共查询到18条相似文献，搜索用时 109 毫秒
1.
河北平原地下水14C年龄新认识 总被引：4，自引：0，他引：4
本文对河北平原第四系地下水14C年龄最新的结果进行了分析,得出如下认识:(1)垂向上,地下水的14C年龄随深度的增加而增大,或者沿地下水的流向而增大。但是,在同一孔组中,地下水埋深大于300m时出现了混乱现象。地下水14C年龄不但不增大,反而减小,其原因复杂;(2)水平方向上,第三含水组Q2地下水较老的年龄出现在河北平原中部,大致与子牙河方向一致,而第四含水组Q1地下水较老的年龄则呈北东东方向展布,即沧州—歧口一线分布,可能是地质结构影响所致。 相似文献
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河北平原地下水氢,氧,碳,氯同位素组成的环境意义 总被引：4，自引：3，他引：4
地下水是古气候信息的载体，它的化学成分和同位素组成可以反映古气候的演变。应用＾３Ｈ、＾１４Ｃ和＾３６Ｃｌ资料计算的河北平原地下水的年龄加下：第１含水组（Ｑ４）０－３ｋａ，第２含水组（Ｑ３）３－１００ｋａ，第３含水组（Ｑ２）１００－３００ｋａ，第４含水组（Ｑ１）３００－７００ｋａ，根据δ＾１８Ｏ和δＤ计算的地下水补给期的地面平均气温表明，第四纪以来河北平原气候环境是逐渐变暖的。根据第４至第１含水组（ 相似文献
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河北平原京津以南深层地下水资源形成规律的研究 总被引：1，自引：0，他引：1
本文应用同位素技术，结合含水岩组水文地质结构特征的分析及地下水动力方法的年龄计算，揭示了河北平原京津以南地区深层地下水的形成规律，得出深 地下水资源补给能力及承受开采能力很低的结论，这为今后深 地下不资源的合理开发利用提供了重要依据。 相似文献
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介绍了加速器质谱计测定＾３６Ｃｌ的原理和方法以及应用前景,并对沧州地区第四纪地下水的＾３６Ｃｌ进行了测定,利用氯同位素确定了沧州地区的咸水成因,同时根据＾３６Ｃｌ资料计算出该区第四系第三含水组地下水的年龄为２５０ｋａ,第四含水组地下水年龄为３００ｋａ。 相似文献
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河北沧州地区天然水的氯同位素组成 总被引：3，自引：1，他引：3
利用加速器质谱仪和高精度热离子质谱仪对沧州地区地下水的宇宙成因核素３６Ｃｌ以及稳定同位素３７Ｃｌ／３５Ｃｌ进行了测试，并利用氯同位素有效地确定了沧州地区咸水成因．同时，根据３６Ｃｌ资料计算出该区第四纪第三含水组（Ｑ２）地下水３６Ｃｌ年龄为２５０ｋａ，第四含水组（Ｑ１）地下水３６Ｃｌ年龄为３００ｋａ． 相似文献
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河北平原第四系地下水^36Cl年龄研究 总被引：6，自引：3，他引：6
本文报道了河北平原第四系地下水~(36)Cl研究的样品采集、制备,加速器质谱计(AMS)测定及地下水~(36)Cl年龄的计算原理和结果。 相似文献
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河北平原地下水动力环境演化影响因素的关联度分析 总被引：7，自引：0，他引：7
本文以河北平原典型地区-石家庄、衡水、沧州地区为例,采用灰色关联度分析方法,分析了地下水动力环境演化的影响因素。结果表明,对于第一含水组地下水,水动力环境演化主要受气象因素控制,对于第三含水组及漏斗区地下水,人为开采是最直接的影响因素。 相似文献
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河北平原地下水氢、氧、碳、氯同位素组成的环境意义 总被引：15，自引：0，他引：15
地下水是古气候信息的载体，它的化学成分和同位素组成可以反映古气候的演变。应用３Ｈ、１４Ｃ和３６Ｃｌ资料计算的河北平原地下水的年龄如下：第１含水组（Ｑ４）０～３ｋａ，第２含水组（Ｑ３）３～１００ｋａ，第３含水组（Ｑ２）１００～３００ｋａ，第４含水组（Ｑ１）３００～７００ｋａ。根据δ１８Ｏ和δＤ计算的地下水补给期的地面平均气温表明，第四纪以来河北平原气候环境是逐渐变暖的。根据第４至第１含水组（Ｑ１～Ｑ４）地下水δＤ＝－７０‰的等值线变化，认为第四纪以来，渤海海岸线逐渐由东向西移动。 相似文献
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利用在北京昌平地区采集的地下水样品的同位素和水化学特征,对昌平地区的地下水补给特征进行了分析。通过对样品的分组和讨论认为:第三组样品为当地大气降水垂向入渗水体的特征;第一组样品为下覆基岩向上覆第四系含水层的顶托补给,这股基岩水可能出自碳酸盐岩含水层;第二组样品存在几种可能的补给特征;第四组样品中3件为大气降水垂直入渗补给,另1件为混合样品。研究表明,昌平地区第四系含水层地下水分布及其补给方式情况各异,实际上说明了半干旱地区山前倾斜平原地区地下水分布的复杂性。 相似文献
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Corrected groundwater 14C ages from the carbonate aquifer in Yucca Flat at the former Nevada Test Site (now the Nevada National Security Site), USA, were evaluated by comparing temporal variations of groundwater 36Cl/Cl estimated with these 14C ages with published records of meteoric 36Cl/Cl variations preserved in packrat middens (piles of plant fragments, fecal matter and urine). Good agreement between these records indicates that the groundwater 14C ages are reasonable and that 14C is moving with chloride without sorbing to the carbonate rock matrix or fracture coatings, despite opposing evidence from laboratory experiments. The groundwater 14C ages are consistent with other hydrologic evidence that indicates significant basin infiltration ceased 8,000 to 10,000 years ago, and that recharge to the carbonate aquifer is from paleowater draining through overlying tuff confining units along major faults. This interpretation is supported by the relative age differences as well as hydraulic head differences between the alluvial and volcanic aquifers and the carbonate aquifer. The carbonate aquifer 14C ages suggest that groundwater velocities throughout much of Yucca Flat are about 2 m/yr, consistent with the long-held conceptual model that blocking ridges of low-permeability rock hydrologically isolate the carbonate aquifer in Yucca Flat from the outlying regional carbonate flow system. 相似文献
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Usama A. Abu Risha 《Hydrogeology Journal》2016,24(4):987-1000
The use of 14C (half-life?=?5,730 years) in modeling the evolution of the 36Cl/Cl ratios in groundwater is reported for the first time. The complexity of the Cl–36Cl system due to the occurrence of different Cl and 36Cl sources and the difficulty of the determination of the initial groundwater 36Cl/Cl ratios have raised concerns about the reliability of using 36Cl (half-life?=?301 thousand years, a) as a groundwater-dating tool. This work uses groundwater 14C age as a calibrating parameter of the Cl–36Cl/Cl decay-mixing models of three wells from the southwestern Great Artesian Basin (GAB), Australia. It aims to allow for the different sources of Cl and 36Cl in the southwestern GAB aquifer. The results show that the initial Cl concentrations range from 245 to 320 mg/l and stable Cl is added to groundwater along flowpaths at rates ranging from 1.4 to 3.5 mg/l/ka. The 36Cl content of the groundwater is assumed to be completely of atmospheric origin. The samples have different Cl–36Cl/Cl mixing-decay models reflecting recharge under different conditions as well as the heterogeneity of the aquifer. 相似文献
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大型新生代断陷盆地的浅层地下水的脆弱性评价——以山西太原盆地为例 总被引：3，自引：1，他引：2
为开展山西太原盆地的地下水环境保护工作,在GIS平台上利用DRASTIC模型采用地下水位埋深、含水层净补给量、含水层介质、土壤介质、地形、包气带、水力传导系数7个指标评价了盆地浅层孔隙地下水的脆弱性.结果表明:太原市与介休市是盆地内地下水脆弱性最高的地区,同时也是山西省工农业最发达的地区.为解决工农业发展带来的高污染风险性与地下水环境脆弱性这一对明显的矛盾,应加强以上地区的地下水污染防治工作,在开展工作时应坚持"以预防为主,防、治结合"的原则. 相似文献
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Identifying the recharge sources and age of groundwater in the Songnen Plain (Northeast China) using environmental isotopes 总被引：5，自引：0，他引：5
The recharge sources and groundwater age in the Songnen Plain, Northeast China, were confirmed using environmental isotopes. The isotopic signatures of the unconfined aquifers in the southeast elevated plain and the north and west piedmont, cluster along local meteoric water lines (LMWLs) with a slope of about 5. The signature of source water was obtained by the intersection of these LMWLs with the regional meteoric water line (RMWL). This finding provides evidence that the recharge water for these areas originate from the Changbai Mountains and the Low and High Hingan Mountains, respectively. Groundwater in the unconfined aquifer in the low plain yields a LMWL with a slope of 4.4; its nitrate concentration indicates the admixture of irrigation return flow. The δ-values of the unconfined aquifer in the east elevated plain plot along the RMWL, reflecting recharge by local precipitation. The mean residence time of groundwater in these aquifers is less than 50?years. However, the 14C age of the groundwater in the confined Quaternary aquifer ranges from modern to 19,500?years, and in the Tertiary confined aquifer from 3,100 to 24,900?years. Modern groundwater is mainly recharged to the Quaternary confined aquifer on the piedmont by local precipitation and lateral subsurface flow. 相似文献
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Assessment of the Capoterra coastal plain (southern Sardinia, Italy) by means of hydrogeological and geophysical studies 总被引：1，自引：0，他引：1
Hydrogeological and geophysical surveys confirm that the aquifers of the Capoterra plain in Sardinia (Italy) constitute a complex, multilayer system. In the north-east of the plain, this system is composed of a shallow aquifer of recent alluvium and a deeper aquifer separated from the former by a clay layer; in the south-west there is no separation between the two aquifers. The deepest and most important member of the multilayer aquifer system is situated at the transition from Quaternary to Miocene sediments. With respect to deep structures and stratigraphy, several differentiations inside the Miocene sedimentary filling, whose overall thickness is in the order of 300 m, have been found. The combined interpretation of several datasets allows the Capoterra plain to be reliably modelled from surface to a depth of several hundreds of metres and provides the possibility of finding deeper groundwater resources. Concerning the latter, since Miocene materials are known to be impermeable in the middle of the plain, in contrast to the aquifers hosted in the Quaternary sediments and alluvium, the probability of finding fresh water at a depth of less than 350–400 m is very low. The condition of seawater intrusion affecting the aquifers is also elucidated. 相似文献
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Stable chlorine isotopic signatures and fractionation mechanism of groundwater in Anyang,China 
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下载免费PDF全文 Xiao-xia Tong Rong Gan Shu-qian Gu Xing-le Sun Kai-tuo Huang Xiao-feng Yan 《地下水科学与工程》2022,10(4):393-404
The present work provides an online Bench II-IRMS technique for the measurement of stable chlorine isotope ratio, which is used to measure the δ37Cl of 38 groundwater samples from the Karst and Quaternary aquifers in Anyang area. The regional distribution and signature of δ37Cl value are characterized on the base of isotopic data. The results suggest that the δ37Cl value of Quaternary groundwater decreases with increasing Cl? concentration, and has no correlation with δ18O and δD values, but closely correlates with the depth to water table. The fractionation mechanism of the chlorine isotope is expounded according to the type of groundwater. The δ37Cl value of karst water is generally positive, which is relevant to the dissolution of evaporite (gypsum mine), and may be caused by the mixing of groundwater and precipitation. The groundwater of Quaternary unconfined aquifer is mainly recharged by precipitation, and the δ37Cl value of groundwater is generally negative. The δ37Cl value of groundwater in Quaternary confined aquifer is more negative with increasing the depth to water level and elevated Cl? concentration, which is possible to result from the isotope fractionation of ion filtration. The groundwater with inorganic pollutants in Quaternary unconfined aquifer has generally a positive δ37Cl value. 相似文献
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The Role of Groundwater Leakage through Deep Wells for the Deformation of Groundwater Flow: a Case Study in Cangzhou Area 下载免费PDF全文
下载免费PDF全文 Overexploitation of groundwater in Cangzhou area has attracted wide attention. Different layers of the aquifer may be connected through wells, since most wells of the deep aquifer have screens in several layers. This study proved the existence of vertical flow through wells, calculated the flow velocity and quantity of vertical flow in wells with methods of both field measurement and numerical simulation. Further, the recharge of deep groundwater by vertical flow through wells was estimated. An annual recharge of 1.5×108-2.8×108m3 from the third aquifer to the forth aquifer in Cangzhou area was estimated, according to the in-well measurement by heat pulse flowmeter sonde. 相似文献
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山东省泰安市城区-旧县岩溶水系统地下水资源潜力评价 总被引：1，自引：1，他引：0
山东省泰安市城区-旧县岩溶水系统位于山东省中部的泰山南麓,为单斜构造式岩溶含水系统,由城区和旧县两个水源地组成,地势总体北高南低,面积约112 km2。含水系统内地层以新生界第四系和古生界寒武、奥陶系为主,此外,在南部和北部分布有较大面积的太古界泰山岩群火成岩。本区在构造单元上属鲁西台背斜的一部分,泰莱断陷盆地之西半部。区内断裂构造发育,主要有NE向的泰山断裂、徂徕山断裂及结庄断裂,NW向的洪沟断裂、滂河断裂、岱道庵断裂。含水系统包括第四系松散岩类孔隙含水岩组和寒武-奥陶系碳酸盐岩类裂隙岩溶含水岩组,地下水动态受降水及人工开采影响明显。截止2012年底,地下水日均开采量为5.2万m3,接近系统允许开采量5.79万m3,处于采补平衡状态。本文在充分利用前人研究资料的基础上,通过对牟汶河修建拦河坝,河水位抬高引起的岩溶水补给条件变化的研究,确定该含水系统尚具有开采潜力,其潜力主要来源于地表水入渗补给。通过研究计算,目前该含水系统还具有约2万m3/d的开采潜力。 相似文献