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1.
新近系地下淡水是下辽河三角洲地区的盘锦市和辽河油田主要供水水源。地下水处于封闭到半封闭环境,包括明化镇组(Nm)和馆陶组(Ng)两个含水岩组。天然状态下,地下水位接近或高于地表;开采条件下,地下水位逐年下降,形成区域性降落漏斗,地下水流场均发生显著变化,形成汇向开采区的向心流场。开采明化镇组地下水为主的盘东水源地,开采初期水位下降速率为1.61~5.19m/a,至1996年降至0.63~1.03m/a;馆陶组地下水为主的各水源地,开采初期水位下降速率为2.10~4.21m/a,至1996年减至1.49~2.05m/a。这是由于地下水流场变化,导致明化镇成水体内侵和下移所致,该地地下水中Cl^-的不断增高也证明了这一点。至1998年。平面上,成水体每年增加3.18km^2,盘东水源南部,成水体内侵速率已达每年220m。垂向上成水体年下移速率一般每年0.5~1.67m。进行新近系地下水动态特征和演化趋势研究,将为合理开发利用宝贵的淡水资源提供科学依据。 相似文献
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在辽河三角洲地区,布设10个地下水监测点,通过3年的动态监测,得到第四系孔隙潜水水质动态变化规律.辽河三角洲地区地下水矿化度普遍较高,范围介于1~31 g/L.西部山前倾斜平原,地下水矿化度较小,水质较好.南部滨海低平原区,矿化度介于12~31 g/L,地下水为盐水.东北部冲积平原区地下水矿化度介于1~3 g/L,为微咸水.在地下水化学类型方面,HCO3-Na型地下水主要分布于西部山前倾斜平原区;Cl-Na型地下水主要分布在南部滨海低平原地区;Cl-Na·Ca型地下水主要分布在北部和东部的冲积平原区;HCO3·Cl-Na型地下水主要分布在东北部的冲积平原区.山前倾斜平原地区,地下水水质基本保持着良好的状态,大部分地区水质变化不大.南部低平原区,Cl-、SO42-、Na+及矿化度持续升高,高矿化度、氯化物型和钠型水分布面积增大,向周边扩散.北部冲积平原地区,地下水的各组分及矿化度略有起伏,变化不大并趋于稳定. 相似文献
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云应盆地东北部属鄂北贫水地区,赋存于古近系—第四系含水层中的地下水是当地生产、生活用水的主要来源,亟需查明含水层的结构、含水层间地下水的转化关系等基本条件,为研究区内合理开发利用地下水提供依据。本研究通过野外水文地质调查、水文地质钻探工作,将研究区划分为单层含水层与双层含水层结构两个亚区(6个小区)。并通过地下水水位动态长期监测,获取了区内不同含水层的水位动态变化特征,分析各含水层之间的水力联系,建立了区域地下水转化的概念模式,即:研究区地下水以接受山前降雨入渗及风化裂隙水侧向径流补给为主,主要以水平径流的形式经古近系孔隙-裂隙含水层及第四系孔隙承压含水层往澴水方向运移,而后进入第四系孔隙潜水含水层。地下水和地表水在不同季节补排模式不同,雨季地表水(澴水)补给地下水,旱季地下水向地表水(澴水)排泄。古近系孔隙-裂隙水与上覆第四系孔隙水联系密切互为补给,共同构成具有统一水力联系的垂向多层结构的含水系统。独特的含水层结构决定了区内地下水接受降水补给的条件较差,地下水可开采资源量总体较贫乏,建议重点利用区域地表水资源,适度开发地下水资源,推进农业节水灌溉工程,实现水资源可持续利用。 相似文献
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三江平原地下水资源潜力评价 总被引:6,自引:0,他引:6
三江平原地区第四系松散堆积物厚度一般为100~200m,最厚达:300m,为结构单一、大厚度的砂、砂砾石含水层,储存运移着巨量的孔隙水(部分为微承压水)。含水层疏导功能与富水性强,单井涌水量多在1000m^3/d,且水质为矿化度小于lg/L的淡水。依据含水层的地质时代和贮水介质类型,将三江平原地下水系统划分成第四系孔隙含水层亚系统、第三系孔隙裂隙含水层亚系统、基岩裂隙含水层亚系统。其中第四系孔隙含水层亚系统进一步分成更新统含水层次级亚系统和全新统含水层次级亚系统;第四系更新统含水层次级亚系统又细分为下、中、上更新统含水层。根据盆地浅部区域地下水分布的主要控制因素(流域水系、地质构造、地貌条件、含水层结构及地下水补、径、排条件),对三江盆地地下水系统进行了系统的描述;各地下水动力亚系统受外部动力条件(降水、蒸发、地表水、地下水)的制约,同时受内动力条件(含水介质循环条件)的控制,形成了独特的地下水动力场;论述了含水层系统的特征、边界条件、输入特征、输出特征、内部功能特征等。最后对三江平原的地下水资源潜力进行了计算与评价:依据水均衡原理,充分地考虑了计算区及计算单元在开采状态下多年补、排均衡的基础上,利用长系列的气象、水文资料,应用三维模型模拟计算了丰、平、枯水年各计算单元的地下水补给量和可开采量,进而求得了多年均衡条件下全区地下水可开采资源量。 相似文献
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以控制地面沉降为约束的地下水资源评价——以上海地区为例 总被引:2,自引:0,他引:2
以上海市区第V承压含水层(埋深约350m )以上的整个第四系松散沉积层为研究体,将上海地下水系统作为一个完整且不可分割的系统来研究。由于开采地下水资源引起地下水系统内部物质能量变化,因而产生一系列的环境地质问题(如地面沉降、地下水位下降、资源开采条件恶化等)。根据研究区地下水系统特征和已有的研究程度,在技术方法和途径上,着重研究上海地区第四系含水层结构、水文地质工程地质条件,建立水文地质工程地质概念模型; 在此基础上建立以地下水资源开采量最大、水位降幅及地面沉降较小、社会经济效益较好为目标的地下水拟三维渗流一维地面沉降的评价与管理模型,并为我国大中城市(特别是在诸如开采地下水引起的地面沉降问题的地区)的地下水资源评价与管理提供可借鉴的经验和方法。 相似文献
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北京西山地区地下水资源丰富,水质优良,是北京市重要的地下水供水水源地之一。长期过量开采地下水已经引起了区域地下水水位下降等环境问题。南水北调客水进京后,将会改变区域用水结构,逐步实现对含水层系统的涵养目的。采用有限差分方法进行区域含水层系统数值模拟,分析不同开采条件下含水层系统响应特征。取得如下认识:西山地区地下水开采总量达到3.546 2×108m3/a,为达到可持续开采目的,需要将开采量压至2.798 8×108m3/a,实现采补平衡;维持现状开采至2030年,岩溶水水位下降22m,第四系承压水水位下降约28m,部分地区第四系潜水含水层出现疏干现象;南水北调进京后,按照规划压采方案实施,2030年末岩溶水水位平均恢复约5m,第四系承压水水位下降约6m。区域岩溶含水层恢复贮水0.185 4×108m3,第四系含水层系统贮水损失2.782 8×108m3。 相似文献
7.
《吉林大学学报(地球科学版)》2015,(Z1)
<正>研究区位于渤海湾盆地辽河坳陷西部凹陷南段,总面积约700 km2。从下到上发育古近系沙河街组、东营组,新近系馆陶组、明化镇组和第四系。在沙河街组的致密砂岩中发现了工业气流,双202井日产气2.5×104 m3。在中国其他盆地致密砂岩气储层中地层水矿化度一般较高,水型为Ca Cl2型[1];但研究区沙河街组的地层水矿化度较低,水型以Na HCO3为主。地层水的特征是盆地内水-盐反应的综合体现。因此,致 相似文献
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吉林省乾安县位于松嫩低平原中央凹陷带,受继承性沉降运动影响,白垩纪晚期以后,在断裂构造的基底上沉积了新近系的弱胶结地层和第四系松散堆积物,为地下水赋存提供了有利条件.全县主要取水水源为地下水,局部地区(县中心)地下水受集中开采影响,形成地下水位降落漏斗,导致地下水质受到污染.为进一步查明该区地下水赋存,分布以及水质变化规律,本文对该区水文地质特征进行全面分析,进而对地下水资源进行了评价,研究结果可为地下水合理开发利用提供依据. 相似文献
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新疆渭干河-库车河三角洲绿洲地下水特征对天然植被的影响分析 总被引:1,自引:0,他引:1
依据实际观测资料和前人研究成果,对渭干河-库车河三角洲绿洲地下水特征对天然植被的影响进行分析.结果表明:受农业生产活动影响,研究区近10a间地下水位及水质发生了明显变化,地下水位约下降了1m左右,地下水矿化度平均降低0.54g·L-1,地下水变淡与地下水水位下降有着较好的相关性.由于地下水埋深较浅,渭干河-库车河冲积扇下部荒漠区矿化度较大,地表积盐,地下水水质成为天然植被的限制因素.由于防治土壤盐渍化,灌溉排泻地下水,在绿洲区大量开采利用地下水,以及河水对地下水补给不断减少等原因,造成三角洲下部绿洲外围荒漠区的地下水位逐渐下降,致使绿洲周边天然灌丛及草本植物的衰退. 相似文献
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Growing demand for potable water for various needs has lead to indiscriminate exploitation of groundwater resources, particularly,
in the terrain where surface water resources are negligible. One such area is an island where groundwater is the only source
of fresh water. Groundwater is the prime source of fresh water on most of the atolls in the world. Groundwater on these islands
is in the form of thin fragile floating lens and is often vulnerable to overexploitation, draught, tidal waves, tsunami and
cyclone resulting in seawater ingress. Sustainable development of this meager source of fresh groundwater for a longer time
becomes a more difficult task on small atolls with a large population depending on this vital resource. To develop a sustainable
management scheme and identify the vulnerable part of aquifer, characterization of the aquifer system on islands is imperative.
Groundwater on an atoll is extremely vulnerable to seawater mixing through natural as well as human activities. One such natural
process is the tides of the ocean. The response of sea tide to the water table on the island offers valuable data as well
as cost-effective means to characterize an aquifer system. Such characterization is vital for the management of groundwater
resources on an atoll. The obtained results have compared well with the parameters obtained through a conventional pumping
test. Therefore, the use of tidal response to the water table, which can easily be recorded, provides a rapid and cost-effective
means to characterization of the aquifer system on the island. 相似文献
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研究区位于潮白河冲洪积扇中上部,第四系松散孔隙含水层颗粒粗大,易接受补给,地下水固有防污性能处于差和较差,地下水水质整体良好。采用数值模拟方法,建立了三维地下水流数值模型,对孔隙度、弥散系数进行了率定,利用GMS中的MT3DMS模块建立了溶质运移模型。选取COD作为模拟指标,根据模型对水厂投产30年后两种不同情景方案下地下水水质状况进行了预测分析。结果显示,在正常工况和处理流程出现故障两种条件下,再生水厂对周围地下水环境有一定程度影响,但重点研究区内地下水模拟浓度远小于《地下水质量标准》中Ⅲ类水标准,污染物浓度虽低,影响距离却很远,因此要建立覆盖全厂区的地下水长期监控系统,避免污染事故。 相似文献
16.
Evolution of the groundwater environment under a long-term exploitation in the coastal area near Zhanjiang, China 总被引:3,自引:0,他引:3
Aquifers consisting of unconsolidated sediments in the coastal area near Zhanjiang in southern China are grouped into the
shallow, middle-deep and deep aquifer systems. Groundwater exploitation began in the 1950s in this district and has increased
from year to year since 1980. Measurements of groundwater levels and monitoring data of groundwater chemistry at some 60 wells
since 1981 are examined to analyze the evolution of hydrodynamics and hydrochemistry in the coastal aquifers. The results
indicate that groundwater levels in the middle-deep and deep aquifer systems have fallen continuously and the extents of the
depression cones in water levels have increased in the past two decades, even though the water levels recovered to some degree
during the period of 1997–2001. In 2004, the lowest water levels in the middle-deep and deep aquifer systems were 23.58 and
21.84 m below sea level, respectively. The groundwater has TDS ranging from 40 to 550 mg/L, and is of low pH, commonly varies
between 4 and 7. Concentrations of total iron and manganese exceed the concentration limits of the drinking water standards.
The hardness is in the range of 10–250 mg/L. Chloride contents of the groundwater range from 10 to 60 mg/L. The chloride and
TDS do not show systematically increasing trends. Although the water levels in the exploitation center near the coast are
significantly lower than the sea level and the depression cones of water levels in the middle-deep and deep aquifer systems
have expanded to the sea, sea water intrusion has not been observed until recently. This phenomenon is quite unique in the
coastal area near Zhanjiang. 相似文献
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Groundwater, as a precious resource hidden underground, is an important component of the global water system. Transboundary
aquifers containing substantial amount of groundwater often carry crucial ecological and social implications. Yet, it is unfortunate
that transboundary aquifers have hardly been in the forefront of political and scientific discussions, and have not received
due attention by policymakers. This article attempts to summarize the investigation on the eight transboundary aquifers that
China shares with the neighboring countries. An overview on the groundwater resources in China, including its distribution,
exploitation and challenges is also provided. Hydrogeological condition of the Heilongjiang-Amur River Basin aquifer, which
is one of the eight major aquifers, is further elaborated. Cooperative activities carried out by China and Russia on monitoring
and management of this aquifer are also presented. 相似文献
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Medhat A. El-Bihery 《Environmental Geology》2009,58(5):1095-1105
Recently, Ras Sudr (the delta of Wadi Sudr) area received a great amount of attention due to different development expansion
activities directed towards this area. Although Quaternary aquifer is the most prospective aquifer in Ras Sudr area, it has
not yet completely evaluated. The present work deals with the simulation of the Quaternary groundwater system using a three-dimensional
groundwater flow model. MODFLOW code was applied for designing the model of the Ras Sudr area. This is to recognize the groundwater
potential as well as exploitation plan of the most prospective aquifer in the area. The objectives were to determine the hydraulic
parameters of the Quaternary aquifer, to estimate the recharge amount to the aquifer, and to determine the hydrochemistry
of groundwater in the aquifer. During this work, available data has been collected and some field investigation has been carried
out. Groundwater flow model has been simulated using pilot points’ method. SEAWAT has been also applied to simulate the variable-density
flow and sea water intrusion from the west. It can be concluded that: (1) the direction of groundwater flow is from the east
to the west, (2) the aquifer system attains a small range of log-transformed hydraulic conductivity. It ranges between 3.05
and 3.35 m/day, (3) groundwater would be exploited by about 6.4 × 106 m3/year, (4) the estimated recharge accounts for 3 × 106 m3/year, (5) an estimated subsurface flow from the east accounts for 2.7 × 106 m3/year, (6) the increase of total dissolved solids (TDS) most likely due to dilution of salts along the movement way of groundwater
from recharge area to discharge area in addition to a contribution of sea water intrusion from the west. Moreover, it is worth
to note that a part of TDS increase might be through up coning from underlying more saline Miocene sediments. It is recommended
that: (1) any plan for increasing groundwater abstraction is unaffordable, (2) reliable estimates of groundwater abstraction
should be done and (3) automatic well control system should be made. 相似文献
19.
Ramasamy Jayakumar 《地下水科学与工程》2015,3(4):295-305
The paper illustrates the concept, methodology, essential components and importance of groundwater level monitoring in terms of various aquifers such as multiple aquifer, karst aquifer and other aquifers. The groundwater resources in Mekong countries including Cambodia, Laos PDR, Myanmar, Thailand and Vietnam have also been reviewed. Finally, the author briefly presents Global Groundwater Monitoring Network 相似文献