD, while the age on north wall at west gate of the fortress is younger, around 770 AD, suggesting that its construction time might be at the Tang Dynasty. According to 14C ages, cultural relic style, and the geographical location, the newly-discovered ancient city is probably attributed to "Zhubin City", as documented in the historical literature. Temporally, we name the city "ancient Zhubin River City". However, the characteristics and functions of this ancient city are largely unknown and need more detailed archaeological excavation and investigation in the future. Given its location near the ancient postal relay of Alagan on the crossroad, there is no doubt that the newly-discovered city was at an important geographical position on the Silk Road, no matter whether it was called "Zhubin City", or "Lielo City", or the capital of Loulan state–"Yuni City". Our findings provide new evidence for the temporal and spatial distribution of ancient relic sites and the development of civilization in western China, thus contributing to our understanding of the relationship between human activities and environmental change in the Lop Nor region.

High precision topographic data on Lop Nor basin's Lake "Great Ear" ? and the timing of its becoming a dry salt lake

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.

PRELIMINARY STUDY ON SEDIMENTARY ENVIRONMENT OF THE LOP NOR SALT LAKE AND ITS PROSPECT FOR POTASSIUM

In October, 1989, the two-route surveying (Fig. 1) was completed by the Saline

The paleoclimatic environment reconstruction of Lop Nur in NW China in UAV spectroscopy

The change in the ecological environment in the arid core area is a critical issue in the context of global warming.To study the paleoclimate evolution,precise identification of minerals deposited in Asia’s arid hinterland,Lop Nur Salt Lake,NW China was conducted.The hyperspectral data of the salt crust was sampled to identify the species and content of sedimentary minerals,and the multispectral photos were used to reconstruct the salt crust morphology using the unmanned aerial vehicles platform.The SUnSAL(sparse unmixing by variable splitting and augmented Lagrangian)method was employed to inverse the sedimentary mineral components along the shoreline.The heterogeneity of salt and clay minerals in bright and dark ear-shaped strips was evaluated.The paleoclimatic environment associated with salt lake extinction was reconstructed by analyzing paleoclimate records of sediments,spectral reflectance and morphology of the salt crust.Results show that:(1)the variations in the micro-geomorphology of the salt crust are obviously the reason for the formation of bright and dark ear-shaped strips and the differences in the species and relative content of the sedimentary minerals are the microscopic reason.The high ratio of sedimentary salt minerals to clay minerals(RS/C)contributes to the high reflectivity,and the salt crust presents a bright texture.The low RS/C results in the low reflectivity,salt crust presents a dark texture;(2)the bright and dark ear-shaped strips represent warm-arid and cold-humid climates.The shape of the Lop Nur Lake shoreline evolved due to alternating warm-dry and cold-humid paleoclimate changes.

基于LOP模型的事故隐患分类分级研究

为构建科学有效的事故隐患(AP)排查治理长效机制,基于防护层(LOP)模型,建立统一的、便于执行和管理的事故隐患分类分级框架。讨论分析事故隐患及危险源的几种定义,将事故隐患分为设计建造、基本过程控制、超限报警、安全控制、主动防护、被动防护和应急等新7大类,并定为严重、中等、一般等新3级。提出设置事故隐患排查治理指标,建立事故隐患分类分级标准备案机制。结果表明,事故隐患是事故的必要但不充分条件,是LOP安全防护功能下降或失效的充要条件,所建立的事故隐患分类分级框架是促进事故隐患排查治理工作的基础。

罗布泊地区1957—2017年气温的时空变化特征

以罗布泊地区1957—2017年日气温数据为基础,通过线性倾向估计法、移动平均法、距平与累积距平法、独立样本t检验法及IDW空间插值法,分析了近60 a罗布泊地区气温的时空变化及突变性特征.结果表明:罗布泊地区气温呈上升趋势,且平均线性增长率为0.27℃/10 a;年平均气温年际空间变化较显著,高值区集中分布于吐鲁番盆地区域,低值区集中分布于阿尔金山地区;季平均气温年际时空特征变化差异性强,冬季升温现象最显著,呈冬暖夏凉的变化趋势.进入21世纪后,气温处于高位震荡期,年平均气温及季平均气温时空特征变化显著且差异性增大,整体上呈增温趋势;罗布泊地区年平均气温累积距平曲线呈先下降后上升趋势,且突变年份集中在1987,1989,1996以及1997年.

罗布泊沉积物多相态Mg同位素的分离提取及其古气候指示意义

晚中新世地球气候格局和生态系统转换的原因是学界长期关注并富有争议的科学问题。近期发现中高纬度海表温度在7~5.4 Ma期间发生了一次剧烈降温事件,支持大气CO_(2)下降驱动假说,但一直缺乏同时期陆地明显降温的证据。Mg是主要的造岩元素之一,在表生地质过程中会发生显著的同位素分馏,是古气候领域的新兴代用指标。本研究选取塔里木盆地的罗布泊深钻岩心,进行了不同深度沉积物的多相态Mg同位素(δ^(26)Mg)的淋滤提取,并与Rb/Sr、CIA等传统化学风化指标进行对比,探讨其古气候指示意义。结果显示,沉积物岩心中碳酸盐相、硅酸盐相和全岩样品之间存在显著的δ^(26)Mg组成差异,其平均值分别为(−2.37±0.47)‰、(−0.20±0.33)‰和(−0.80±0.24)‰(2SD,n=7)。沉积物碳酸盐相的δ^(26)Mg在化学淋滤提取过程中易受硅酸盐相污染,且难以区分湖泊自生碳酸盐和外来碎屑碳酸盐,记录的环境气候信号较为复杂。相反,分离提取实验结果表明,不同深度、不同岩性的罗布泊沉积岩心样品淋滤后的残余相基本由硅酸盐相组成,与Rb/Sr、CIA等传统化学风化指标相比,其δ^(26)Mg组成与晚中新世以来海表温度等其他气候记录有更好的一致性。研究结果表明,罗布泊沉积物硅酸盐相δ^(26)Mg可以指示其物源区化学风化强度的变化。因此,通过测定气候敏感区湖泊沉积物中硅酸盐相δ^(26)Mg记录,可以为探讨中国西部晚中新世以来的气候变化机制提供新的制约。

消化性溃疡患者血SOD、NO及LOP水平变化研究

目的:探讨消化性溃疡患者血SOD、NO及LOP水平变化的变化规律,为消化性溃疡的治疗和诊断提供依据。方法:选取2006年12月～2009年1月于本院进行治疗的125例消化性溃疡患者为研究对象,将其设为观察组,同时选取同期的100例健康人为对照组,并对对照组及观察组治疗前后的血SOD、NO及LOP水平进行检测研究,并加以研究统计。结果:经研究比较发现,对照组与观察组治疗前SOD、NO及LOP水平比较,P<0.05,差异有统计学意义;观察组治疗前与治疗后4周差异较大,P<0.05,差异有统计学意义;观察组治疗前与治疗后8周差异较小,P>0.05。结论:消化性溃疡患者的血SOD、NO及LOP水平变化对于患者的诊断及治疗有着积极的意义,值得临床进一步研究及探讨。

基于LOP的分布式数据存储与查询技术

当今已经进入了云计算时代,其中,数据的分布式存储和查询也已成为大数据管理的关键技术之一.分布式数据管理在数据存储层面需要进行数据的分片和配置,在查询方面需要进行各节点查询子结果的配置与整合.对于结构化数据例如关系型数据已经具有了成熟有效的相关技术,但对于主要是半结构化、无结构化以及多种数据模式混杂的大数据而言,其分布式数据分片和配置还是一个具有需要深入研究的课题.本文针对具有广泛应用的具有时间标签的非结构化数据,提出了一种按照时间标签进行分片与配置的分布式存储与处理方案,相应的仿真实验表明本文的工作是可行的和有效的.

Features and Formation Mechanism of Faults and Potash-forming Effect in the Lop Nur Salt Lake,Xinjiang,China

The Lop Nur Salt Lake, located in the eastern part of the Tarim Basin, Xinjiang, China, has become a playa in the Quaternary. Rhombic in shape, the Lop Nur depression is mainly controlled by the NE-striking and nearly N-S-striking sets of faults. Since 1995, a superlarge brine potash deposit with potash resources of 2.50×10^8s t has been found in the Luobei subbasin in the northeastern part of the Lop Nur. We intensively studied the features and formation mechanism of faults inside the Lop Nur through satellite images, geomorphologic survey and continuous conductivity imaging and found seven subparallel graben faults formed under the action of nearly N 10° E principal compressional stress during deposition of the Lop Nur Salt Lake. These faults are up to 〉60 km long and 1-4 km wide and may extend downward for 1000 m or more. It is just under the action of these tensional faults that potash subbasius formed. The largest subbasin is the Luobei subbasin and the smaller ones are the Luoxi hollow, Erbei hollow and Tienan hollow. Investigation also indicates that the graben faults in the Lop Nur not only control the origin of the potash subbasins, but they themselves are also good brine reservoir structures, in which abundant potash-rich brines are stored. Therefore, The faults had played an important role in the potash formation of the Lop Nur.

The Impact of the Linked Factors of Provenance,Tectonics and Climate on Potash Formation:An Example from the Potash Deposits of Lop Nur Depression in Tarim Basin,Xinjiang,Western China

Potash deposits commonly accumulate in highly restricted settings at the final stage of brine evaporation. This does not mean that potash deposits are formed simply as a result of the evaporation concentration of seawater or lake water, but rather as a coupling result of particular provenance, tectonics and climate activities. In this paper, we focus on the formative mechanism of the potash deposits of Lop Nur depression in Tarim Basin to interpret the detailed coupling mechanism among provenance, tectonics and climate. In terms of the provenance of Lop Nur Lake, the water of the Tarim River which displays ＂potassium-rich＂ characteristics play an important role. In addition, the Pliocene and Lower-Middle Pleistocene clastic beds surrounding Lop Nur Lake host a certain amount of soluble potassium and thus serves as ＂source beds＂ for potash formation. During the late Pliocene, the Lop Nur region has declined and evolved into a great lake from the previous piedmont and diluvial fan area. Since the mid Pleistocene, the great-united Lop Nur Lake has been separated and has generated a chain system consisting of Taitema Lake, Big Ear Lake and Luobei Lake which has turned into the deepest sag in Lop Nur Lake. Dry climate in Lop Nur region has increased since the Pliocene, and became extreme at the late Pleistocene. The study implies that potash formation in Lop Nur Lake depends on the optimal combination of extreme components of provenance, tectonics and climate during a shorter-term period. The optimal patterns of three factors are generally characterized by the long-term accumulation and preliminary enrichment of potassium, the occurrence of the deepest sub-depression and the appearance of an extremely arid climate in Lop Nur region. These factors have been interacting synergistically since the forming of the saline lake and in the later stages strong ＂vapor extraction＂ caused by extremely arid climate is needed to trigger large scale mineralization of potash deposits.

Minerogenic Theory of the Superlarge Lop Nur Potash Deposit, Xinjiang, China

Located in the eastern part of the Tarim basin, Xinjiang, the Lop Nur was an ultimate water catchment area of the Tarim basin during the Quaternary. Through nearly ten years of investigation and research, the authors have found a superlarge brine potash deposit in the Luobei subbasin—a secondary basin of the Lop Nur depression. The deposit has been mined now. On that basis, the authors propose new theories on the genesis of the potash rock deposit. In the tectonic and geomorphologic contexts, the Tarim basin lies in a 'high mountain-deep basin' environment. At the beginning of the Quaternary, influenced by the neotectonic movement, the Lop Nur evolved into a 'deep basin' in the Tarim basin. At the end of the middle Pleistocene, neotectonic migration began to take place in the interior of the Lop Nur and a new secondary deep basin—the Luobei subbasin—formed gradually. Despite its small area, it is actually the deepest subbasin in the Lop Nur depression, where brines of the Lop Nur Salt Lake gather and evaporate, thus providing materials for the formation of a superlarge brine potash rock deposit. With respect to the phenomenon of brine concentration and change with deepening of the lake, the authors propose a model of 'high mountain-deep basin' tectonic migration for potash concentration. In the sedimentological context, the honeycomb-shaped voids developed in glauberite rock in the subbasin are good space for potash-rich brine accumulation. Study indicates that the deposition of glauberite requires recharge of calcium-rich water. In the Tarim area the calcium-rich water might come from deep formation water or oilfield water, and the river water recharging the Lop Nur Salt Lake was rich in sulfate radicals and other components; in addition, the climate in the area was very dry and the brine evaporated steadily, thus resulting in deposition of substantial amount of glauberite, potash accumulation in intercrystal brine and final formation of the potash deposit. Generally, potash formation in a salt lake undergoes a three-stage process of 'carbonates—?sulfates (gypsum and glauberite)—^chlorides (halite etc.)', but in the study area there only occurred a two-stage process of 'carbonates—>sulfates (gypsum and glauberite)'. The authors call this new geological phenomenon the 'two-stage potash formation' model. In conclusion, the superlarge Lop Nur potash deposit is the result of combined 'high mountain-deep basin' tectonism and 'two-stage potash formation'.

Holocene Yellow Silt Layers and the Paleoclimate Event of 8200 a B.P.in Lop Nur,Xinjiang,NW China

Many yellow silt layers have been identified in the Holocene sediments in the last lake of Lop Nur (playa), Xinjiang, northwestern China. Statistics of drill-hole cores have revealed more than one hundred layers, which exhibit regularity in time sequence. Study has further verified that these yellow silt layers were deposited through eolian processes. The time-frequency distribution diagram shows an obvious peak occurring at about 8200 a B.P., which is consistent with the dry, windy and cold climate event occurring at 8200 a in other places around the world. Therefore, this event is regarded as a response to the global climate change.