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1.
黑河流域水循环过程中地下水同位素特征及补给效应   总被引:24,自引:2,他引:24  
通过环境同位素及其Tamers、IAEA模型应用研究表明,黑河流域水循环过程中地下水同位素特征与补给源属性和数量密切相关,具有非均一性;东部以山区降水通过出山地表径流补给为主,西部冰川雪融水和山区基岩裂隙水是主要补给源,下游区依赖中游区河水下泄状况,蒸发特征明显。东部同位素较新且地下水更新较快,西部同位素较老且地下水更新较慢;祁连山前戈壁带地下水同位素与山区河水相近,细土平原带地下水补给河水;高台一带受酒泉低氚值地下水补给影响而河水和地下水氚值都偏低;近河道带地下水年龄较新,远离河道则较老。因此,充分利用地下水与地表水之间转化规律,联合优化调控,有利于该区地下水资源可持续利用。  相似文献   

2.
甘肃西部平原区地下水同位素特征及更新性   总被引:8,自引:4,他引:8  
大量同位素资料研究表明,甘肃西部黑河流域南部平原区地下水补给和更新的特征是,具有非均一性和有限性;潜水较年轻又更新快,承压水较老又更新慢;东部地下水更新较快,西部更新较慢;祁连山前戈壁带地下水更新较快,细土平原更新较慢;近河道带地下水更新速率大,远离河道则小。上述特征与出山地表径流量及其补给源属性密切相关。因此,结合地下水更新特征,充分利用祁连山前戈壁带较强的入渗条件和调蓄功能,与地表水联合优化调控,有利于该区水资源可持续利用。  相似文献   

3.
刘君  王莹  卫文  张琳  刘福亮 《水文》2017,37(1):51-55
为研究近几十年来佘太盆地地下水补给变化情况,通过现场调查分析,对佘太盆地浅层地下水开展同位素样品采集工作,并测定了其氢、氧稳定同位素的值。在分析同位素分布特征及变化规律的基础上,结合当地地质及水文地质条件识别了地下水补给来源和补给区并构建了浅层地下水的补给模式图,探讨了区域上浅层地下水的补给流动状况。通过分析研究区大气降水和地下水中的氢氧稳定同位素的变化特征发现:当地大气降水并不是地下水的主要补给来源,其补给源区为周边山区,补给来源主要是周边山区的大气降水,且地下水所经历的蒸发作用较明显;盆地的东、西部地下水的补给源区不尽相同,西部的补给区高程要高于东部的补给区高程,但两部分地下水所经历的蒸发强度基本相同。  相似文献   

4.
应用水文学方法推求河道渗漏补给量   总被引:1,自引:0,他引:1  
河北西部山区的河川在流经东部平原河道时。产生沿程损失,並不断地向地下水补给。计算这部分河道渗漏补给量,是进行平原区地下水资源中确定综合补给量的一项主要内容。河道渗漏补给量的现行计算方法,主要有地下水动力学方法和经验公式法,都离不开对有关水文地质参数的确定,在缺乏观测和实验的地区。方法的使用是困难的。本文推荐的水文学方法,是从分析河道输水过程中的入渗规律入手,完全利用已有的平原河道的水文观测资料’先用统计相关法求出单位河长输水损失量的经验公式,再用初损一后渗法求出损失量补给系数,最后又按河床质和河道流经地区的土壤岩性分类,给出分类的损失量公式和补给系数,解决了河道渗漏补给量的计算问题。  相似文献   

5.
利用稳定同位素识别黑河流域地上水的补给来源   总被引:7,自引:0,他引:7  
本文利用稳定同位素(2H和18O)及水化学方法识别黑河流域地下水的补给来源,估算黑河水与地下水的转化数量。研究结果表明,黑河流域地下水的主要补给来自山区出山河流,山前戈壁带是地下水快速补给区,中下游盆地地下水补给来源为引河灌溉和河流侧渗。黑河干流出山河水在张掖以上河段约4.4×108m3/a渗漏补给地下水,约占出山迳流量的27%。张掖—正义峡河段道地下水向河道平均排泄量为11.4×108m3/a,占该段河流迳流量的69%。研究成果不仅对黑河流域地下水的开发管理有着重要意义,对我国西北类似的内陆盆地地下水的开发管理有着借鉴意义。  相似文献   

6.
以柴达木盆地的诺木洪为研究区,利用氚与14C方法计算了当地各水体的年龄,分析地下水年龄分布特征及其可更新能力。结果表明:山区至冲洪积扇中部地下水年龄为15~18 a,为1952年之后补给的现代水,更新能力较强;冲洪积扇前缘地下水年龄不超过2 ka,具有现代水与古水混合的特征,更新能力较差;溢出带到盆地中心地下水年龄急剧变老,变化范围为5~28 ka,据此推测研究区溢出带位置的隐伏断层具阻水性质,该位置的地下水基本无更新能力。  相似文献   

7.
鲁北平原地下水同位素年龄及可更新能力评价   总被引:9,自引:2,他引:7       下载免费PDF全文
笔者采用大量的地下水环境同位素数据, 利用天然放射性氚和14C的通用测年技术, 分别估算浅、深层地下水的形成年龄, 评价地下水的可更新能力。研究结果表明, 鲁北平原浅层地下水的主要补给来自当地的大气降水和引黄河灌溉水, 循环速度较快, 循环时间20~50 a, 更新能力较强。深层地下水主要起源于古代大气降水, 是在比现在寒冷的气候条件下由大气降水入渗形成, 循环速度较慢, 循环时间8~20 ka, 更新能力较弱。  相似文献   

8.
河南平原浅层地下水年龄   总被引:1,自引:0,他引:1  
利用3 H法和CFCs法对河南平原第四系浅层地下水年龄进行计算,为河南平原浅层地下水可更新能力评价和水循环的研究提供依据。结果表明:2种方法计算出的年龄拟合误差较小(2a),均可代表河南平原浅层地下水年龄。总体上,河南平原浅层地下水主要为近50a以来补给的现代水。太行山、伏牛山、大别山山前地区以及开封西部的黄河两岸等地区浅层地下水年龄均小于30a,并且顺着地下水流向年龄逐渐增大。从山前地区和黄河两岸至平原区,浅层地下水开采潜力逐渐减小。总体上:平原北部地下水系统地下水年龄较小,地下水循环交替较快;平原南部地下水系统次之;平原中部地下水系统地下水年龄最大,地下水循环交替最慢。  相似文献   

9.
包气带在干旱半干旱地区地下水补给研究中的应用   总被引:3,自引:0,他引:3  
在干旱半干旱地区,包气带的溶质和同位素剖面不但可以提供较长时间尺度上的地下水补给信息,而且记录了过去气候变化与环境变化信息。本文基于学科组近10年的研究成果,以鄂尔多斯盆地为例(包括南部的黄土高原和北部的沙漠高原),将包气带和饱和带结合起来,利用多种环境示踪技术,提升了包气带在干旱半干旱地区地下水研究中的潜力,并将其应用到地下水补给历史重建、地下水补给机制确定、植被变化对地下水补给影响评价和地下水污染物全过程示踪中。研究表明,由于在干旱半干旱地区,包气带较厚且补给量有限,地下水和现今的浅表水文过程未达到水力平衡,如在沙漠高原西部,近2 500 a降水尚储存在包气带13 m以浅,地下水是4 000 a以前补给的,其水化学特征与浅部包气带水差异巨大;而在黄土高原,补给量较大,但包气带巨厚,年降水仍需要几十到上百年时间入渗到地下水(但并不意味着没有补给,其土壤水在包气带中平均入渗速率为0.1~0.3 m·a-1),包气带浅部溶质含量较深部和地下水中的高;典型黄土塬区的地下水均不含氚,地下水年龄在几百到上万年。黄土内部层状均匀的土壤质地特征和相对较老的地下水年龄揭示的均匀活塞流入渗是黄土塬区浅层地下水补给的主要方式。黄土高原退耕还林还草和沙漠区植被恢复导致地下水补给呈现不同程度的减少,反映在包气带上表现为溶质含量的增加,可用于定量化确定地下水补给量的变化。本文强化了包气带在干旱半干旱地区地下水补给研究中的作用,在未来地下水资源评价、地下水污染全过程刻画中应得到重视。  相似文献   

10.
甘肃省地下水资源及其开发利用状况研究   总被引:1,自引:0,他引:1  
赵建中  白福 《地下水》2010,32(6):65-67
甘肃省地处我国西北内陆,地下水资源匮乏,水资源供需矛盾突出,查明地下水资源大账显得十分必要。本文在全面收集和分析以往不同时期水文地质勘查及研究成果基础上,按不同水文地质单元、行政区划、地貌单元较系统地总结了各区地下水资源量,简要分析了开发利用状况。结果表明,甘肃省地下水天然补给资源量132.79×108m^3/a。其中,内陆河流域51.80×108m^3/a,黄河流域47.07×108m^3/a,长江流域33.91×108m^3/a;西部地区57.86×108m^3/a,东部地区20.97×108m^3/a,南部地区53.95×108m^3/a;山区80.98×108m^3/a,平原区51.80×108m^3/a。全省现有地下水开采机井约3.5×104眼,地下水开采量26.2×108m^3/a,地下水可开采资源量53.89×108m^3/a。西部地区开发利用程度较高,尤其是石羊河的民勤县地下水严重超采。东部和南部地区开发利用程度较低。  相似文献   

11.
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco.  相似文献   

12.
Robert L. Linnen   《Lithos》2005,80(1-4):267-280
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species.  相似文献   

13.
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414.  相似文献   

14.
Calcite samples were extracted both from the rock matrix and the superficial coating of a karstified fault plane of an underground quarry, located in the eastern border of the Paris basin. The karstification is dated as Quaternary. Analysis of mechanical calcite twinning reveals that only the calcite matrix has also undergone a compression trending WNW that can be attributed to the Mio-Pliocene alpine collision. Both coating and matrix have undergone a strike-slip regime with σ1 roughly trending north–south, that could correspond to the regional present-day state of stress, a strike-slip compression rather trending NNW, modified by local phenomena. To cite this article: M. Rocher et al., C. R. Geoscience 335 (2003).  相似文献   

15.
正The Kuqa depression deposited thick rock salt,which has a lower density than surrounding rocks.When salt bodies form a certain scale,obvious negative gravity anomalies can be detected in the surface.Therefore,gravitational method can quickly obtain the shape,plane distribution of deep-seated salt bodies and overall tectonic morphology of the basin.  相似文献   

16.
正1 Introduction The Pingluoba brine,which characterized as high concentration with sodium,potassium,boron,lithium,and rubidium,possess great development value.The main composition of the brine can be summarized to the  相似文献   

17.
正1 Introduction In the present paper,MgCl2·6H2O,FeCl3·6H2O,and CeCl3·6H2O were used as raw materials in the precipitationhydrothermal method to synthesize MgF eC e hydrotalcite.The effects of the Fe:Ce molar ratio on the composition,crystal structure,and thermal stability of hydrotalcite are examined.Energy-dispersive X-ray spectroscopy(EDS),X-  相似文献   

18.
正1 Introduction Crystallization is one of important unit operations in the chemical production process,which requires not only the crystal product with high purity and yield,but also the available particle size of the crystal products to ensure product quality.Crystallization process is affected by  相似文献   

19.
正Dear Authors and Readers:First of all,on behalf of the new Editorial Board,I would like to express our sincere appreciation for your continuing support of our journal.This journal,founded in 1922,is the oldest geological journal in China.As the flagship journal of the Geological Society of China,it has become more and more influential in earth sciences in China and beyond.The journal is now indexed by SCI,CA and more than 20 other databases,with an impact  相似文献   

20.
正20141283 Bai Daoyuan(Hunan Institute of Geological Survey,Changsha 410016,China);Zhong Xiang Nature,Origin and Tectonic Setting of Jinzhou Basin in the South Segment of Xuefeng Orogen(Geology in China,ISSN1000-3657,CN11-1167/P,40(4),2013,p.1079-1091,10 illus.,47 refs.)Key words:foreland basins,strike-slip faults,Hunan Province  相似文献   

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