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1.
龙湖周边机井开采对地下水流影响的数值模拟 总被引:2,自引:0,他引:2
人工湖、库和河流等将改变区域水文循环过程,特别是地表水与地下水交换关系。本文对郑州市规划的龙湖入渗水利用和龙湖周边机井布设方案进行比较分析。龙湖水体形成后,湖区与周围地下水位的2.5m落差将使湖水大量入渗补给地下水,大范围抬升湖区周围地下水位,龙湖周围低洼处将有发生盐碱化的危险,威胁到紧靠龙湖的西部国家森林公园和规划中的东北部生态回廊绿地。本文利用美国地质调查局(USGS)颁布的三维地下水数值模型(MODFLOW),模拟不同湖底防渗措施和机井开采方案下龙湖周围地下水位变化以及龙湖入渗量,对龙湖周边布井方案可行性和降低地下水效果加以分析和比较。 相似文献
2.
藏南羊卓雍错流域主要湖泊水质状况及其评价 总被引:9,自引:0,他引:9
湖泊水质是研究湖泊变化及其对气候变化响应的重要指标.分析了藏南羊卓雍错流域主要湖泊的水化学指标概况、 水化学组成、 矿化度时空分布及其驱动, 并在此基础上对各湖泊的水质现状进行了评价. 研究表明: 流域内各湖泊水化学性质虽有一定的相似性, 但矿化度等水化学指标浓度存在显著差异, 各湖泊水化学组成亦差异显著. 羊卓雍错和巴纠错均为硫酸盐类-镁组, 沉错为硫酸盐类-钠组, 普莫雍错和空姆错则分别为重碳酸盐类-镁组和重碳酸盐类-钙组. 各湖泊矿化度差异较大的主要原因在于其补给来源不同, 以降水补给为主的湖泊矿化度远高于以冰雪融水补给为主的湖泊. 与全球气候变暖相对应, 各湖泊矿化度变化反映了气候变化的影响, 而水电站运行对羊卓雍错水体化学性质变化有所贡献. 目前, 羊卓雍错、 普莫雍错水质为劣V类, 空姆错、 沉错、 巴纠错水质为V类. 深入探讨该流域水质对气候变化的响应, 亟需更长时间序列的数据支持. 为此, 必须继续在该流域长期开展全方位的水化学观测与水质监测、 评价工作. 相似文献
3.
四川盆地西部侏罗纪为内陆盆地,除其北缘早侏罗世有湖沼相外,主要为河流相与湖泊相,邻龙门山区发育冲积扇,其余地区发育冲积平原相和泛滥平原相。依据湖泊积水状况,将湖泊相细分为时令湖相、间歇湖相和长年湖相。印支期,甘孜-阿坝造山带形成,四川盆地由湿热气候演变为干燥、炎热气候;并使早侏罗世-中侏罗世早期成为长年湖泊环境。受燕山早中期构造运动影响,河流相、时令湖相与间歇湖相发育。长年湖相形成了侏罗系重要的生储油层系。河流相的粗碎屑岩成为储层,时令湖相与间歇湖相的泥质岩成为盖层,组成了侏罗系中上统多个储盖组合。 相似文献
4.
利用ICESat-1和CryoSat-2测高数据获取了2003—2017年洞庭湖流域内湖泊的水位信息,分析了湖泊水位的时间变化过程,并结合TRMM卫星降水数据及人类用水等数据,讨论了湖泊水位变化对气候及人类活动的响应.结果表明,流域中80%的湖泊在2003—2009年呈现出水位下降趋势(-0.18~-0.09 m/a);75%的湖泊在2010—2017年呈现出水位稳定或上升趋势(0~0.39 m/a);总体来看,75%的湖泊在2003—2017年呈现出水位上升趋势(0.02~0.22 m/a).分析表明,湖泊水位变化为多种因素共同作用的结果,降水为近年来洞庭湖流域内湖泊水位变化的主要驱动因子;以三峡水库为代表的水库运行会对湖泊水位产生季节性影响;同时,人类用水的持续增长也对湖泊水位有一定的影响.多源测高卫星为长时序大范围的湖泊水位监测提供了有力的手段,这对研究湖泊水位变化及其与气候和环境的响应具有重要意义. 相似文献
5.
S. M. Jepsen C. I. Voss M. A. Walvoord J. R. Rose B. J. Minsley B. D. Smith 《Hydrogeology Journal》2013,21(1):185-200
Many lakes in northern high latitudes have undergone substantial changes in surface area over the last four decades, possibly as a result of climate warming. In the discontinuous permafrost of Yukon Flats, interior Alaska (USA), these changes have been non-uniform across adjacent watersheds, suggesting local controls on lake water budgets. Mechanisms that could explain the decreasing mass of one lake in Yukon Flats since the early 1980s, Twelvemile Lake, are identified via a scoping analysis that considers plausible changes in snowmelt mass and infiltration, permafrost distribution, and climate warming. Because predicted changes in evaporation (2 cmyr?1) are inadequate to explain the observed 17.5 cmyr?1 reduction in mass balance, other mechanisms are required. The most important potential mechanisms are found to involve: (1) changes in shallow, lateral groundwater flow to the lake possibly facilitated by vertical freeze-thaw migration of the permafrost table in gravel; (2) increased loss of lake water as downward groundwater flow through an open talik to a permeable subpermafrost flowpath; and (3) reduced snow meltwater inputs due to decreased snowpack mass and increased infiltration of snowmelt into, and subsequent evaporation from, fine-grained sediment mantling the permafrost-free lake basin. 相似文献
6.
7.
Inmaculada de Vicente Francisco Guerrero Francisco Jiménez-Gómez Luis Cruz-Pizarro 《Comptes Rendus Geoscience》2010,342(1):46-52
This study focuses on two Mediterranean oligotrophic high mountain lakes located in the Sierra Nevada National Park (southern Spain): Río Seco (RS) and La Caldera (LC). A combination of field measurements and laboratory experiments is used: (i) to quantify in situ settling fluxes; (ii) to study the soluble reactive phosphorus (SRP) release or uptake by settling and resuspended particles; and (iii) to discriminate between the biotic and abiotic contribution for such patterns. In general, all suspensions (lake water untreated and lake water enriched with settling and with resuspended matter) in both study lakes release significantly more SRP to the solution when biological activity was suppressed. Biological uptake from settling and resuspended matter is likely to be limited by the bacterial consumption of P. Despite of these similarities, this study has revealed notable differences in the effect of sediment resuspension on SRP dynamics in both study lakes, when simulating natural conditions (biotic and abiotic processes). While in LC, the enrichment of lake water with settling and with resuspended matter did not cause an increase in SRP concentrations in lake water, SRP concentrations in RS at the end of the experiment were significantly higher (probability P < 0.05) in lake water enriched with resuspended matter (3.2 μg/l) than in natural lake water (lower than the detection limit). Accordingly, it is reasonable to expect that sediment resuspension, which occurs more frequently in RS compared with LC, affects drastically the SRP availability in the water column in RS. 相似文献
8.
Cao Wenbing Wan Li Hu Fusheng Shen Zhaoli Department of Water Resources Environmental Engineering China University of Geosciences Beijing Yan Weide Qinghai Exploring Institute of Hydrogeology Engineering Geology Ledu 《中国地质大学学报(英文版)》2001,12(2)
TheZhalingandElinglakes,whichplayanimportantroleinadjustmentandstorageofwaterfortheupstreamareaoftheYel lowRiver,aretwoofthelargestnaturalfreshwaterlakesintheYellowRiverdrainagearea .Thewaterenvironmentofthetwolakesandtheiradjacentregionsisquiteunique.S… 相似文献
9.
Trend of Salt Lake Changes in the Background of Global Warming and Tactics for Adaptation to the Changes 总被引:5,自引:0,他引:5
ZHENG Mianping QI Wen JIANG Xianfeng ZHAO Yuanyi LI Minghui Open Laboratory of Saline Lake Resources Environment Chinese Academy ofGeological Sciences Beijing R & D Center for Saline Lakes Epithermal Deposits Chinese Academy of Geological Sciences Beijing 《《地质学报》英文版》2004,78(3):795-807
Salt lakes are a mirror of climatic changes and provide holographic records of environmental changes of lakes. According to a study of geological hazards in typical salt lake areas in China and other regions, the authors explain how geological hazards in salt lake areas are caused by natural agents and how humans can seek benefits, avoid hazards and reduce losses on the premise that they have monitored and mastered the trend of salt lake changes in advance and even can store flood and recharge water in lakes and extract saline resources. The climate 相似文献
10.
Mono Lake, a major closed-basin alkaline salt lake in eastern California, derives its water from a mixture of creeks and springs, with the former providing in excess of 75% of the total. The Li isotopic composition of lake water has not varied significantly over a 4 year meromictic period (δ7Li ∼ +19.5). Springs are isotopically distinct: groundwater springs and seeps carry water enriched in isotopically heavy Li whereas thermal springs supply isotopically light (δ7Li < lake), but 10 times more Li-rich, water. Isotopic fractionation during crystallization of carbonate tufa and evaporitic salt appears to be insignificant, and thus cannot be called on as a principal control of the isotopic balance of Li of the lake. Isotopic differences between the end-member source components permit a water budget to be calculated, suggesting (1) springs provide > 50% of the Li to the lake; (2) the Li budget is sensitively balanced on small thermal spring contributions, < 3% of the total spring inflow; and (3) the residence time of Li in the lake is 28 ka. Other Great Basin closed lakes have variable Li isotopic compositions (δ7Li from +16.7 to +23.7), all of which differ significantly from those of several major lakes and seawater (homogeneously ∼ +32). 相似文献
11.
L. A. Shevenell 《Environmental Geology》2000,39(7):807-815
Within the next 10–15 years, over 35 mines in Nevada will have a lake in their open pit mines after dewatering and cessation
of mining. Of the ten past or existing pit lakes at eight different gold mines for which temporal data are available, most
had near neutral pH, yet most had at least one constituent (e.g., As, SO4, TDS) that exceeded drinking water standards for at least one sampling event. Most samples from pit lakes had TDS exceeding
drinking water standards, but lower than that in the natural Pyramid (TDS≈5,500 mg/l) and Walker (TDS≈14,000 mg/l) Lakes.
In the past century, salinity increased in both natural, terminal lakes, in part due to irrigation withdrawals and evapoconcentration.
The salinity in the pit lakes may also increase through time via evapoconcentration. However, water balance models indicate
that up to 132% (Walker Lake) of the total yearly inflow evaporates from the terminal lakes, whereas steady-state may be reached
in the pit lakes modelled, where evaporative losses account for only ≈6% of the total pit lake volume annually and ≈100% of
the net inflow (groundwater inflow minus outflow, precipitation and runoff into the lake). The effects of evapoconcentration
are expected to be less significant at most pit lakes than at the natural, terminal lakes because (1) evaporation rates are
lower at many pit lakes because they are located at higher elevations than the terminal lakes, and (2) the surface area to
depth ratio of the pit lakes is >1000 times smaller than that of the terminal lakes.
Received: 1 March 1999 · Accepted: 13 April 1999 相似文献
12.
论成油和成煤的若干基本条件--以云南三个湖泊为例 总被引:1,自引:0,他引:1
本文以云南三个湖泊水生生物的数量和质量、沉积环境与有机质的关系、有机质埋藏初期和成岩早期的演化趋势等方面,着重讨论了成油和成煤的基本条件,并联系我国新生代成油成煤的有关条件,提出六点主要认识:1.成油、成煤必须具有构造条件;2.湖泊所处气候带必须适中;3.湖水须属富营养型;4.成煤与成油要求湖水深度不同;5.湖水的氧化还原状况;6.成煤还需没有陆源碎屑物质的补入。 相似文献
13.
武汉市位于长江中游,长江与汉江在此交汇,城区河网纵横,湖泊众多,素有"江城"和"百湖之市"之称.湖泊对于武汉城市的可持续发展及宜居城市建设有着特别重要的意义.关于武汉市的湖泊前人曾开展了大量的研究,但对于湖泊的成因则研究较少.湖泊的成因不仅对武汉市近代地质环境演化具有重要意义,同时也是湖泊保护的基础科学问题.在地质地貌调查上,通过江湖古地理演变分析,结合历史文献记录等综合研究,认为武汉湖泊的形成与河流地质作用过程密切相关,据此将武汉市湖泊的成因类型划分为:河道遗迹湖(又分河道废弃湖和河道洲滩夹湖)、河堤溃口湖、河间洼地湖和沟谷壅塞湖四种类型.分析了各类湖泊的特征、地貌分布及形成过程.其中沟谷壅塞湖是现存湖泊的主要类型,其形成演化与区域气候变化背景下的河海相互作用密切相关,分别经历了湖盆形成期(20~14 ka)、湖泊形成期(14~7 ka)和湖泊发展期(7 ka以来)3个阶段.此外,武汉的城市与湖泊经历了由"湖中城"到"城中湖"的发展历程,围湖造地是武汉市最重要人为改造自然工程,依湖泊类型的不同采取了不同的围湖发展方式,汉口地区以河间洼地湖为主,主要以"筑堤-排水-造地"填湖发展;武昌和汉阳地区以沟谷壅塞湖为主,采取的是"堵塞湖汊造地"的环湖发展方式.在未来的城市建设中,有计划地实施湖-湖连通和河-湖连通工程是十分必要的. 相似文献
14.
再论巴丹吉林沙漠湖泊水的补给来源、补给模式与高大沙山的形成机理 总被引:1,自引:0,他引:1
依据已有研究成果和最新调查资料, 在综述沙漠湖泊与高大沙山研究进展及存在问题的基础上, 深入探讨了巴丹吉林沙漠湖泊水的补给来源、补给模式及高大沙山的形成机理. 结果认为, 沙漠湖泊水和地下水的补给来源不是当地降水和周边雅布赖山-北大山的降水形成的地表洪水, 而是南部青藏高原(包括祁连山)现代大气降水、冰雪融水、高原湖水的远源补给. 补给模式为高原富含CO2气体和CaCO3的入渗水, 通过深大导水断裂通道形成的区域地下水流循环系统, 源源不断地自南向北运移到沙漠地带, 地下水在通过沙漠湖泊区弧形"叠瓦状"垂向导水构造断裂向上越流过程中被广泛分布的岩浆岩加热, 沿断层溢出地表形成湖泊群, 同时导致水中CO2的释放和CaCO3的沉积, 形成钙华体. 高大沙山的形成机理是深层地下热水向上越流补给了沙漠覆盖区, 在承压水头以下形成鼓丘状的沙漠地下水, 承压水头以上, 水蒸汽继续向上运移并被凝结在沙粒表面, 未被吸附凝结的热水蒸汽继续向上运移并被吸附在新沉积的沙粒表面, 形成湿砂层并接受更新的沙粒沉积, 如此反复循环, 则沙丘高度不断增加, 逐步形成高大的固定沙山. 相似文献
15.
Hydrological processes of adsorption,sedimentation, and infiltration into the lake bed during the 2004 urban flood in Dhaka city,Bangladesh 总被引:1,自引:1,他引:0
The urban flood of Dhaka city in September 2004 is a result of heavy rainfall (341 mm a day or more than 600 mm in 5 days).
In addition to the local rainfall, elevated water levels in the surrounding rivers may have affected the flood duration by
bank filtration. Two lakes, Banani and Gulshan, in the mid of the city are the part of general storm water retention system
in Dhaka. Flood water runs through the lakes acting as channels to the pumping station downstream. A tank model is used in
this study to describe the total drainage process with the hydraulic geometry and resistance laws to derive cross-sections
and friction factors of the quasi-uniform flows. Assuming the dissolved matters of the flood water was of similar composition
as in the lake sediments, the process was a combination of adsorption and sedimentation. Lake sediment samples collected in
March 2004 show an anomaly of chromium which may reflect the previous 1998 flood, and there may be a diffusive leakage from
the source area to the adjacent zones. Further evidence of infiltration process is seen in records of diurnal thermal stratification
of Lake Banani. It responds to only heavy rainfalls over 100 mm/day, and the fact means that infiltration to the groundwater
is rather intermittent. 相似文献
16.
地震诱发的堰塞湖初步研究 总被引:33,自引:3,他引:30
由于地震引发山体滑坡并堵塞河道形成的湖泊称为地震堰塞湖。据统计,我国自1856年以来,共计产生141个地震堰塞湖,按照其形成和造成的灾害来看,堰塞湖可以分为3类:高危型堰塞湖、稳态型堰塞湖和即生即消型堰塞湖。高危型堰塞湖由于蓄水量大、落差大,往往在形成后几天至几年后会被冲垮,形成严重的地震滞后次生水灾。稳态型堰塞湖(亦称“死湖”),可以存在很长时间且湖积水量很大。即生即消型堰塞湖为震时形成的短时堰塞湖,很快会被后来累积的水体冲毁,一般危害不大。如果简单的用时间来区分堰塞湖的类型,那么在一天或者几天内溃决的是即生即消型堰塞湖;几天至100年溃决的是高危型堰塞湖;溃决时间超过100年者,是稳态型堰塞湖。 相似文献
17.
内蒙古五原县塔尔湖地区发育一系列湖泊,与当地干旱气候形成鲜明的对比,湖泊成因机制对河套地区第四纪水文地质、气候环境研究具有重要意义。对色尔腾山山前—塔尔湖湖泊—黄河沿线不同水体样品进行水化学测试后,利用Gibbs模型投影显示湖泊采样点主要落在蒸发-浓缩端元和岩石风化端元的过渡带,而远离大气降水作用带,地下水更靠近岩石风化端元,说明湖泊接受地下水补给,蒸发强烈;Piper三线图显示山前泉水以HCO3—Ca型为主,河套平原地下水以HCO3—Na、Cl—Na型为主,黄河水为HCO3—Na型,湖泊以Cl—Na型为主,说明塔尔湖地区地下水与湖泊存在水力联系,HCO3—Na型地下水经过蒸发浓缩作用转变成了盐度更高的Cl—Na型湖泊,导致盐分的聚集;地下水可溶性固体总量(TDS)自北向南由262 mg/l快速增加至2 296 mg/l,而湖泊TDS先升后降,最后小于地下水TDS,最大值在塔尔湖地区北部,为1 213 mg/l,说明湖泊还受现代黄河补给,地下水TDS变化满足山前—盆地的水文地质模型。塔尔湖地区的湖泊既可以发育于古河床亚相也可以发育于堤坝亚相,且湖泊呈零星分布,与古河道形成的牛轭湖特征不吻合,从而基本排除湖泊为古黄河残留的可能;潜水面之上的河流相沉积物由于风蚀作用被切穿,导致地下水出露,补给湖泊,从而推断塔尔湖地区湖泊主要为风蚀湖。 相似文献
18.
自20世纪70年代初以来,采用无线电回波探测(RES)等技术,在南极冰盖发现了70多个冰下湖泊,最近,随着Vostok冰芯钻孔逼近Vostok湖面,对南极冰盖下伏湖泊的研究提上日程,Vostok湖因其面积大以及有距离湖面最近的钻孔,成为冰下湖群中被优选考虑的“靶子”湖泊,主要研究目标定位于古气候学,原始生命科学两方面,目前工作尚处于技术研制阶段,技术关键点在于研制先进的湖泊沉积物钻探技术,无污染和自动化湖水,湖芯取样技术等,技术上的高难度使得该计划成为一项系统工程。 相似文献
19.
Groundwater dominated lakes are an important feature of many landscapes. Their sediments are a particularly valuable source of paleoenvironmental information in semiarid regions where perennial lakes may otherwise be scarce. Where groundwater and lake composition are favorable, carbonate mineral precipitation, evaporative concentration of lake water, and microbial processes can combine to strongly deplete dissolved Ca relative to influent groundwaters. The authigenic carbonate flux (ACF) can then become limited by water column cation availability and thereby be coupled to groundwater inflow rates and aquifer recharge. Here we analyze sedimentary records from two marl-producing, groundwater-controlled lakes and demonstrate a link between one-dimensional ACF and the Palmer Drought Severity Index (PDSI), a measure of land surface wetness. In a restricted outflow lake with high-carbonate alkalinity, ACF is enhanced during historically wet climatic periods in response to increased aquifer recharge rates. ACF in this lake declines during droughts. A neighboring dilute lake with a high rate of groundwater outflow shows comparatively weak coupling between ACF and PDSI history. Ionic chemistry, carbonate mineral equilibria, and δ13C patterns of dissolved inorganic carbon show that the sensitivity of the ACF signal depends on the degree of evaporative evolution of lake water and the mineral saturation state of the water column under conditions of stratification and ice cover. 相似文献
20.
苏干湖盆地是嵌套在柴达木盆地中的一个封闭盆地,大、小苏干湖是盆地地表水和地下水的汇集中心,两湖相距20km,但大苏干湖为咸水湖、小苏干湖为淡水湖。文章通过氢、氧同位素分析盆地中大、小苏干湖湖水补给来源,解释了两湖虽近,但矿化度差别较大的原因。为解决敦煌盆地地下水资源短缺问题,政府部门计划从苏干湖盆地地下水的主要补给源——大哈尔腾河引水至党河当中,但湖水补给源的不同,导致引水对两湖影响不一。结果表明,大苏干湖湖水补给来源为大、小哈尔腾河上游4 800m以上冰雪融水补给,且径流路径长,蒸发强烈。小苏干湖主要由来自党河南山西段和阿尔金山区雨水补给,径流路径短。因此,大、小苏干湖矿化度差别较大,补给源的不同导致引水对大苏干湖湖水影响较大,而对小苏干湖湖水影响较小。 相似文献