Probably you would like to use EM, electrical resistivity and GPR.

If shallow parts are targeted (aquifer is close to the surface), GPR can be a good tool. For seeing bigger scale and deeper parts, definitely EM is the tool to use and it can be used in airborne mode as well.

I agree with Sajad. But most widely used is electrical resistivity method.

Various methods of Geophysical prospecting used for groundwater are the Magnetic, Gravity, Seismic and Electrical. Of all these methods, electrical resistivity prospecting has acquired greatest importance in groundwater investigations and this is mainly due to the large and detectable variation in the resistivity values with the quantity of water in a rock. The resistivity of water bearing rocks largely depends on the amount of water they contain, the chemical composition and temperature, and the distribution of water. The other reasons of preference for electrical resistivity survey are, relative simplicity of instruments and their operation, relatively low operation costs, a depth range commensurate with the depths required in most groundwater problems, suitability to a wide spectrum of subsurface problems and easy methods of interpretation.

There are several methods as well as devices for geophysical research in the field of hydrogeology.

I agree with Sajad and N B Narasimha Prasad . But most widely used is electrical resistivity method.

Various methods of Geophysical prospecting used for groundwater are the Magnetic, Gravity, Seismic and Electrical. Of all these methods, electrical resistivity prospecting has acquired greatest importance in groundwater investigations and this is mainly due to the large and detectable variation in the resistivity values with the quantity of water in a rock.

The resistivity of water bearing rocks largely depends on the amount of water they contain, the chemical composition and temperature, and the distribution of water. The other reasons of preference for electrical resistivity survey are, relative simplicity of instruments and their operation, relatively low operation costs, a depth range commensurate with the depths required in most groundwater problems, suitability to a wide spectrum of subsurface problems and easy methods of interpretation.

If I have to chose one method, it would be electric resistivity.

Thank you very match Dear, Sajad Jazayeri, N B Narasimha Prasad , Mirko O Stankovic and M. Rashed for your answers.

Mr. Mirko, of the 4 paras of your above answer, 3 paras are just "copy & paste" of my earlier answer. If your intention was to re-highlight my answer, then it should have been within quotes (''......").

Thanks a lot for your help dear Prof N B Narasimha Prasad.

And I apologize for your comment of your answer on my question.

Electrical resistivity methods (ERT and VES) are the most widely used geophysical methods for hydrogeologic investigations and have always provided reliable results, even in complex geologic terrains.

Thank you very much dear Ebong D. Ebong for your answer.

If I have to chose method, it would be electric resistivity and Gravity method. But the best results have been shown shown by electrical resistivity methods (ERT and VES) that are most widely used geophysical methods for hydrogeologic investigations and have always provided reliable results, even in complex geologic terrains.

I agree with you, Honorable Mr. N B Narasimha Prasad. Nothing personal, I just supported you in your thinking because that practice confirmed it. Why not quoted - I made a mistake but I do not think I misused your opinion. Again, I emphasize - this is a well-established practice in these research.

Best regards, Mirtko!

I agree with the previous answer that ERT methods are the most useful for hydrogeology. But if you are interested in locating water bearing fractured zones, electromagnetic methods can be also very useful, for example, VLF, or Slingram type conductivity meters. They have the advantage of a much faster data acquisition.

Thanks a lot dear, Fernando César Moura de Andrade for your answer.

Dear Khelifa

A simplified conceptual model of a hydrogeological system implies two component the matrix (soils and/or rocks) and the fluid. This trivial conceptual model implies a geo-mechanical / hydro-physical characterizaton of the two components in terms of some physical parameters (structure geometry, bulk moduli, density, porosity, saturation, permeability, resistivity,temperature...the main). So that, the most suitable geophysical methods should be those that better characterize (directly and/or indirectly) the two components in term of some physical parameters.

The great issue of the geophysical prospecting in the field of hydrogeology (==hydrogeophysics) is the "entanglement" between the geo-mechanical and an hydrophysical parameters for an hydrogeological system at macroscopic equilibrium (see for example Archie factor formation relationship and the experimental works oriented to the definition of the involved exponents and parameters: tortuosity, saturation, porosity). This problem reach an high grade of complexity when we want to characterize the hydrogeological system also in dynamic conditions (drained/undrained system with forcing).

I think that an integrated geophysical approach should be adopted mainly based on the:

-geoelectrical parameters obtained with electrical DC, IP, EM and GPR methods as "proxy" of the hydrophysical status.

-seismic velocities and derived bulk moduli obtained with refraction P-S, reflection P-S, MASW seismic methods as "proxy" of the geo-mechanical status.

Obviously the choice of the method also depends on the prospecting scope, target objective and scale (in space-time) if we want to:

-reconstruct an image of the near surface structures characterizing the hydrogeological system with some geophysical parameters (for example water resource characterization) [static condition]. For example if you want explore the water resource in carbonatic units, combined resistivity(VES/ERT)+seismic(Refraction/reflection) imaging is optimal.

-support the studies on reconstruction of the hydrogeological processes by characterizing the changes in the hydrogeological system by monitoring changes in geophysical parameters [dynamic condition]. In this case time lapse geophysics integrated with multiparametric chemical-hydrogeological measurements should be indicated. See for example our work on saltwater intrusion in Venice lagoon based on short-long scales Time Lapse - resistivity Tomography, water resistivity survey, and hydrogeological measurements.

Thank you dear Prof.Roberto De Franco for your answer.

A very interesting answer, Thanks.

Ultimately the answer to your question will depend on the nature of the hydrogeological investigation. With the answers above in mind, you should do a literature search to see what previous practitioners have done and see if you can extend their methodologies to your problem.

Also, I would be remiss if I didn't plug the induced polarization and nuclear magnetic resonance techniques. They are high risk/high reward methods with the potential to unlock unique and critical hydrogeological properties (e.g. water content, permeability). If you can find a collaborator who knows how to use them, I'd recommend giving it a shot! Otherwise stick with the simpler methods like ERT/EM/seismic.

Good luck!

Thanks a lot dear, Gordon Osterman for your answer.

Electrical resistivity and seismic

Thanks, dear Guillermo Miró Pagés .

Electrical resistivity and electromagnetic are powerful methods in groundwater prospecting. DC resistivity technique is very appropriate in determining the subsurface layers at shallow depths with a high resolution. On the other hand, TEM technique is more effective than DC resistivity technique in detecting more details of subsurface layers that could not be detected by DC method, especially in the deep depths. Accordingly, it is highly recommended to apply TEM and DC resistivity techniques together in groundwater studies.

Thank you dear Ismael Ibraheem for your contribution.

Electrical resistivity and seismic refraction methods mostly used in field of hydrogeology

Many thanks, dear Zaidoon Taha Abdulrazzaq for your answer.

1. Electrical resistivity

2. Electromagnetic method

but when it comes to interpretation electromagnetic methods present more accurate results.

Dear Dr. Khelifa,

I agee with Dr. Roberto De Franco, It's answer is very interesting because the most interesting method is that we can use to better characterize the physical parameters you want to find. If you want to investigate the groundwater especially in Algeria, the cheaper method is VES/ERT, because it's very diffecult to find the other instruments of sismic or gravity or EM except in USTHB or CRAAG. I wanted to do a combination of methods in my Phd thesis (in Algeria) to study an hydrogeological problem but any company want to give me the material.

thanks

Electrical resistivity Tomography (ERT), I guess.

Thank you very much dear friends for your contribution.

Resistivity method

Many thanks, dear Anas Jafar Mohammed

Although other delineative geophysical methods like seismic refraction, magnetics, gravity etc. can be useful in hydrogeology, electrical resistivity is the most suitable based on the documented reports.

Thank you very much, dear Nyakno jimmy George, for your comment.

electric tomography and ground penetriting radar gpr

Many thanks, dear Oualid Melouah, for your answer.

Electrical resistivity Tomography (ERT), Vertical Electrical Resistivity and Seismic Refraction Methods are mostly

Recommended

Delineation of groundwater resources is more convenient with Vertical Electrical sounding method and electrical tomography.

In the field of hydrogeology, VES and ERT are most useful.

Dear K. Hami,

Many geophysical techniques exist for groundwater investigation. The most popular ones are the electrical and electromagnetic techniques. Within the electrical family, vertical electrical soundings, VES, electrical resistivity profiling and dipole-dipole field procedures are very outstanding. Most atimes, the actual procedure to use is determined by economic considerations, availability of space and the requirements of your clients. This is why many people prefers to use VES while the other procedures remain at academic domains.

The electromagnetic technique is also very useful in places where the equipment exist. Besides, seismic refraction, self potential and complex conductivity measurements can also be used. My personal experience with these techniques is that better subsurface models can be obtained if high sensitivity instruments coupled with highly experienced operator are used for the data acquisition.

Good luck.

Thank you very much, dear Anthony E. Akpan , for your comment.

Dear Khalifa, resistivity methods(1,2,3-D) highly recommended if you want to explore the shallow aquifer(s) integrated with shallow refraction seismic. However in deep groundwater aquifer electromagnetic methods (time and or frequency domains) is recommended in integrated with seismic reflection.

Many thanks, dear Dr. adel Kotb , for your answer.

"Situational" and "Locational" blindness (lack of appropriate illumination) issues should be well understood.

Indirect and direct methods in combination help here. Based on a broad but clear understanding of system of interest, two appropriate energies could be selected, to purpose, given above said.

Thank you very much, dear Bilal Hassan, for your comment.

Geoelectrical methods are more appropriate (VES Resistivity) in gravel - sand aquifers. If you are exploring for carst water, may be interesting to use IP also for clay filled carst discrimination. SP may give negative (generally) anomalies if you have water circulation. Magnetic resonance is very useful but more expensive.

Many thanks, dear Altin Karriqi, for your answer.

I am neither a hydrogelogist nor a geophysicist but in general, the method depends on the problem. Your most common method will not be used unless the problem to be solved is routinely the same.

Obianuju P. Umeji

I think the following link may help you:

Article The uses of geophysical methods in hydrogeological investiga...

Very interesting document.

Thank you very much, dear Mahesh Kumar, for your comment.

Of course, the most use geophysical methods in hydrology are electric and seismic. We can find many historical results in this direction, but there are another possibility that is not usually use, the EM. If you can know about this other possibility look for some applications in Brazil, Mexico and Uruguay. For example Julian Andres Ramos used this method in his MSc last year.

Many thanks, dear Willy Rodriguez, for your answer,

and your opinion.

Geoelectric followed by seismic (refraction).

Thank you very much dear Hilmi S. Salem for your answer.

Please see some of my publications on groundwater exploration, aquifer delineation, and petrophysical evaluation, using electric and seismic techniques (field measurement), supported by lab analyses and borehole logs. Examples of my publications can be found at (if needed, please cite them in your future publications (studies, reports, papers, graduation projects, conference presentations, etc.)):

Article Determination of fluid transmissivity and electric transvers...

and

Article Modelling of Lithology and Hydraulic Conductivity of Shallow...

and

Article Determination of Porosity, Formation Resistivity Factor, Arc...

and

Article The Influence of Clay Conductivity on Electric Measurements ...

and many others posted at:

https://www.researchgate.net/profile/Hilmi_Salem/publications.

Regards. --- Hilmi

Prof. Dr. Hilmi S. Salem

Geoelectric, seismic and electromagnetic methods.

Dear Hami,

Check out these articles.

Good luck

Thank you very much, dear Ebong D. Ebong, for your comment,

Very interesting document.

My experience shows that Electrical Resistivity Methods are the most successfully applied in hydrogeology.

Thank you very much, dear Nikolay Stoyanov, for your comment.

Most of hydrogeologists use Electrical Resistivity.

Many thanks, dear Y. Bouhadad , for your answer

The best and most used method is the Electrical Resistivity Surveying.

You can perform a set of Vertical Electrical Sounding (VES) surveys in your area. Also, you can use Electrical Resistivity Tomography (ERT). With ERT, you can even identify the type of groundwater or the contact between saline and fresh water and so on.

Thank you very much, dear Ahmed Abdelmaksoud , for your comment.

Geoelectric and Electromagnetic are most useful in the field of hydrogeology.

Many thanks, dear Yasin Nasuti, for your answer

A combination oficial geoeletric and seismic methods I suppose

Thank you very much, dear Leandro Adriano, for your comment.

I think geoelectric, seismic and electromagnetic methods.

Many thanks, dear Abdulvahab Sharif Mukhtarov, for your answer

good morning ground penetriting radar can gives effective solutions to your problem ,electric tomography is a good alternatives also

good luck

Thank you very much, dear Oualid Melouah, for your comment.

Electrical Resistivity techniques are the most suitable methods for hydrogeology

Many thanks, dear Nyakno jimmy George, for your answer.

Resistivity , S.P. , and I.P Methods add to TEM , VLF and MT Methods are considered the most geophysical methods which are useful in hydrogeology

Thank you very much, dear A. I. Ammar, for your comment.

Hello K. Hami,

In hydrogeology, geophysical techniques are usually deployed to map hydrogeological structures that can be broadly grouped into aquifer, aquiclude (or aquifuge) and aquitard. While planning to do this, one need to consider the depth to the aquifers (the porous and permeable geological materials that can store and transmit reasonably quantities of water and other fluids), geology of the area, the physical properties of the various lithostrata that under- and overlie the aquifers, economy of the conducting the investigation and equipment available. It is some of these considerations that make electrical resistivity and some EM techniques to be most popular techniques. However, where equipment are available, one can use still use seismics and IP techniques. I will not recommend MT but will rather cautiously recommend AMT. Always, remember that whichever technique is deployed, the essence is to map shallow lithostratigraphy based on the properties of the rocks and not the fluid. The aquifer layer can only be inferred from the results and correlating geophysical and geological models.

I hope that my response will be helpful to you.

K. Hami Geophysical prospecting methods best suited for hydrological studies are resistivity method, IP method, SP method, VES and EP methods.

K. Hami I hope this link will help you further;

http://www.geo.umass.edu/faculty/wclement/methods.html

Many thanks, dear Sajjad Munir, for your answer.

In choosing the best geophysical approach for Hydrogeological studies especially in Low income countries like Nigeria, several considerations must be put in place. Chief among them is cost. The financial capability to access some new and improved technology is seriously lacking. Second consideration would be availability. Some of the most preferred equipment are not available.

That said, in Basement Complex terrains, I believe GPR in combination with unconventional VES configurations will yield better results.

Generally, NMR is the best option considering its ability to detect Hydrogen ions directly.

Thank you very much, dear Jude Steven Ejepu, for your comment.

Electrical resistivity tomography is the best among the others. However, you can integrate between different geophysical methods. For e.g IP and resistivity.

Many thanks Tesfaldat for your contribution. Cheers

Thank you very much dea Yacob Tesfaldet for your comment.

In hydrogeology, geophysical techniques are usually deployed to map hydrogeological structures that can be broadly grouped into aquifer, aquiclude (or aquifuge) and aquitard, and movement of groundwater flow,

Thank you very much dear Omar Al-Khashman for your comment.

This depends on the depth of groundwater aquifer (s) . If the depth of investigation more than 400 m , the most promising method to detect the underground water basins is gravity method.

But if the depth of groundwater less than 400 m , the best method and most promising is the electrical resistivity method using Vertical Electrical Sounding Technique (Schlumberger Configuration).

If the depth of investigation is less than 10 m , It is preferable to use GPR.

Best Regards

Many thanks, dear A M S Abd El Gawad for your answer.