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1.
Despite continued uncertainty about the physical realities and political, economic and social implications of peak oil, combined concerns about oil scarcity, climate change and globalisation has spawned an energetic relocalisation movement dedicated to achieving a comprehensive reduction in oil dependency through community-scale initiatives. This paper uses a discourse approach to examine the emergence, geographical spread and practices of the Transition Network, a UK-originated relocalisation movement now involving 186 local initiatives in the UK and other countries. We trace the movement’s drawing upon, and innovation from, discourses and techniques used by other grassroots environmental movements to promote a spatial representation of peak oil as an inevitable and geographically undiscriminating problem, and its use of addiction metaphors and participatory techniques to promote personal and community-scale energy descent initiatives as a viable and necessary alternative to globalisation. We also analyse the spatial representations and techniques used in the Network’s “rhizomic” spread across multiple localities around the world and embedding in communities where relocalisation initiatives are established. We conclude by examining the future challenges these spatial constructions of peak oil pose for the relocalisation movement.  相似文献   

2.
Density stratification in saline and hypersaline water bodies from throughout the world can have large impacts on the internal cycling and loading of salinity, nutrients, and trace elements. High temporal resolution hydroacoustic and physical/chemical data were collected at two sites in Great Salt Lake (GSL), a saline lake in the western USA, to understand how density stratification may influence salinity and mercury (Hg) distributions. The first study site was in a causeway breach where saline water from GSL exchanges with less saline water from a flow restricted bay. Near-surface-specific conductance values measured in water at the breach displayed a good relationship with both flow and wind direction. No diurnal variations in the concentration of dissolved (<0.45 μm) methylmercury (MeHg) were observed during the 24-h sampling period; however, the highest proportion of particulate Hgtotal and MeHg loadings was observed during periods of elevated salinity. The second study site was located on the bottom of GSL where movement of a high-salinity water layer, referred to as the deep brine layer (DBL), is restricted to a naturally occurring 1.5-km-wide “spillway” structure. During selected time periods in April/May, 2012, wind-induced flow reversals in a railroad causeway breach, separating Gunnison and Gilbert Bays, were coupled with high-velocity flow pulses (up to 55 cm/s) in the DBL at the spillway site. These flow pulses were likely driven by a pressure response of highly saline water from Gunnison Bay flowing into the north basin of Gilbert Bay. Short-term flow reversal events measured at the railroad causeway breach have the ability to move measurable amounts of salt and Hg from Gunnison Bay into the DBL. Future disturbance to the steady state conditions currently imposed by the railroad causeway infrastructure could result in changes to the existing chemical balance between Gunnison and Gilbert Bays. Monitoring instruments were installed at six additional sites in the DBL during October 2012 to assess impacts from any future modifications to the railroad causeway.  相似文献   

3.
The Transition Movement, originating in Ireland and the United Kingdom, gathers and supports community-led actions to meet the global challenges of climate change, peak oil and energy descent. In our study we analysed a Transition Network project, a Danish village built from scratch by its inhabitants and named the Self Sufficient Village (SSV). Employing the theories of constructed landscapes and place attachment, we studied how the Transition Movement ideology shaped the constructed landscape of the village and influenced the inhabitants’ attachment. The research team, following the grounded theory approach, conducted a field study staying in SSV. We collected data with focus groups, individual interviews and participatory observations, taking part in daily life of the community. The analysis revealed three, intertwined themes which altogether create the constructed landscape of SSV. They were named Community, Ideology, and Individual impact, respectively. Our findings showed that the community and strong social ties were predominant factors in shaping place attachment. Transition ideology and environmental awareness, although less pronounced, still turned out to be vital for the feelings of belongingness and empowerment, resulting in a positive impact of the village on the local scale. Using our case study as an example we discuss the importance of environmental concern and place attachment for similar grass-root initiatives.  相似文献   

4.
察尔汗盐湖物质来源的研究   总被引：4，自引：1，他引：3  
柴达木盆地察尔汗盐湖是一个以氯化物为主的盐湖,然而今天补给该盐湖的水是碳酸盐和硫酸盐型的。所以,该盐湖的物质来源问题是研究其成因的根本问题,也一直是中外学者感兴趣。同时又感到非常棘手的问题,他们提出了各种假说。本文综合了六化学、岩相古地理、Sr和Br的地球化学、古生态、同位素和构造方面的资料,对前人提出的各种假说逐一进行了论证,最后的结论是,察尔汗盐湖的盐类物质有三个来原:通过河流补给的地表化学风化淋滤物质、通过断层补给的油田水和柴达木古湖的遗留物质。否定了海水来源和第三纪含盐系风化淋滤来源的假说。 中更新世末,察尔汗湖从柴达木古湖中完全蚀立出来,并继承了部分从古湖遗留下来的盐类物质。在察尔汗湖蚀立过程中和独立后早期,构造运动比较强烈,通过断层补给的油田水较多,后来随着构造运动的减弱,油田水补给量逐渐减少,而地丧化学风化淋滤物质的补给一直是比较稳定的。  相似文献   

5.
The Bonneville Basin is a continental lacustrine system accommodating extensive microbial carbonate deposits corresponding to two distinct phases: the deep Lake Bonneville (30 000 to 11 500 14C bp ) and the shallow Great Salt Lake (since 11 500 14C bp ). A characterization of these microbial deposits and their associated sediments provides insights into their spatio‐temporal distribution patterns. The Bonneville phase preferentially displays vertical distribution of the microbial deposits resulting from high‐amplitude lake level variations. Due to the basin physiography, the microbial deposits were restricted to a narrow shoreline belt following Bonneville lake level variations. Carbonate production was more efficient during intervals of relative lake level stability as recorded by the formation of successive terraces. In contrast, the Great Salt Lake microbial deposits showed a great lateral distribution, linked to the modern flat bottom configuration. A low vertical distribution of the microbial deposits was the result of the shallow water depth combined with a low amplitude of lake level fluctuations. These younger microbial deposits display a higher diversity of fabrics and sizes. They are distributed along an extensive ‘shore to lake’ transect on a flat platform in relation to local and progressive accommodation space changes. Microbial deposits are temporally discontinuous throughout the lake history showing longer hiatuses during the Bonneville phase. The main parameters controlling the rate of carbonate production are related to the interaction between physical (kinetics of the mineral precipitation, lake water temperature and runoff), chemical (Ca2+, Mg2+ and HCO3? concentrations, Mg/Ca ratio, dilution and depletion) and/or biological (trophic) factors. The contrast in evolution of Lake Bonneville and Great Salt Lake microbial deposits during their lacustrine history leads to discussions on major chemical and climatic changes during this interval as well as the role of physiography. Furthermore, it provides novel insights into the composition, structure and formation of microbialite‐rich carbonate deposits under freshwater and hypersaline conditions.  相似文献   

6.
新疆乌勇布拉克盐湖的形成及硝酸钾矿床特征   总被引：2，自引：0，他引：2  
黄铁栋 《新疆地质》2005,23(1):36-40
详细论述乌勇布拉克盐湖的沉积的全过程,并将其划分成3个阶段,每阶段沉积物都有自己的特点,但总体趋势是由机械沉积过渡到化学沉积,通过蒸发试验和“干盐湖”理论进一步确定钾硝石矿产牛在当代干盐湖向沙下湖转化阶段．乌勇布拉克盐湖固相、液相KNO3矿体特征具有代表性,对其他盐湖钾盐找矿有指导意义．  相似文献   

7.
西藏扎布耶碳酸盐型盐湖卤水相化学研究   总被引：12，自引：0，他引：12  
中国盐湖资源丰富,且水化学类型齐全。西藏扎布耶盐湖位于西藏高原腹地,该湖卤水水化学类型为碳酸盐型,已处于盐湖演化晚期,是一个固液共存的盐湖矿床,具有很好的工业开发价值。笔者分别在15℃、25℃下对该卤水进行了等温蒸发实验,研究了在此两个温度下卤水中各元素富集行为和盐类矿物析出规律。并通过讨论其与国内外碳酸盐型和硫酸盐型锂盐湖的卤水蒸发路径和矿物析出异同,指出扎布耶盐湖具有其独特的卤水蒸发析盐路径。在本实验中低温有利于卤水中锂的富集,而高温有利于硼的富集,碳酸锂和钾盐交叉析出,低温时钾的矿物主要为钾石盐,高温时主要为钾芒硝,高温有利于获得高品位的碳酸锂混盐。  相似文献   

8.
1976-2017年青藏高原可可西里盐湖面积动态变化及成因分析   总被引：1，自引：0，他引：1  
青藏高原湖泊是全球气候变化的敏感指示器。近56年来,可可西里地区气候呈显著暖湿化趋势,其中气温上升速率为0.33℃·（10a）-1（R=0.746,P<0.01）,降水增加速率为23.4mm·（10a）-1（R=0.422,P<0.01）。近40年来,盐湖面积总体呈增大趋势,其中,1976-2011年溃堤前盐湖面积以1.63 km2·a-1的速率扩大,溃堤后以8.51 km2·a-1的速率持续扩大。总体来看,近40多年来,盐湖面积先后经历了缓慢增大（1976-2011年）→急剧增大（2012-2013年）→稳定增大（2014-2017年）三个阶段。盐湖面积前期缓慢扩大的主要原因是可可西里地区气候暖湿化的结果,而后期面积急剧扩大的主要原因是因为2011年9月15日盐湖上游的卓乃湖溃堤,导致下游的3个湖泊（库赛湖、海丁诺尔湖和盐湖）串连成一体;冰川和冻土融水可能是引起可可西里盐湖面积扩张的原因,但并非主要原因。后期盐湖面积还将呈稳定增大趋势。盐湖面积扩大导致盐湖湖水淡化,周边草地受到淹没破坏的面积不断扩大,这种变化不仅对其周边草地生态环境产生破坏,还可能对可可西里周边重大工程设施产生不利影响。鉴于盐湖面积今后还将持续增大,并对其周边重大工程设施产生不利影响。因此,应用多源卫星资料对盐湖进行长期持续的跟踪观测仍将是相关政府部门关注的重点。  相似文献   

9.
王弭力  郭立鹤 《地球学报》1988,10(1):187-193
本文对自然界极为少见、产于青海柴达木盆地的半水石膏的矿物特征进行了详细研究,并引用实际资料及理论依据,对其成因进行了探讨。  相似文献   

10.
马海盐湖是柴达木盆地一个重要的成钾盐湖,本研究对该盐湖区隐伏控卤构造开展遥感识别研究,利用LANDSAT光学遥感数据和PALSAR雷达遥感数据,采用了光学遥感假彩色合成影像解译和雷达遥感数据干涉分析,解译了研究区的构造,识别出研究区一级构造三条,二级的构造若干条.并通过在干盐湖区遥感构造识别及构造应力分析,判定了2条一级压性构造和1条一级张性构造,对解译的构造进行野外查证,压性构造和张性构造野外特征明显,同时受构造几何形态影响,同一断裂不同部位断裂性质会发生变化,张性应力的位置除与构造性质有关外,也与构造几何特征有关,并进行了野外查证.本次研究结合已知卤水矿和浅表给水度和含钾率的分析,最终圈定出两个具有潜力的遥感预测靶区.  相似文献   

11.
本文采用多接收电感耦合等离子体质谱法(MC-ICP-MS),对柴达木盆地一里坪15YZK01钻孔中前336.2 m含石盐地层中的7个石膏样品进行230Th定年。依据年代-深度公式,获得S1-S4盐层的成盐年代分别为733.8~716.0 ka、581.9~573.8 ka、181.6~179.3 ka和158.0~154.2 ka;含芒硝粉砂地层的年代为171.6 ka。结合前人对一里坪表面盐壳的14C测年数据,证实一里坪表面盐层S5开始形成于末次冰期。15YZK01钻孔记录的成盐期与青藏高原第四纪冰期及构造运动存在一定的对应关系:石盐层S1对应于"昆黄运动"之后的望昆冰期,以及深海氧同位素第18阶段(MIS18);S2对应于大间冰期,但是该年代比较接近望昆冰期;S3和S4石盐层及含芒硝粉砂层对应于共和运动和倒数第二次冰期MIS6;S5石盐层开始形成的时代对应于末次冰期MIS2。同时,通过对柴达木盆地多个钻孔含盐地层的测年数据进行总结,证实中更新世以来青藏高原冰川活动与柴达木盆地盐类沉积存在着一定的对应关系。柴达木盆地西北部的成盐盆地中通常发于有倒数第二次冰期和末次冰期的石盐层;而盆地东南部的察尔汗盐湖区仅发现有末次冰期以来的石盐层。柴达木盆地成盐期受到青藏高原第四纪冰期和构造运动的影响,第四纪冰期中盐湖水源补给量的减少,是导致柴达木盆地成盐的重要驱动因素。  相似文献   

12.
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.  相似文献   

13.
Some inclusions from Salt Lake Crater are essentially single-phase subcalcic clinopyroxenites whose original clinopyroxenes, prior to extensive unmixing, were tschermakitic subcalcic varieties with compositions close to Ca34Mg54Fe12. In addition to copious amounts of orthopyroxene, very minor garnet and spinel also were exsolved from the subcalcic clinopyroxenes.The genesis of the garnet pyroxenite suite at Salt Lake Crater has been examined in terms of three models, namely: (i) cumulates from alkali basaltic magmas; (ii) fractional fusion of basanitic garnet clinopyroxenite; and (iii) anatexis of upper mantle lherzolites. Field, mineralogical, chemical and experimental data collectively favour model (iii) and indicate that the nodules are genetically unrelated to their nephelinitic hosts. The Salt Lake garnet pyroxenites can be closely equated with the garnet pyroxenites in magmatictype layers in certain alpine-type ultramafic massifs and they are also similar to many garnet pyroxenite xenoliths in alkaline volcanics from other localities.Liquids produced by anhydrous partial melting of spinel Iherzolite at pressures of approximately 20 kb commonly have picritic chemistries. The crystallization behaviour of picritic liquids at elevated pressures ( 20 kb) indicates that the initial crystallization products may be either essentially single-phase subcalcic clinopyroxenites (with minimal high pressure fractionation) or a range of olivine-aluminous orthopyroxene-aluminous subcalcic clinopyroxene-garnet-(spinel) assemblages with variable 100 Mg/(Mg+Fe) ratios (when fractionation has been operative). All these assemblages may be subsequently modified by subsolidus exsolution and recrystallization.  相似文献   

14.
侯马-运城盆地为晚新生代以来强烈下沉的盆地,现今却大面积遭受剥蚀,有悖于构造下沉接受沉积的常理。为探究其原因,在对侯马-运城盆地及邻区20多个黄土剖面进行野外测量及年代对比的基础上,选择运城盐湖北缘进行连续钻探,开展钻孔岩芯的粒度、磁化率、色度、烧失量及微量元素环境替代性指标分析,并进行光释光及磁性地层学综合定年,同时与前人在侯马-运城盆地的近50个钻孔进行了对比。结果表明,盐湖钻孔200 m岩芯代表了大约距今0.7 Ma以来的沉积。55~200 m深度（约距今0.2~0.7 Ma）岩芯反映受气候旋回影响为主的宽阔河湖沉积环境,指示侯马-运城盆地曾与邻近的渭河盆地、三门盆地连成浩瀚的汾渭古湖;55 m深度以上（约0.2 Ma以后）突然转为以河流相为主的沉积环境,这是由于三门峡谷河流溯源侵蚀贯通三门盆地,导致湖水下泄,使盆地发生大面积湖退,从长期沉积转向广泛剥蚀,并被S2以来黄土/古土壤披盖。研究区盆岭空间分布分析揭示,早期北东东向隆起-凹陷被晚期北北东向隆起-凹陷叠加,隆起叠加处构成较强抬升区（峨嵋台地等）,披盖不同时期的黄土或古土壤;凹陷叠加区则构成强烈沉降区,如运城盐湖因强烈下沉而封闭和咸化。其构造叠加可能与鄂尔多斯地块运动方式有关。距今约8 Ma前,青藏地块向东北方向与鄂尔多斯地块发生强烈碰撞,在来自青藏高原深部地幔流的配合下,可能使鄂尔多斯地块向东北方向移动,一方面使北东东向汾渭盆地进一步拉张;另一方面与华北克拉通构成右旋力偶,拉裂成北北东雁行排列的山西地堑系。两者于侯马-运城盆地叠加,形成隆起与凹陷的叠加构造地貌格局。  相似文献   

15.
通过对罗布泊北部卤水依据不同温度下的Na~+、K~+、Mg~(2+)||Cl~-、SO_4~(2-)—H_2O体系相图分析,分别给出氯化钠、氯化钾、硫酸钾、一水硫酸镁综合开发利用罗布泊卤水的原则性工艺流程,并提出了在不同的生产阶段科学的工艺路线。这一具有较高的回收率和产品质量,为开发利用罗布泊北部卤水提供了理论依据。  相似文献   

16.
Firstly,the macroscopic chemical equilibrium state of a series of chemical reactions between intercrystal brine and its media salt layer (salt deposit) in Qarhan Salt Lake was studied by using the Pitzer theory.The concept of macroscopic solubility product and its relation with accumulated ore dissolving ratio were presented,which are used in the numerical model of dissolving and driving exploitation of potassium salt in Qarhan Salt Lake.And secondly,with a model forming idea of transport model for reacting solutes in the multi-component fresh groundwater system in porous media being a reference,a two-dimensional transport model coupled with a series of chemical reactions in a multi-component brine porous system (salt deposits) was developed by using the Pitzer theory. Meanwhile,the model was applied to model potassium/magnesium transport in Qarban Salt Lake in order to study the transfer law of solid and liquid phases in the dissolving and driving process and to design the optimal injection/abstraction strategy for dissolving and capturing maximum Potassium/ Magnesium in the mining of salt deposits in Qarban Salt Lake.  相似文献   

17.
Firstly, the macroscopic chemical equilibrium state of a series of chemical reactions between intercrystal brine and its media salt layer (salt deposit) in Qarhan Salt Lake was studied by using the Pitzer theory. The concept of macroscopic solubility product and its relation with accumulated ore dissolving ratio were presented, which are used in the numerical model of dissolving and driving exploitation of potassium salt in Qarhan Salt Lake. And secondly, with a model forming idea oftransport model for reacting solutes in the multi-component fresh groundwater system in porous media being a reference, a two-dimensional transport model coupled with a series of chemical reactions in a multi-component brine porous system (salt deposits) was developed by using the Pitzer theory.Meanwhile, the model was applied to model potassium/magnesium transport in Qarhan Salt Lake in order to study the transfer law of solid and liquid phases in the dissolving and driving process and to design the optimal injection/abstraction strategy for dissolving and capturing maximum Potassium/Magnesium in the mining of salt deposits in Qarhan Salt Lake.  相似文献   

18.
Modern fluvial meander plains exhibit complex planform transformations in response to meander‐bend expansion, downstream migration and rotation. These transformations exert a fundamental control on lithology and reservoir properties, yet their stratigraphic record has been poorly evaluated in ancient examples due to the lack of extensive three‐dimensional exposures. Here, a unique exhumed meander plain exposed to the north of Scarborough (Yorkshire, UK) is analysed in terms of architecture and morphodynamics, with the aim of developing a comprehensive model of facies distribution. The studied outcrop comprises tidal platforms and adjacent cliffs, where the depositional architecture of un‐tilted deposits was assessed on planform and vertical sections, respectively. In its broader perspective, this study demonstrates the potential of architectural mapping of extensive planform exposures for the reconstruction of ancient fluvial morphodynamics. The studied exhumed meander plain is part of the Scalby Formation of the Ravenscar Group, and originally drained small coastal incised valleys within the Jurassic Cleveland Basin. The meander plain is subdivided into two storeys that contain in‐channel and overbank architectural elements. In‐channel elements comprise expansional and downstream‐migrating point bars, point‐bar tails and channel fills. Overbank elements comprise crevasse complexes, levées, floodplain fines and lake fills. The evolution of the point bars played a significant role in dictating preserved facies distributions, with high flood‐stage nucleation and accretion of meander scrolls later reworked during waning flood‐stages. At a larger scale, meander belt morphodynamics were also a function of valley confinement and contrasts in substrate erodibility. Progressive valley infilling decreased the valley confinement, promoting the upward transition from prevalently downstream migrating to expansional meander belts, a transition associated with enhanced preservation of overbank elements. Strikingly similar relations between valley confinement, meander‐bend transformations and overbank preservation are observed in small modern meandering streams such as the Beaver River of the Canadian prairies and the Powder River of Montana (USA).  相似文献   

19.
Halite precipitation with water and air temperature was observed in detail,and homogenization temperature of fluid inclusions in halite formed in ancient and modem Chaka Salt Lake was studied.Halite precipitates mainly in August every year and largely precipitates between 13 and 15pm at one day when water temperatures reach 20℃but can seldom reach 30℃.Homogenization temperatures of fluid inclusions in halite formed in Chaka Salt Lake range from 14℃to 38℃with an average of 23.7℃.The number of inclusions appears an obvious peak value at homogenization temperatures between 18～25℃,which probably represent the water temperature in which halite mainly precipitates when water temperatures reach 20℃.Therefore,homogenization temperatures of fluid inclusions in halite formed in Chaka Salt Lake can well reflect the water temperature.  相似文献   

20.
郑浩  赵海香  谭红兵 《矿床地质》2023,42(2):411-424
麻米错盐湖是西藏境内发育的特大型锂矿床之一,目前对该盐湖的Li、B来源仍存在一定争议。文章系统采集麻米错盐湖水及周边补给水体样品,分析其主量元素特征,并使用多种水化学手段进行讨论,同时对盐湖水、河水及地热水进行蒸发模拟。结果表明,研究区河水及泉水中的主要离子受控于流域内岩石风化作用,其中碳酸盐岩矿物与蒸发岩矿物贡献最大,其次是硅酸盐矿物。文章对补给水体输入盐湖的Li、B资源进行定量计算,得出单纯通过河水和泉水的输入无法形成盐湖目前的探明储量。选择西藏地区最为富Li的地热水同补给水体按照一定比例混合后进行蒸发模拟,发现其析盐序列与盐湖水的析盐序列存在很大程度上的重叠,以上均证明麻米错盐湖中的Li、B资源除受到周边河水及泉水的补给外,还受到地热水的补给。  相似文献   

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