Magnetostratigraphy and ^(230)Th dating of a drill core from the southeastern Qaidam Basin:Salt lake evolution and tectonic implications

The Qarhan Salt Lake area is the Quaternary depocenter of the Qaidam Basin, and carries thick lacustrine sediments, as well as rich potassium and magnesium salt deposits. The abundant resources and thick sediments in this lake provide an ideal place for the study of biogas formation and preservation, salt lake evolution, and the uplift of the Tibetan Plateau. In this study, we attempt to construct a paleomagnetic and ^(230)Th age model and to obtain information on tectonic activity and salt lake evolution through detailed studies on a 1300-m-long drill core(15DZK01) from the northwestern margin of the Qarhan Salt Lake area(Dongling Lake). Based on gypsum ^(230)Th dating, the age of the uppermost clastic deposit was calculated to be around 0.052 Ma. The polarity sequence consist of 13 pairs of normal and reversed zones,which can be correlated with subchrons C2r.1r-C1n of the geomagnetic polarity timescale(GPTS 2012)(from ~2.070 Ma to ~0.052 Ma). Sedimentary characteristics indicate that Dongling Lake witnessed freshwater environment between ~ 2.070 Ma and 1.546 Ma. During this period, the sedimentary record reflects primarily lakeshore, shallow-water and swamp environments, representing favourable conditions for the formation of hydrocarbon source rocks. Between 1.546 Ma and ~ 0.052 Ma, the Dongling Lake was in sulphate deposition stage, which contrasts with the central Qarhan Salt Lake area, where this stage did not occur in the meantime. During this stage, Dongling Lake was in a shallow saltwater lake environment, but several periods of reduced salinity occurred during this stage. During the late Pleistocene at ~0.052 Ma, the Dongling Lake experienced uplift due to tectonic activity, and saltwater migrated through the Sanhu Fault to the central Qarhan Salt Lake area, resulting in the absence of halite deposition stage. The residual saline water was concentrated into magnesium-rich brine due to the lack of freshwater, and few potassium salt deposits occur in the Dongling Lake area.

Geological characteristics and genesis of subbottom pinnoite deposit of Da Qaidam salt lake in Qaidam Basin

Da Qaidam salt lake is known for its both liquid and solid boron resource.Data from previous investigation of the Da Qaidam salt lake provided a comparable framework for this study that focused on investigating the section beneath the bottom of the perennial salt lake,including the timing,

Salt Lake in Chaidamu Basin

Chaidamu Basin(柴达木盆地) is in the west of China. It covers an area(地区) of 220,000 square kilometres(平方公里). The number of salt lakes(盐湖) is more than twenty in it. Chaerhan(察尔汗) Salt Lake is the largest in this area. If you get here, you will find that in the lake there is no water but a thick layer(层) of salt. You can walk in it without difficulty, and cars can come and go across it. The thickest layer of salt in this basin is about fifty metres thick. People tried their best to use the salt to build house...

Grain-size characteristics of linear dunes on the northern margin of Qarhan Salt Lake, northwestern China

In order to clarify the formation mechanism of linear dunes on the northern margin of Qarhan Salt Lake, northwestern China, we analyzed the grain-size and sorting parameters of the dune and interdune sands. The surface sands （0-30 ram） from the dune base to the crest of both flanks and interdune corridors were sampled along transects from upwind to downwind through the dune field. The results indicated that the grain-size distribution differed at different positions between and within the dunes. The frequency curve for dune sands mainly showed a bimodal distribution, while the interdune sediments showed a trimodal distribution. The grain size distribution of the linear dunes showed a finer crest pattern, i.e. the crests were composed of sands that were generally finer, better sorted than those of base sands. In addition, at the dune field scale, the dune crest sands were tending to become much finer but sorting became worse along the downwind transects. However, the grain-size parameters of sediments in the interdune corridors showed no clear pattern. The results demonstrated that the grain size and sorting parameters exhibited a systematic change not only at the individual scale but also at the dune field scale. Our results quantitatively estimate the limited role of cohesive sediments on the formation of linear dune under unidirectional wind regime. More attention should be paid to a long-term wind regime observation, internal sedimentary structures and their formation ages.

Pattern analysis of a linear dune field on the northern margin of Qarhan Salt Lake,northwestern China

In terms of formation mechanisms of linear dunes,there are open arguments for their widespread distribution and multi-morphological diversities.In order to clarify the formation mechanism of linear dunes of Qarhan Salt Lake,we used pattern analysis method to analyze the statistical characteristics and spatial variation of their pattern parameters.Except at the west-northwest margin,the pattern parameters showed regular spatial variation from the up-middle part towards the downwind end of the dune field.Based on the cumulative probability plots for inter-crest spacing and crest length,we divided the linear dunes into three groups,which corresponding to the three evolution stages of these dunes.The first group comprises erosional relics,with shorter crests,smaller inter-crest spacing and more random dune orientation.The second group comprises dunes whose sand supply is just sufficient to maintain stability and these dunes are approaching the net erosion stage.The crest length and inter-crest spacing of these dunes are much larger than those of the first group,and dune orientation is closer to the resultant drift direction （RDD） .The last group comprises linear dunes that are still undergoing vertical accretion and longitudinal elongation,which follows the RDD of the modern wind regime.The presence of regular spatial variation of pattern parameters and a similar geometry with the vegetated linear dunes suggest that deposition and erosion coexist in the development and evolution of linear dunes of Qarhan Salt Lake,i.e.deposition predominates at the downwind end of linear dunes in the vertical accretion and longitudinal elongation stage,whereas erosion mainly occurs at the upwind end of linear dunes in the degradation stage.Therefore,the formation mechanism of linear dunes in Qarhan Salt Lake can be reasonably explained by the combination of depositional and erosional theories.

An Insight on Future Development Approaches of Salt Lake Magnesium Resources:from the Current Situation of China's Magnesium Industry

Magnesium-bearing minerals discovered on the earth so far occur mainly as solid or liquid.The former include magnesite(Mg CO3),dolomite(Mg CO3·Ca CO3),carnallite(Mg Cl2·KCl·6H2O),bischofite(Mg Cl2·6H2O)and

Aeolian component records in lacustrine sediments and its atmospheric circulation significance for evolution of Qarhan salt lake,NE Qinghai-Tibetan Plateau

1 Introduction The Qarhan Playa of Qaidam Basin is located at the northeastern QinghaiTibetan Plateau(QTP),in which thick lacustrine and evaporate sediments deposited since the late Pleistocene(Chen et al.,1985,1986).As surrounded by capacious Gobi and yardang fields and suffered strong westerly-northwesterly wind,abundant aeolian materials were trapped in these sediment sequences in the

In Search of Portable Water Supplies within a Brine and Mine Water-Invaded Region for Serving Some Communities around Ishiagu, Afikpo and Environs in Abakaliki Basin, Southeast Nigeria

The study investigates the hydrogeochemical characteristics of some towns in the Abakaliki Basin, comprising, Ishiagu, Aka Eze, Amaseri, Afikpo and Okposi communities, with the aim of sourcing for portable water in the area. The basin is underlain by Albian sediments, essentially shales, in the lowlands, which were affected by low-grade metamorphism that had produced slates. The highlands comprise basic intrusives from episodes of magmatism and metallic ore mineralisation. Injection of brines into the aquifer system and low, seasonal aquifer recharge from rainfall results in poor water quality in the area. The study analyzes the geochemical distribution in water sources in the area and identifies sources of pollutants to guide the better choice of portable water. Results of hydrogeochemical analysis of both surface and groundwater from the communities were compared with World Health Organization to identify portable water locations in the area. While the salt lake at Okposi is the main source of brine intrusion in the study area, the Pb/Zn mine at Ishiagu is the main source of mine-water pollution in the study area. Most chemical parameters, (especially Cl-, Na+, Ca2+, Mg2+, SO42-, HCO3-) maintain high concentrations within the salt lake area, with the values declining away from the salt lake. The main anthropogenic source of pollution in the area, especially at Ishiagu, is the indiscriminate surface mining of lead-zinc without proposer waste management practices. Possible sourcing for portable water in the study area includes a deep borehole at Ishiagu, away from lead-zinc intrusives. At the Okposi axis, searching for portable water in boreholes should target shallower aquifers that do not communicate with the deeper-seated brine zones, likewise targeting zones farther away from these brine-invaded areas. A controlled pumping rate could potentially ensure that the cone of depression was not low enough to reach the brine zone at depth. In addition, desalination could also potentially render the salt water drinkable if properly handled to eliminate the high concentration of salts in the water to the level of acceptable limit by the WHO. Based on the study, the best area to target for portable water in the study area is Afikpo, with most geochemical elements naturally occurring within WHO’s standard concentration while portable water could be harnessed in areas further away from mining sites, especially at deep groundwater.

内蒙古典型旱区盐湖盆地浅层地下水污染风险评价

为明晰内蒙古阿拉善盟吉兰泰盐湖盆地浅层地下水污染特征及评估地下水饮水安全风险等级,采集了盐湖盆地研究区土壤表层(0—10 cm)样品56个,地下水样品127个,检测分析土壤中重金属元素Cu、As、Pb含量及水样中Cr、Hg、As、F^(-)、NO_(2)^(-)、NO_(3)^(-)含量.运用地下水风险评价概念模型,将地下水脆弱性、地下水污染物容量及土壤毒性污染物潜在生态危害评价有机结合,对地下水污染风险展开评价.借助ArcGIS软件进行克里格插值绘图,探析盐湖盆地浅层地下水风险的空间分布特征.结果表明:盐湖盆地地下水脆弱性指数范围为4.80—5.30属于中等脆弱性,吉兰泰盐湖东南部和吉兰泰镇西北部脆弱性高于其他区域;地下水样品中重金属Hg的含量在《地下水质量标准》中Ⅲ类水水质标准范围内,其他元素均有超标现象,其中F^(-)超标率最高,为62.20%,Cr、As、F^(-)、NO_(2)^(-)、NO_(3)^(-)变异系数分别为125.40%、183.50%、178.70%、248.70%、280.70%,属于强变异性,受外界因素干扰较为明显,研究区地下水特征污染物分布较为集中,主要分布在盐湖盆地的东南部;土壤中重金属Cr、Hg、As的平均含量分别为26.32、0.17、11.77 mg·kg^(-1),与内蒙古当地土壤背景值相比较,Cr的平均值在背景值范围内,而Hg、As的平均值分别超出背景值4.25、1.57倍,土壤综合潜在生态危害指数为188.32,属于中等潜在生态危害,在盐湖盆地中有41.07%的样品点属于中等、强、很强潜在生态危害;盐湖盆地地下水污染风险等级分布不同与含水层脆弱性指数、特征污染物容量指数及潜在生态危害指数有关,较高污染风险区和高风险区分布在锡林高勒镇西部,较高风险以上的面积占研究区面积的25.77%,古拉本敖包镇、贺兰山的东南部在中风险范围内,中风险区面积占研究区面积的11.49%.

新疆库车盆地古近纪—新近纪盐湖成钾与靶区预测

库车前陆盆地位于塔里木盆地北部,属于副特提斯域,古近纪受副特提斯海海水补给,古近纪—新近纪发育巨厚蒸发岩。研究显示,库车盆地始新世和中新世古盐湖卤水已演化至钾盐析出阶段,在地层中广泛发现了原生钾盐矿物,如钾石盐、光卤石、杂卤石等;通过岩芯岩屑地球化学及矿物学分析,基本确定了至少3个富钾层或成钾层位,其中始新统中上部两个和中新统中上部一个,钾离子含量最高达3%,另外,上新统可能存在一个成钾层位。本文在综述此前库车盆地构造、蒸发岩、盐类矿物学、地球化学与盐湖沉积等研究基础上,建立了新的库车盆地古盐湖构造-沉积演变、成钾模式;提出了4个钾盐成矿区带,即北部克拉苏成矿带、中部秋里塔克成矿带、南部沙雅构造沉降成矿带以及东部阳霞凹地成钾区,这些关键认识为库车盆地的钾盐勘查提供了重要的理论和科学依据。

柴达木盆地东陵湖水化学特征与钾盐分布研究

东陵湖位于柴达木盆地大型钾盐富集基地察尔汗盐湖北部,其浅部石盐层中伴生有光卤石沉积,地勘工作揭示东陵湖浅部边缘地带有寻找低品位固体钾矿的潜力。本文以东陵湖湖表卤水、钻孔晶间卤水、承压卤水、浅层钻孔(0~8 m)盐类沉积物为研究对象,分析研究了东陵湖卤水水化学特征、钻孔沉积物特征及钾盐分布规律,在对比分析察尔汗盐湖钾矿分布特征的基础上,对研究区钾盐成矿作用进行了探讨,主要得出以下结论:①东陵湖周边凹地钻孔的晶间卤水K^(+)平均含量最高(3.19 g/L),其次为凹地钻孔承压卤水(1.46 g/L),湖表卤水(0.74 g/L)和湖区钻孔晶间卤水(0.79 g/L)K^(+)含量较低;东陵湖卤水样品矿化度(TDS)变化范围较大,介于80.63~547.11 g/L之间,不同卤水样品的TDS与K^(+)含量无明显正相关性。②东陵湖钻孔揭露含盐地层厚4.2~6.4 m,岩性以石盐为主,局部含有光卤石沉积,偶见钾石盐;光卤石呈层状和浸染状分布,与石盐呈韵律结构。③东陵湖液体钾矿主要分布于湖区西南侧,卤水K^(+)含量为4.33~6.29 g/L,KCl品位介于0.21%~0.47%之间;固体钾矿主要分布于湖区南侧,沉积物钾含量为2.05%~4.86%,KCl含量介于3.92%~9.29%之间。④东陵湖光卤石沉积区与察尔汗盐湖层状光卤石均沿北缘深大断裂带分布,且后者主要分布于北缘氯化物型水和南缘硫酸镁亚型水混合区域,即达布逊和别勒滩两个洼地北缘,结合Na^(+)、K^(+)、Mg^(2+)、Ca^(2+)//Cl-H_(2)O体系相图和K^(+)-Ca^(2+)相关性分析,认为沿东陵湖南侧深大断裂带补给的Ca-Cl水促进了东陵湖光卤石的沉积。

中国含盐盆地卤水溴元素分布与物源

中国含盐盆地赋存丰富的盐湖卤水和深部卤水资源,卤水中富集溴(Br)元素,具有潜在的开发利用价值。Br作为盐湖卤水中重要的资源元素,目前对其分布规律和物质来源的系统对比研究鲜有报道。本文以柴达木盆地察尔汗盐湖四个区段晶间卤水为研究对象,分析整个湖区Br元素分布规律和物质来源,对比中国不同含盐盆地卤水Br资源变化和物源联系,并总结不同卤水开发利用价值。结果表明:①察尔汗盐湖Br含量呈东高西低特征且不同区段差异明显;②别勒滩和达布逊区段卤水低Br受河流补给并经蒸发富集,而察尔汗和霍布逊区段高Br受北部断裂带上涌富Ca泉水补给;③中国含盐盆地(柴达木盆地、库车盆地、江汉盆地、吉泰盆地)大部分深部卤水高Br值主要受水-岩反应、沉积物及有机质中Br的解吸获得;④盐湖晶间卤水虽远不及深部卤水Br含量高,但其优点在于便于开发、综合利用率高,尤其浓缩卤水及老卤中的Br含量可预见性的高于工业开采品位,是当下和今后值得关注的资源。

青海柴达木巴伦马海盆地盐湖黏土型钾锂矿的物质组成及溶矿试验研究

为评价柴达木巴伦马海盆地盐湖黏土型钾锂矿可加工性和可利用性,开展了X射线衍射分析、TOFSIMS(飞行时间二次离子质谱)元素面扫描分析等岩矿测试和溶矿试验。结果表明:盐湖黏土型钾锂矿主要矿物类型为造岩矿物碎屑、盐类矿物、吸附于矿物表面或层状矿物结构面的物质。主要化学成分为K、Na、O、Cl,盐类矿物成分Cl^(-)、SO_(4)^(2-)、K、Ca、Na、Mg、B_(2)O_(3)含量高,稀有元素Li、Rb、Cs、Sr富集明显。黏土层中水可溶物为石盐、光卤石和水氯镁石,Li、K可以通过水溶方式溶取利用。分析认为K的赋存类型主要为可溶性盐类矿物、长石和黏土矿物;锂的赋存类型主要为吸附锂和结构型锂,吸附锂包括水溶锂和酸浸锂,残渣态锂属于结构型锂。溶矿试验显示巴伦马海盐湖黏土型钾锂矿中K达到固体矿工业指标,Li达到液体矿综合评价指标,证实是可采出、有价值、可加工、可利用的矿产,估算潜在LiCl资源为114.41万t,KCl资源为1395.22万t。推荐Li≥32.25×10^(-6)为黏土型钾锂矿的锂综合利用品位。

Porosity Distribution Characteristics and Geological Analysis of Brine Storage Medium in the Qaidam Basin, Western China

Underground brine is an unusual water resource that contains abundant mineral resources. It is distributed widely in the Qaidam Basin, western China, a hyperarid inland basin located in the northern Tibetan Plateau. Pores in the brine storage medium act as storage space and transmission channels of underground brine. Therefore, the porosity of brine storage medium determines its ability to store brine. In this study, Mahai Salt Lake was used as the research area as a modern saline lake located in the north area of the Qaidam Basin. A total of 100 porosity samples were collected from eight sampling points in two profiles of the research area at sampling depths of 1.30–314.78 m. The porosity distribution characteristics and influencing factors in brine storage medium were analysed according to the measured porosity data. Based on analysis of the pore structure characteristics, the brine storage medium contains intercrystalline pores, unlike conventional freshwater storage mediums. Moreover, the primary salt rock is susceptible to dissolution by lighter brine, facilitating the formation of secondary porosity. Due to the formation of secondary pores, a porosity greater than 20% remains even at buried depths greater than 100 m. Based on the geological statistical analysis, due to the geographic location, salt formation time, and depositional environment, the porosity values of Mahai Salt Lake do not exhibit a wider distribution, but also show more extreme values than a nearby salt lake. Based on the porosity characteristics by depth, due to the presence of secondary pores, flooding, stratigraphic static pressure, and other factors, porosity shows fluctuations with increasing depth.

柴达木盆地一里坪富锂卤水储层非均质性及对卤水开采的影响

在盐湖卤水长期的研究和开采工作中,储层非均质性的问题极少被关注。随着深部卤水的利用强度加大,难开采卤水储层非均质性的问题逐渐受到重视。以柴达木盆地一里坪富锂卤水储层为研究对象,根据其储层的岩性和展布特征,从垂向和平面两个角度进行了探索性的研究。结果表明,浅部第Ⅰ卤水矿层储层的非均质性弱于深部,晶间型卤水储层非均质性略弱于孔隙型卤水储层。平面上,非均质性弱的深部优质储层主要位于研究区东北部,单个连续的富水储集体延伸范围多变,常为300~800 m。因此,应优先在非均质性弱的东北部布置采卤工程,并根据富水储集体的展布特征优化开采井的深度和间距,提高开采效率。

西北盐湖流域地下水重金属的污染特征及健康风险

为探究西北内陆盐湖流域地下水中重金属元素的分布特征及对人体健康的潜在风险,以内蒙古吉兰泰盐湖盆地重金属风险区域为研究对象,采集地下水样并测试分析pH、TDS、8种离子等物化指标及Cr^(6+)、Cu、Zn、As、Cd和Pb等重金属含量,揭示重金属空间分布特征,解析重金属分布控制因素,评价重金属污染风险水平,检验离子同源性及判别健康风险程度.结果表明,盐湖流域地下水中重金属元素平均浓度大小依次为Cr^(6+)>Zn>Cu>As>Pb>Cd,其中局部区域出现Cr^(6+)和As超出地下水质量标准(GB/T 14848—2017)Ⅲ类水标准限值;地下水中重金属含量分布具有显著的空间差异性,高值区主要集中流域西北侧和盐湖盆地西南侧;流域地下水总体处于安全清洁的状态,仅在东南部分区域出现轻度污染,不存在中度和重度污染;Cr^(6+)、Cr和Cu具有一定的同源性,Zn、Cd和Pb来源相似或迁移转化过程相近,地下水重金属的分布主要受岩土矿物、气象和水文因素等天然因素的影响,多种离子成分因相似的环境地球化学作用控制而迁移演化;化学致癌重金属通过饮水途径对人体健康风险超过非致癌物,儿童接触重金属后导致的健康风险比成人高;区域Cr^(6+)健康风险值6.2×10−5 a−1小于美国环保署(US EPA)但大于国际辐射防护委员会(ICRP)推荐的最大可接受风险水平,非致癌物重金属平均健康风险呈现出Cu>Pb>Zn,均远低于ICRP推荐的最大可接受水平.

吉兰泰盐湖盆地土壤颗粒分形特征与空间变异分析

[目的]阐明盐湖盆地流域土壤颗粒分形特征和空间变异特征,揭示区域土壤环境演变和影响因子的响应规律,为旱区盐湖流域沙害治理提供数据和理论支持。[方法]以吉兰泰盐湖盆地流域为研究区,布设50个土壤采样点,采集表层、50 cm、100 cm土层150个土壤样本,基于土壤粒径分布和土壤基本理化指标pH值、总溶解性固体TDS、总氮TN、含水率θ的测试数据,采用多因素相关分析的方法,分析了土壤分形维数与各粒级含量和土壤基本理化因子的相关性;应用地统计学方法对土壤剖面分形维数空间变异特征及分布规律开展了研究。[结果]研究区0—100 cm土壤质地以砂土、壤砂土为主,不同土层深度土壤质地类型基本一致,土壤颗粒分形维数D值为1.672~2.785。土壤分形维数与黏粒和粉粒呈极显著正相关,与粗砂、中砂、细砂呈显著负相关,0.1 mm粒径是D值随土壤粒径变化的分界值。D值与含水率、总氮在3土层均呈现显著正相关,而与pH值和TDS相关性不显著。土壤分形维数具有强烈的空间自相关性,各层土壤D值均呈现出由南向北逐渐增大的条块状镶嵌分布特征,流域北部的巴音乌拉山和乌兰布和沙漠地区是D值的高值区,西南部边缘的图格力高勒沟台地和东南部边缘的贺兰山地区是全流域D值的最低区域,土壤表层在吉兰泰盐湖附近有带状分布的高值区。[结论]受气候和人类活动的影响,吉兰泰盐湖盆地土壤质地发生变化,表层土壤颗粒风蚀严重,较深层土壤具有粗粒化现象,未来应加强土壤侵蚀和退化状况观测研究。

柴达木盆地马海盐湖地下卤水地球物理探测及应用

柴达木盆地盐湖地区地下卤水资源储量丰富,含卤水层具有孔隙度较小、非均质、各向异性较强及富卤水性能差异较大等特征。为精准探测马海盐湖地下卤水富集区域,获取盐岩分布密度差异性变化区间,针对柴达木盆地马海盐湖地区特有的盐岩介质、晶间高矿化度卤水,以及孔隙储卤、裂隙与断层控卤等多种储卤模式并存的地质条件,采用了包括抽水试验和高精度重力探测法、音频大地电磁探测法、高分辨率地震探测法的多尺度、多种物探方法对结晶盐层与富卤水地层进行了探测。抽水试验的结果表明,K_(12)、K_(13)、K_(14)等井组所处的卤水富集区Ⅰ出水量为37297 m^(3)/d,T_(1)、K_(1)、K_(4)等井组所处的卤水富集区Ⅱ出水量为35736 m^(3)/d;基于抽水试验和多种地球物理探测信息集成技术,确定了两处可实现持续与稳定开采的地下卤水富集区域,并刻画其地层结构与地质构造。

旱区盐湖盆地土壤重金属空间变异及对土壤理化因子的响应

为探明盐湖盆地土壤重金属铬(Cr)、汞(Hg)、砷(As)的分布特征及在其理化因素影响下呈现的分异规律,以内蒙吉兰泰盐湖盆地为研究区,采集土壤表层、50 cm、100 cm等不同土层深度150个样本,对Cr、Hg、As和土壤理化指标进行测试,以地统计学解析不同剖面土壤重金属空间变异特征及分布规律,运用多元统计和冗余分析法解释土壤中各土层重金属与土壤pH、TDS、TN、θ、土壤分形维数D等理化指标的赋存相关性。结果表明,土壤重金属Cr、Hg、As含量分别介于2.90-63.5、0.002-0.602、0.02-21.8 mg·kg^(-1)之间,变幅较大;Cr、Hg、As的内蒙古地区背景值均在各层最大值和最小值之间,存在Cr、Hg、As的超标点或局部超标区域;各层土壤的Cr、Hg、As含量均在国家土壤污染风险管控标准范围之内;各土层Cr、Hg和100 cm处As的空间分布特征具有强烈的空间自相关性,土壤母质、气候环境等自然因素是土壤Cr、Hg、As含量的主要影响因素;As在表层、50 cm层属中等程度的空间自相关,空间变异是自然因素和随机因素的协同作用驱动所致;各层土壤理化指标对重金属变异特征影响效应具有相同的规律,贡献率排序D>p H>TDS>TN>θ,其中土壤分形维数D对土壤重金属的影响起主导性作用;在所有土层中分形维数对Cr、As产生正向影响,对Hg产生负向影响,达到极显著水平0.002(P<0.01)。研究成果可为旱区盐湖盆地土壤污染修复提供技术支持,为保护区域生态环境安全提供理论依据。

青海柴达木盆地盐湖资源保障能力分析与对策研究

柴达木盆地盐湖资源在保障我国粮食安全、支撑新能源及新材料产业发展中处于重要的战略地位。为了贯彻落实习近平总书记“加快建设世界级盐湖产业基地”的重大要求,走可持续发展之路,对提高盐湖资源保障能力提出了更高的要求。本文通过综合研究,采用静态保障年限计算方法对柴达木盐湖资源各矿种的保有资源储量数据进行了保障程度分析,以柴达木盐湖资源保障存在的问题和建设世界级盐湖产业基地对盐湖资源的需求为导向,探讨了保障盐湖资源接续储备的实施路径。本次研究认为,柴达木盐湖资源中仅镁盐、钠盐资源保障程度很高,钾盐、锂矿、硼矿资源保障程度中等偏低,盐湖资源接续保障问题突出。基于以上研究结果,从加快接续资源选区评价工作、加强盐湖资源综合高效利用、健全盐湖资源保护利用与储备体系等三方面提出了提高盐湖资源保障与接续储备能力实现路径。