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1.
泰安地区岩溶富水构造激电测深法异常类型   总被引:2,自引:0,他引:2  
大量的抗旱打井找水开发深层岩溶地下水资源实例证明,泰安岩溶区不同岩溶形态富水构造激电测深异常类型及成因有一定规律可循.富水构造上的电测深曲线异常类型可划分为缓升型、缓降型、低阻V型、低阻平台型,富水地段电测深视电阻率断面等值线异常类型可划分为低阻台阶型、低阻梯度带型、低阻U型.以溶洞等岩溶形态为主的富水带引起相对低视电阻率、低视极化率、低半衰时及衰减度低异常,出现激电测深法多参数“同步低”异常;以断层构造破碎为主的富水带引起相对低视电阻率及低视极化率异常,产生相对高半衰时及衰减度极大值异常,出现视电阻率与激电测深法多参数“反相”异常.  相似文献   

2.
不同水文地质条件下地下水的分布规律对各种物探勘查方法可能存在不同的地球物理响应。经对水文物探方法的试验研究,在山前戈壁不均匀含水区寻找可采第四系地下水,采用井旁测深试验、垂向电阻率测深扫面、激电测深详查和水文电测井等方法的直流电测深法优化组合勘查,取得了找水效果新的突破。研究结果表明:电阻率测深参数视电阻率(ρs)、激电测深参数极化率(ηs)、衰减时(St)、综合参数(Z)等的变化,与地层岩性结构、地下水矿化度高低及含水地质构造的分布相关;激电测深参数与地下水富水程度关系更为密切。  相似文献   

3.
湘东地区红层盆地地下水勘探一直是一个难题,这里主要探讨采用综合地球物理方法研究该地区找水的有效性。结合工程实践,首先采用激电中梯扫面划分区内次级构造,确定低阻含水构造的水平位置;其次采用直流充电法电位梯度测量分析已知井部位地下水的连通性;最后利用激电联合剖面法和激电对称四极测深确定低阻带的垂向展布形态。同时,进一步开展高密度电法研究布设孔位和反演视电阻率异常之间的关系,最终确定钻探井位。后期的钻探结果表明,激电中梯扫面异常比较直观,地表水平定位方面比较精确,激电测深视电阻率二维反演结果能够有效反映低阻带垂向展布形态,两种方法相结合对湘东地区红层盆地地下水进行综合勘探是一种行之有效的方法。  相似文献   

4.
极化水平层上天然场源激电测深的理论研究   总被引:6,自引:0,他引:6  
采用Dias模型表征介质的激电效应,对三层水平地层中间层为极化层的天然电磁场源激电测深之视电阻率及阻抗相位进行了理论计算.利用中间层充电率m2≠0和m2=0时相同频率的视电阻率振幅比和阻抗相位差作为提取激电效应的参数,重点讨论了不同电阻率断面类型对激电测深异常的影响.最后,给出了在一个已知铅锌矿上的试验结果.  相似文献   

5.
乌蒙山贫困缺水区水资源严重缺乏,找水需求大、难度大。为确定了ZK12探采结合井位置,本文首先分析了工区找水环境因素的地层时代、含水介质类型、构造背景、水源条件和水动条件等5个条件;其次,对富水特征的含水岩组、蓄水构造和富水地貌进行研究;最后,重点分析地球物理特征找水因素,介绍了视电阻率联合剖面法、大地电磁测深法、瞬变电磁法、激电测深和地球物理测井等“多方法”应用效果,通过视电阻率、视极化率、衰减度、半衰时等“多参数”,确定断层裂隙水的地球物理特征,建立由浅入深的“多层次”地球物理模式。最终,创新性提出了乌蒙山连片贫困缺水区重点村镇的“多方法、多参数、多层次”地球物理找水模式,克服单一物探方法找水的局限性,精准定井位,对地下水勘查起到示范作用。   相似文献   

6.
黄河水库南屯进行勘查的主要目的就是通过物探方法初步查明地下溶洞存在的情况以及区内的地质概况,为该区地质灾害的评价提供必要的参考依据。通过多种物探方法实验,发现激电中梯、激电联剖及视电阻率测深效果相对较好。由于区内地下水较发育,而且已知塌陷部位都不同程度的含水,水导电性能好.。因此,在地表观测时呈现视电阻率低阻趋势。当溶洞中没有地下水存在时,视电阻率呈现高阻异常。这样就可以通过视电阻率的反映来发现地下溶洞。  相似文献   

7.
研究剩余电磁效应的理想参数   总被引:2,自引:0,他引:2  
在频谱激电法中利用剩余电磁效应(REM)研究地下电性分布已引起人们的重视。本文基于对数值计算结果的分析指出,选择适当高频fG,以偶极装置观测视复电阻率的相位φs0(fG),用相应条件下均匀大地的视复电阻率相位理论值(fG)对其作归一,所得比值参数φs0(fG)/(fG)是表示剩余电磁效应的理想参数。文中还结合数值计算结果和野外实测资料,分析了这一参数的异常特征和在油气探测中的应用效果。  相似文献   

8.
金属因素在激电异常评价中的应用   总被引:2,自引:0,他引:2  
当激电异常较为复杂时,利用ηs(或Fs)这些激电法的基本参数难以对异常源的性质进行合理的解释.通过具体实例,说明应用激电法的二次信息--金属因素解释复杂激电异常的有效性.金属因素能将矿致异常与非矿致异常分离,对异常的定性及定量解释有很好的作用.  相似文献   

9.
吴之训 《物探与化探》1987,11(4):281-290
通过野外实例说明激电谱的视时间常数(τs)的稀释作用小,岩矿的时间常数差异大有可能发现为激电强度参数(ηsρsms或ψs)所不能发现的深部矿(或矿化)体的异常.以τs参数为主,综合激电谱的其它参数,有可能对浅源激电异常性质进行区分.  相似文献   

10.
介绍了不对称测深法装置的测深原理;在吉林某地进行了激电测深勘探,结果显示:正向单极-偶极和反向偶极-单极采集的视电阻率、视充电率原始数据在拟断面图的分布特征,和大地电磁测深原始数据受到的静态效应类似,视电阻率、视充电率受局部地形和电磁噪声的影响,在拟断面图中呈假的带状异常。正向单极-偶极、反向偶极-单极装置获取的视电阻率、视充电率数据也可分别进行二维反演,但联合单极-偶极/偶极-单极装置测深二维反演地质结果最好,具有采集的数据量大、激电信号强 、穿透深度大、勘探精度高等优点,根据视电阻率、视充电率二维反演在地电断面成像技术,能够准确确定电性异常体的空间分布,为钻探验证电异常提供准确的地球物理依据。  相似文献   

11.
The study examines a water exploration and poverty alleviation project in Guyuan county. The study analyzes correlations between aquifers and multiple induced polarization (IP) parameters, including resistivity, polarizability, deviation, half decay time, water-bearing factors, and Kc, a new parameter refined in this study. Based on the study, the well was placed accurately, and its maximum water inflow reached 30 m3/h. Kc value highlights the rate of change at early stages of IP secondary field. Kc value served as a quick indicator in this groundwater prospecting and is validated in practice. Progress has been made in finding new parameters in exploring water with IP method. Thanks to the project, local people have access to water and poverty alleviation has scored some achievements.  相似文献   

12.
激电异常解释中金属因素的应用   总被引:1,自引:0,他引:1  
工作区地处西伯利亚与哈萨克斯坦一准噶尔这两大板块之接合部位的陆缘裂谷带附近,重要有色金属矿床多分布于额尔齐斯深大断裂两侧,有很好的成矿前景。采用激发极化法圈定激电异常区,在异常评价中,用提取激电二次信息的视金属因素(以)法,突出低阻极化体异常,压制高阻极化体异常,强化矿致异常,压制非矿致异常干扰,成功区分矿与非矿异常。通过求取视金属因素,圈定了重点勘查区域,并在重点勘查区域布置测深剖面,指导了钻孔的布置。钻探见矿验证了激电法在该区应用效果良好。  相似文献   

13.
Hydrogeophysical investigations of the Pleistocene aquifer at the Kom Hamada area, Egypt, have been conducted to determine the characteristics of groundwater. The main water-bearing formations in the study area are composed of Quaternary deposits. Water samples were taken and chemically analyzed at 29 sites. The constructed iso-salinity contour map of the study area showed an increase in salinity from 451.75 mg/l at eastern parts to 1,091.85 mg/l at western parts. The groundwater of the study area showed a hydrochemical evolution from Ca–HCO3 at the eastern side to Na–Cl at the western side. Some of groundwater constituents have high concentration values exceeding the safe limit for drinking. Eighteen vertical electrical soundings (VES) were conducted in the study area. These soundings were conducted near existing wells to obtain layer parameters of the various penetrated layers and to calculate the petrophysical characteristics of the aquifers. The resistivity of the first water-bearing layer ranges between 34 and 47 Ω m. The thickness of this layer ranges between 26 and 79 m. This layer represents the first aquifer, where it is followed by another water-bearing layer with resistivity ranges between 29 and 62 Ω m and extends downward. The two aquifers are hydraulically connected. Variation of the resistivities of these two water-bearing layers is mainly due to the lithological variation. The resistivity values along with the TDS values of the two water-bearing layers indicate fresh to brackish water types.  相似文献   

14.
依据提供的物性参数的不同,广泛应用于找水工作的电法手段可分为电阻率法和激发极化法两大类,其中电阻率法提供电阻率参数,主要解决与赋水有关的构造问题(如赋水层位或断裂构造)。方法上有常规电法、电磁法,可根据地区赋水部位的不同选择适当的方法。激发极化法则利用含水层的激发极化效应进一步确定目标层位或构造的赋水性。电阻率法和激发极化法相互配合,在找水工作中相得益彰。  相似文献   

15.
Integrated geophysical techniques including resistivity image, vertical electrical sounding (VES), and seismic refraction have been conducted to investigate the Wadi Hanifah water system. The groundwater in Wadi Hanifah has problems caused by the high volumes of sewage water percolating into the ground. The combination of VES, resistivity image, and seismic refraction has made a valuable contribution to the identification of the interface between the contaminated and fresh water in Wadi Hanifah area. The contaminated groundwater has lower resistivity values than fresh groundwater due to the higher concentration of ions which reduces the resistivity. Resistivity image and sounding in this area clearly identified the nature of the lithological depth and proved useful at identifying water-bearing zones. Fresh groundwater was found in the study area at a depth of 100 m within the fractured limestone. Water-bearing zones occur in two aquifers, shallow contaminated water at 10 m depth in alluvial deposits and the deeper fresh water aquifer at a depth of about 100 m in fractured limestone. The interface between the contaminated water (sanitary water) and fresh water marked out horizontally at 100 m distance from the main channel and vertically at 20 m depth.  相似文献   

16.
在胶莱盆地,其红层所属地层岩性为粉砂岩、泥岩,含、透水性较差,查找低阻断裂构造是其地下水勘探的唯一途径。而红层地区的压扭性断层,会因挤压密实的断层泥存在,导致单纯利用低电阻率参数判定地下水的赋存位置出现差错。根据该区地下水的自然电位异常值约为-100mV、含水破碎砂岩极化率大于2%、衰减度D大于50%的特点,提出了自然电位观测法与激发极化电测深法相结合的组合方法。即利用自然电场法进行剖面测量,判定含水异常位置,然后利用激发极化电测深法准确判定地下水所在层位及埋深。在胶州市某镇政府水源勘探中,利用该组合方法,成功的圈定了3个井位,并在预定的深度内打出了单井出水量为1000t/d的优质井。  相似文献   

17.
隧道前方含水构造的超前预报是地下工程领域中亟待解决的难题。基于频域激发极化法中频散率参数对水体响应敏感的特点,将其引入到隧道含水体超前探测研究工作中。从理论正演、物理模拟、解译方法等方面入手对频域激发极化超前预报技术进行了系统的研究。利用三维有限元数值模拟技术解决了隧道中频域激发极化超前探测的数值正演难题,并通过对典型含水体的正演研究得到了视频散率对含水构造的响应规律,发现视频散率曲线的极大值是表征掌子面前方含水构造存在的重要特征;基于大量数值正演的结论,提出了一种利用两次探测的视频散率曲线极大值联合判断含水构造位置的方法;物理模型试验和现场实际应用表明,频域激发极化法预报的含水体位置与实际情况基本一致,验证了该方法用于隧道含水构造超前探测的有效性,为解决隧道含水构造超前探测这一难题提供了可行的途径。  相似文献   

18.
曹崇本  周世恩 《贵州地质》2014,31(3):223-228
岩溶地下水的富集是极不均匀性的,寻找和查明岩溶蓄水构造的空间位置及其结构,是在岩溶山区寻找地下水源地的前提.本文通过对贵州省岩溶地下水富集条件的分析、归纳,将岩溶蓄水构造分为两个大类共七个类型,并利用地质体电阻率的统计结果建立了各类型岩溶蓄水构造的电阻率物理模型.实际工作表明,利用岩溶蓄水构造的电阻率物理模型,对提高岩溶山区找水打井的成功率具有指导意义.  相似文献   

19.
The alluvial aquifer is the primary source of groundwater along the eastern Dead Sea shoreline, Jordan. Over the last 20 years, salinity has risen in some existing wells and several new wells have encountered brackish water in areas thought to contain fresh water. A good linear correlation exists between the water resistivity and the chloride concentration of groundwater and shows that the salinity is the most important factor controlling resistivity. Two-dimensional electrical tomography (ET) integrated with geoelectrical soundings were employed to delineate different water-bearing formations and the configuration of the interface between them. The present hydrological system and the related brines and interfaces are controlled by the Dead Sea base level, presently at 410 m b.s.l. Resistivity measurements show a dominant trend of decreasing resistivity (thus increasing salinity) with depth and westward towards the Dead Sea. Accordingly, three zones with different resistivity values were detected, corresponding to three different water-bearing formations: (1) strata saturated with fresh to slightly brackish groundwater; (2) a transition zone of brine mixed with fresh to brackish groundwater; (3) a water-bearing formation containing Dead Sea brine. In addition, a low resistivity unit containing brine was detected above the 1955 Dead Sea base level, which was interpreted as having remained unflushed by infiltrating rain.  相似文献   

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