电法找水在苏丹北恩堵曼省的应用

介绍了苏丹北恩堵曼地区不同地貌类型的电测深曲线类型及含水层的电阻率、极化率特征，强调了找水方法优化组合及选择合理有效的施测装置的重要性，指出了在不同地貌类型中物探找水定井位需注意的一些不利的水文地质变化因素。     

激电测深半衰时参数在东平山丘区找水中的应用

在东平山丘区缺水村庄的找水定井工作中,应用激电测深方法,结合区域水文地质条件,以激电测深参数视电阻率和视极化率基础,重点结合半衰时参数St进行综合分析,精确确定储水构造位置和富水地层深度。经后期地质钻探验证,确定的井位单井涌水量均在60 m3/h以上,解决了当地生产生活用水困难,为今后在类似地区的找水工作积累了经验。     

不同电法组合在找水中的应用

针对河南省新乡市凤泉区严重缺水的现状,利用高密度电阻率法、EH-4电导率测深和激发极化对称四极测深不同电法组合,在水文地质条件复杂的松散岩和基岩干旱地区找水取得显著的效果,总结出针对不同水文地质条件下的不同电法找水组合模式,不同电法组合模式的应用能为地下水勘查定井位提供可靠的科学依据,为机井工程成功率提供重要保障。     

岩溶山区和太行山区抗旱打井电阻率法运用浅析

电阻率法是水文地质物探在地下水找水方面较为有效的方法,但由于各地区地质条件的不同,在具体运用上具有差异。2010年贵州、2011年河南均遭大旱,贵州省地矿局均承担了抗旱打井工作,运用了电阻率法确定孔位效果较好。本文拟通过成功实例分析,并结合岩溶山区和太行山区不同的水文地质特征,对比电阻率法在不同地区的运用差异,总结电阻率法的使用、解译经验,为今后找水打井中电阻率法确定孔位的应用提供科学依据。     

火成岩侵入的石灰岩地区电法找水实践与认识

太行山前的大多数石灰岩受火成岩的侵入,造成这些地区的地下水分布极不均匀,施工成井率很低。为了合理有效地开发地下水资源,在工作区进行水文地质调查的基础上,垂直于主构造线方向布置了3条电阻率法勘探剖面线,运用对称四极电阻率测深法,分别测量了视电阻率值。通过绘制视电阻率等值线断面图,定性和定量解释火成岩侵入的石灰岩地区地下富水带在视电阻率等值线图上的表现形态,准确的确定了井位。通过钻探工程验证,水井的出水量较为理想,与物探推断分析得出来的结论吻合良好。在这类地区开展电法找水,研究水文地质条件是基础,野外工作布置要灵活,深刻分析视电阻率等值线的异常形态是关键。      

青海地区电法找水浅议

介绍了青海地区不同地貌类型的电测深曲线类型及含水层的电阻率、极化率特征,强调了找水方法优化组合及选择合理有效的施测装置的重要性,指出了在不同地貌类型中物探找水定井位需注意的一些不利的水文地质变化因素.     

地形及岩层产状对电测深找水的影响

探讨了地形对电测深找水的影响机理、视电阻率变化规律;针对沟谷、山坡等不同的地形地貌,全面分析了沿构造走向布极、垂直构造走向等不同布极方式对电测深的影响;探讨了了岩层不同产状要素电测深成果的影响;提出了减少地形、岩层产状对电测深成果干扰的应对措施,提高电测找水的成功率。     

河南巩义抗旱地下水井位确定和钻探方法

应用高密度电法开展河南省巩义市应急抗旱找水打井工作,发现巩义市东南部基岩山区深部含水层的电阻率为低阻,基岩电阻率总体为高阻; 西北部松散层的上部黄土电阻率为低阻,下部砂砾石松散含水层电阻率为高阻,从而提出了在该地区应用高密度电法勘查找水的新思路,即“基岩山区高阻中寻找低阻”和“松散层低阻中寻找高阻”。在巩义市打井20口,成井率100%,实践证明该思路是行之有效的。在应急抗旱找水打井工作中,在快速熟悉区域地质、构造和水文地质条件的基础上,开展多种物探方法(高密度电法、电测深、测井等)相互验证十分重要,可为在应急早期尽快统一认识、确定具体井位和避免打“干眼”提供重要技术支撑。应急抗旱找水打井工作通常时间紧、任务重,为确保完成应急任务,应根据应急找水任务工作量、应急时间和当地不同的水文地质条件,合理安排不同的钻探机械和钻井方式。     

电阻率法在阿联酋沙漠地区地下水勘探中的应用

通过对测区的水文地质条件和地球物理特征进行分析及判断,总结出在沙漠地区找水较为有效的方法.实践表明,利用电阻率法在该地区找水的成功率可达70%以上.     

常规电阻率测深法在阿拉善干旱荒漠区找水中的成功应用

针对腾格里沙漠南缘严重缺水的现状,开展了常规电阻率测深工作。综合地质、水文地质、电性参数等特征对测深曲线进行定性、定量精细解释,总结出电阻率在25Ω·m左右的新近系地层为砂岩、砂砾岩相对较厚,泥岩相对较薄区段,是该区域寻找碎屑岩类裂隙孔隙水的目标层位。钻探结果表明,轻便、经济的常规电阻率测深法在阿拉善干旱荒漠严重缺水区可以取得显著的找水效果。     

综合电法在祁连山山前缺水区寻找地下水的应用

应用电测深、激电测深和瞬变电磁测深方法,结合区域水文地质条件,在被前人判定为贫水或无水区的河西走廊祁连山山前缺水区开展了综合电法勘查找水工作,分别发现了分布面积广的第四系大厚度粘土层深部和第三系泥岩深部存在高阻含水体。经20余眼水文地质勘探孔验证,单井涌水量大于2000m³/d,矿化度小于1.0g/L,布井成功率达95%以上。不但彻底解决了这一地区人饮水源的问题,而且为今后类似地区的找水工作积累了经验,具有显著的社会效益。     

利用电测深曲线极大值计算水文地质参数的探讨

利用电测深成果(含水层电阻率或地层因素)估算含水层渗透系数的问题,前人已做了很多工作^[1,2].作者针对安阳市安阳河北水源地电测深资料的解释和水文地质勘察成果,提出采用电测深K型曲线极大值计算水文地质参数的方法,建立了ρ_{s max}～K之间的4种回归分析模型.结果表明,K与ρ_{s max}存在对数相关关系.经计算的成果图件(K、T等值线图)对评价该区水文地质条件,估算单井涌水量及水井位置选择等都具有十分重要的实用价值.     

Delineation of groundwater resources using electrical resistivity tomography

Chandrabhaga basin of the Nagpur district is a part of the drought prone Vidarbha region of Maharashtra, India. This region is facing acute shortage of water for drinking and irrigation purposes. The basin is located at the eastern fringe of the Deccan traps consisting of volcanic rocks. Presently, dug wells penetrating composite layers of the weathered mantle and highly fractured rocks overlying stratified basaltic lava flows are the main source of water supply. However, water available in the dug wells is inadequate to meet the ever increasing demand for water causing considerable economic losses to the farming community. In this work, we present the results of an electrical resistivity tomography (ERT) survey carried out in the basin for the delineation of groundwater potential zones. Validity of the hydrogeological setup obtained from the ERT results has been confirmed by bore well drillings at two investigated sites. The study demonstrates the efficacy of the ERT technique in delineation of groundwater potential zones in the hydrogeologically complex basaltic terrain of the Deccan traps.     

云南泸西盆地边缘既比岩溶水勘查及应急抗旱示范工程

既比处于泸西盆地下游边缘,岩溶发育均匀性差,地表干旱,严重缺水,打井找水难度较大。文章论述了既比地区的水文地质条件、地下水分布赋存特征,介绍了岩溶区地下水勘查布井的工作方法;利用高密度电法、激电测深物探成果,结合水文地质调查成果,确定了井位,结果证实钻孔水量丰富。分析认为岩溶含水层富水性差异主要受溶隙充填、连通程度控制,总结出一套以岩溶水开发利用为龙头,抗旱与节水喷灌高效农业发展相结合的应急抗旱模式,经济效益显著。提出了开发利用地下水的管理措施建议。      

Combined ground-penetrating radar (GPR) and electrical resistivity applications exploring groundwater potential zones in granitic terrain

Frequent failures of monsoons have forced to opt the groundwater as the only source of irrigation in non-command areas. Groundwater exploration in granitic terrain of dry land agriculture has been a major concern for farmers and water resource authorities. The hydrogeological complexities and lack of understanding of the aquifer systems have resulted in the failure of a majority of the borehole drillings in India. Hence, a combination of geophysical tools comprising ground-penetrating radar (GPR), multielectrode resistivity imaging (MERI), and vertical electrical sounding (VES) has been employed for pinpointing the groundwater potential zones in dry land agricultural of granitic terrain in India. Results obtained and verified with each other led to the detection of a saturated fracture within the environs. In GPR scanning, a 40-MHz antenna is used with specifications of 5 dielectric constant, 600 scans/nS, and 40 m depth. The anomalies acquired on GPR scans at various depths are confirmed with low-resistivity ranges of 27–50?Ω m at 23 and 27 m depths obtained from the MERI. Further, drilling with a down-the-hole hammer was carried out at two recommended sites down to 50–70 m depth, which were complimentary of VES results. The integrated geophysical anomalies have good agreement with the drilling lithologs validating the MERI and GPR data. The yields of these bore wells varied from 83 to 130 l/min. This approach is possible and can be replicated by water resource authorities in thrust areas of dry land environs of hard rock terrain around the world.     

Geophysical investigation of a mineral groundwater resource in Turkey

The hydrogeological conditions in Uludag (Nilufer River catchment, Bursa, Turkey) were assessed, using time-domain electromagnetic soundings, electrical resistivity and induced polarisation tomography, to detect the most promising zones for new water-well siting, in order to increase the quantity of water for bottling. The hydrogeological model is quite complex: deep mineral and thermal water rises from a main vertical fault which separates two lithological complexes. The highly mineralised (deep) water is naturally mixed with low mineralised water at a shallow depth, 30–40 m; the mixed mineral water is found in some surface springs and shallow wells, while the highly mineralised water is found at depth in some unused deep wells located close to the main fault. All the water points (springs and wells) are located inside a “mineral water belt” on the north side of the Nilufer River. The geophysical survey confirmed the hydrogeological model and highlighted four promising zones for well siting (zones with very low electrical resistivity and high induced polarisation anomalies, corresponding to the main water-bearing faults). One of the geophysical anomalies, the furthest from the exploited sources, was verified by means of a test well; the drilling results have confirmed the water mixing model.     

综合物探方法在水文地质勘查中的应用——以东宁市浙江工业园勘查为例

针对东宁市浙江工业园急需查找后备水源地的现状,利用高密度电阻率法与激发极化法组合,在对已知井观测研究基础上,建立勘查区地球物理找水模型.进一步对相关区域勘查,结合水文地质资料和成井条件圈定井位,经钻井施工验证,成井率100%.通过多种物探方法在该地区应用的实际效果分析,高密度电阻率法与激发极化法组合模式在区域相似的水文地质条件下,在地下水勘查的应用中能提高其找水和成井的准确性.     

EH-4连续电导率仪在西南岩溶地区找水中的应用

针对西南岩溶地区水文地质构造及富水性特征,利用EH-4电磁测深剖面的电阻率差异确定在缺水区域的井孔位置;并对典型案例进行介绍;最后对在工作过程中的经验认识进行总结概括,希望对今后类似地区进行找水起到一定的指导作用。     

Groundwater resources evaluation in calcareous limestone using geoelectrical and VLF-EM surveys (El Salloum Basin,Egypt)

Understanding and developing groundwater resources in arid regions such as El Salloum basin, along the northwestern coast of Egypt, remains a challenging issue. One-dimensional (1D) electrical sounding (ES), two-dimensional (2D) electrical resistivity imaging (ERI), and very low frequency electromagnetic (VLF-EM) measurements were used to investigate the hydrogeological framework of El Salloum basin with the aim of determining the potential for extraction of potable water. 1D resistivity sounding models were used to delineate geoelectric sections and water-bearing layers. 2D ERI highlighted decreases in resistivity with depth, attributed to clay-rich limestone combined with seawater intrusion towards the coast. A depth of investigation (DOI) index was used to constrain the information content of the images at depths up to 100 m. The VLF-EM survey identified likely faults/fractured zones across the study area. A combined analysis of the datasets of the 1D ES, 2D ERI, and VLF-EM methods identified potential zones of groundwater, the extent of seawater intrusion, and major hydrogeological structures (fracture zones) in El Salloum basin. The equivalent geologic layers suggest that the main aquifer in the basin is the fractured chalky limestone middle Miocene) south of the coastal plain of the study area. Sites likely to provide significant volumes of potable water were identified based on relatively high resistivity and thickness of laterally extensive layers. The most promising locations for drilling productive wells are in the south and southeastern parts of the region, where the potential for potable groundwater increases substantially.

     

淮北煤田松散层电性特征及富水性评价

根据淮北平原电测深资料结合钻探工作,评述了第四系松散层中砂质类和粘土类的电性特征及分布规律,对松散层中含水层各岩性的电性影响因素进行了分析,认为视电阻率与含砂量和颗粒度与正比,与矿化度成反比;介绍了含水层富水性特征参数的提取方法及电性参数与水文地质参数相关关系,认为视电阻率与含水层的渗透系数成正比.通过对电性资料的认识和区域水质资料的分析,获得了该区面积性水文地质参数.该区富水性评价成果已被实际水文地质资料验证.