Hydrogeology - Science topic

Hello, I am currently working on my undergraduate thesis, which focuses on modeling seepage through a dam. I am exploring the use of MODFLOW for this purpose, as it is widely recognized for simulating flow through porous media (based on information from the USGS website and my advisor's suggestion). However, I have been struggling to find relevant papers, case studies, or comprehensive tutorials to guide me in this specific application, which has left me feeling a bit overwhelmed. Additionally, the numerous add-ons and plugins available for MODFLOW make it challenging to understand their differences and how they might apply to my work. I would greatly appreciate any explanations, references, or resources that could help me better understand this topic. Thank you very much!

Importantly the features and the parameters to be considered

Software such as SOLVEQ-XPT, RTest and GeoT.

modern applications

LAND SUBSIDENCE

Whether capturing the minute variations in earth’s surface using continuous Global Positioning System; or, Extensometers; or, Interferometric Synthetic Aperture Radar would justify the spatio-temporal extent of land subsidence resulting from "petroleum" ‘reservoir compaction’?

In case, if we have a rise in groundwater table; or a groundwater recharge that directly leads to ‘soil swelling’ or an ‘uplift’ respectively (right above the petroleum wellsite), won’t the resulting soil behavior in the unsaturated zone lead to a significant subsidence at the surface level?

If so, then, how could we correlate such a land subsidence to be associated with (petroleum) reservoir compaction in the absence of a proper hydrogeological investigation?

Since, there is no actual reduction in piezometric level within the confined reservoir (pay-zone) thickness, whether, is it becoming too difficult to effectively analyze the mechanism of land subsidence associated with a petroleum reservoir (even, if we manage to deduce the data on the changes in reservoir thickness as well as compressibility)?

In case of a petroleum reservoir, whether the distribution of stress at the interface of a seal and the reservoir would follow the simple correlation, where the ‘total vertical stress’ remains equal to the summation of ‘reservoir pore pressure’ and the ‘effective stress’?

How do we ensure whether Terzhagi’s one dimensional consolidation theory (in the vertical direction) would remain highly sufficient; or, should we also consider the Biot’s coefficient taking into account the load transfer (or maximum and minimum horizontal stresses) on the lateral horizontal directions in deducing the changes in reservoir thickness?

Do we have a direct mechanism by which the data on (petroleum) reservoir compaction that would directly get translated into its equivalent land subsidence in the absence of directly measuring the changes in earth’s surface and reporting the land subsidence using InSAR?

In the literature, there are graphical (approximate) ways to estimate AEV from the soil water retention curve. I wonder, how can one more accurately estimate AEV according to its definition: the suction value at the transition from a saturated to an unsaturated state.

Assuming one has volumetric water content (VWC) vs. suction measurements from laboratory tests (HYPROP test), how can we leverage these values to estimate AEV?

Is it sensible to choose the suction value corresponding to the second largest VWC as the AEV?

Can some elaborate on the geochemistry/hydrogeology ?

Thank You

Due to the quite deep water level in boreholes (the depth of the borehole is around 700 m, depth to the water table is around 150-200 m) and a significant rate required for the test, airlift testing is chosen.

No observation boreholes located near the pumping one so drawdown may be measured only in the pumping borehole.

The idea is to set a level logger hung on a wire at the bottom of the borehole (without piezometer), then install an airlift system above it and carry out a pumping test.

My concern is that fluctuation of water level due to airlift work will be too high to be suitable for further hydrogeological calculations (estimation of hydraulic conductivity). In other words, there will be too much "noise" and no strait line interval could be defined to calculate the parameter.

Any comments are really appreciated.

Thanks in advance.

I wish to know if a PhD in hydrogeology is relevant in getting a job outside Academia, and if it is, what are the possible job opportunities?

How effective do you think satellite images are for groundwater exploration works? What is the most effective method of groundwater exploration by the way? Any idea?

So many articles are published online today regarding groundwater exploration works in different parts of the globe. Experts in the area (Hydrogeology) are using different methods to investigate groundwater availability and potentials in different areas. However, I didn’t see the levels of uncertainties of using one method or the other. I read one article today, where they used satellite images as major inputs to explore groundwater. But, there’s no information about the levels of uncertainty of their work. Should it be presented that way? How effective do you think satellite images are for groundwater exploration purposes? What’s the most effective method of groundwater exploration by the way?

Hello dear comunity,

I need help to check Multi-collinearity for groundwater conditioning factors, im using MCDM to target groundwater prospective areas

Im hoping that someone can answer my question

Thnks you,

The packed bed column (H = 2m) is filled with alternate soil (coarse) and sand samples. I want to study the residence time of my target compound but before that I require a tracer to monitor the flow for calculating the HRT. What are the suitable tracers available that are cost effective as well as inert (should not interact and adsorb on soil and sand)?

I would like to work on the estimation of the hydrogeological potential of an area from satellite images. However, I would like to do this without carrying out verification in the field

Many open source programs exist in the field of geology with all its specializa (Water resources , hydrology , Hydrogeology, Geostatistics ,Quality water .......etc) that many people are unaware of.

What software do you want to suggest to us ?

Thanks

Reghais Azzeddine

Hello Everyone,

I am a hydrologist and want to model baseflow (i.e. surface-water groundwater interactions) via the development of a numerical groundwater model (GW model). One of the critical input parameters for the development of the GW model is the hydrogeology of the catchment in question.

Bore-well lithology datasets required for preparation of hydrogeology map or Fence Diagram is very limited (2 borewell logs only), Since, my study area lies in the headwater mountainous region. I am planning to do an electrical resistivity survey for mapping the hydro-geology of the basin in the catchment area of 102 Km2. I have a few questions, in planning Electrical survey in the basin-

1. What could be the optimum number of resistivity profiles required for appropriate representation of hydrogeology of the basin?

2. How to identify the most appropriate locations for Electrical resistivity profiling representative of the basin under consideration?

I request you all to give suggestions in this respect.

Thanking You.

Regards

Rajat

Need research topics in the fields mentioned above, especially topics that might be related to oil and gas.

I need help on getting a research topic for my PhD dissertation, in the fields of seismics and earthquake geophysics. I will also appreciate suggestions in the field of hydrogeology.

hydro-geochemistry, hydrogeology, hydrochemistry, chemistry

Since histograms can be applied in many different field in Hydrogeology is it possible to use it for predicting aquifer type.

If you are aims to do a model based on aquifer parameters to discuss the Environmental impact problems such as land subsidence due to increasing groundwater withdrawal what are the requirements data?

It is exciting to see that this year’s Nobel Prize for physics goes to complex system studies. Fingering flow (wetting front instability) in unsaturated soils is a typical complex-system problem. The complex system is partially characterized by emergence and adaptation. For highly non-linear unsaturated flow, the emergent pattern is the fingering, and the corresponding adaptation principle is the optimality, such as the minimization of global flow resistance. Based on these ideas, I have mathematically demonstrated that the relatively permeability is a function of both saturation and water flux, while the traditional theory considers the relative permeability as a function of saturation only. The work was supported by experimental results and documented in a recent book

One key issue in applying the complex-system framework to unsaturated flow is to find a physical principle to describe the adaptation. To do that, does anyone have a more general principle than the minimization of the global flow resistance?

Can any body help me know the diffusion coefficient of Europium(III) in pure water and the relative literature. Thank you!

I working on aquifer parameters from pumping well data

Hello everyone,

I am new to hydro-chemistry and planning to analyze freshwater (pristine environment) water samples for trace element analysis using ICP-MS. I have gone through literature for identification of suitable filter type for in-situ sample filtration and found that people have used a variety of filter types Cellulose Nitrate/PES Filter/Millipore filters/Polytetrafluoroethylene/Ester cellulose millipore/Polycarbonate, etc.

I was wondering which could be the most suitable filter choice for freshwater sample filtration?

I request you to give your valuable suggestions in this respect.

Thanking you all.

Regards

Rajat

In one of the prior study I am referring to, they have collected the depth of each subsurface layer but do not have any other parameters like SPT N value. The study is about an aquifer system. They have not mentioned about the type of boring they carried out. What kind of other studies require only subsurface layer depths, but not other parameters? What are the field tests that can be used to estimate subsurface layer depths?

Is there any relationship between geologic or hydro-geologic domains (eg. sedimentary) and a range of rock strength or hardness?

Is it possible to rank geological domains on ranges of rock strengths?

Two major flow mechanisms for preferential flow in unsaturated zone are the existence of macro pores or structures and wetting front stability (fingering flow). Do you have any field evidence or theoretical arguments to tell which of the two mechanisms is more important?

What classical examples in the literature of contamination by agrochemical, herbicide, fungicide, insecticide and pesticide residues in groundwater in agriculture?

Please, can you suggest a high graphical resolution software for creating hydrogeochemical graphs, especially for Gibb's diagrams?

Hello all,

i am new to water chemistry, i have been looking at trends in the water chemistry parameters, and found there is significant decreasing trend in Stream-water temperature, Ca, Mg, Na, and chloride along with discharge both in the monsoon and non-monsoon seasons.

Like From Jan 1994, Jan 1995, Jan 1996...... Jan 2018 (for Non-Monsoon period) Sept 1994, sept 1995, sept 1996...................Sept 2018 (Monsoon period)

Note- watershed (1000 km2 drainage area, Western Ghats, India) is free from dams and other water structures.

What could be possible drivers of trends in the above parameters?

Please provide your valuable suggestions.

Thanks in advance.

Regards

Rajat

I wish to use gamma ray logs from a named field to estimate shear wave logs for the area.

Physically measuring depth of water in a borewell is very difficult. First we need to dissemble the cap of the borewell. Then we need to allow measuring tape inside borewell which is very tedious.

There are SONAR based technologies for this purpose. Based on the time required for sound waves to reflect from the water level, they determine the depth of water level.

How accurate are these methods?

Hello, I am starting my master's thesis work on a Peruvian project. They have limited budget, and do not have yet any piezometer on the site. They do have 3 small open pits (3-4 meters long, 1 meter wide, 7 meters deep) for soil characterization. All of 3 have water on the bottom, and they use this "level" as a measure for water levels. I am not sure if those levels are representative for the actual water level, as I think the water level can be much higher, and when cutting with these open pits, it just "falls" by gravity action. Do you have any experience with using open pits data for water levels?

Could you let me now any publication oriented to that question or discussing it ?

trying to work on the problems a mine face due to watery strata, but couldn't find the appropriate matter for study.  

I am new to hydrogeology but I want to understand what is required to be measured at the field or site which will form basis for MODFLOW FLEX 3D modeling.. I want to to know the specifics to be gotten at the site. The rivers, lake, recharge... where do I require resistivity, every form of measurements needed to be calculated, please I’d like to know and where I can get the information I need as well... thanks

I am doing a small research to review the water related open source tools / software (e.g FREEWAT).

if you have used/developed/ heard of similar tools,please share it with me ?

Thanks in advance

Hi

Would you please let me know if the following is accurate as an answer to the question:

Suppose we have sensors which measure the volumetric soil water content of a soil layer for a long period (more than 6 months) and also high temporal resolution (half-hourly). Could I assign the maximum in this dataset to the saturation point?

I understand that we do need to have a lengthy rainfall event, how long the event should be so that the above proposal works?

And if there is any other way that I can get to the saturation point of a soil layer from the volumetric soil water content data/sensors, please let me know.

Mostly focused on the topsoil and preferably only using the dataset.

I have Total iron content in water express in mg/L. I want to convert it into mEq/L in order to calculate it percentage. But I do not know how to do it because it not Fe(II) nor Fe(III) but total iron which is the sum of both. I do not know which charge I have to use or the method to overcome this issue.

Thank you in advance

Are there any easy ways or equations to estimate the recharge value from rainfall?

Dear all,

I would like to have feedback on your personal experience with autonomous resistivity meters. I know some systems are well documented, but your personal perspective and your contacts will be of great help to me and my research group.

The system we are looking for must be able to perform daily measurements with up to 100 electrodes. We want to be able to download datasets or change protocols remotely. The system will be powered with solar panels and batteries.

We instrumented a large scale site last summer for my doctoral project. About 400 electrodes were buried to monitor the hydrogeological behavior of the site. We plan to perform autonomous monitoring with some of these electrodes (about 100). Transient monthly measurements will be also carried out with the remaining electrodes. The sketch of the site configuration is attached below.

Thank you in advance for your advice or contacts.

Adrien

I am using the chloro-alkaline indices, but I don’t know if it is the right way.

We have a hydrogeological setting of triassic layers, which are characterised by a ground water flow and mixing system. We tried to separate the sources of the groundwater flow and mixing system via hydrochemistry (ions), isotopes (deuterium, oxygen-18, tritium, carbon-14, strontium-isoptopes and sulphur isotopes), and still is not enough information to understand fully the hydrogeological regime. Which could be other approaches or tracers to separate the different aged components ?

hydraulic researchers, hydraulic modelling

I have SP, Gamma and Resistivity (both lateral and N16-N64) logs along with Electrical Conductivity value of the water sample of the area (collected through tube well). I have calculated the lateral resistivity (Rt) for each depth. I am getting Silt, clay and sand lithologies in the borehole. I would like to determine the Formation Resistivity Factor (F), Porosity, hydraulic conductivity and permeability value correctly. Kindly help me with step wise procedures. 

NOTE: Archie constant a & m varies for different lithologies like silt, clay and sand. 

Looking forward!!

Regards,

Ashok

Aquifer studies

What reference studies (Book, Article, Tesis etc) you know used ER Method was applied using the Vertical Electrical Survey (SEV) technique (Wenner-Schlumberger, dipole-dipole arrays) for definition of intrinsic vulnerability index to water contamination underground?

Are there any studies that have used this method to set parameters for analyzing groundwater vulnerability to contamination por geoelectric layers?

What are the methods, techniques, lines of thought, university labs considered vanguards in hydrogeology?

Dear Everyone

I am working in an irrigation department. In this field we need to study hydrogeology. Regarding that I am interested in reading the research paper on current tend and research trend in Hydrogeology. Could anyone suggest me a good review paper on that?

Thanking you

Is there an average time (or order of magnitude) that rainwater resides on a soil surface? A kind of residence time or ponding time? I am looking at a natural soil (not urban), normal topography (not too steep, not too flat), moderate vegetation (grass but not trees), made of compacted clay (quite impermeable) in a temperate climate (e.g. Europe)

Thanks!

Hi all,

I'm gonna study the impacts of the rise of production wells numbers (for irrigation purpose), LU/LC changes on the groundwater in a flat area where  river branch, main canal and many irrigation and drainage canals run through. The main aquifer in this area is recharged from the surface water (i.e. river branch, main canals, and irrigation and drainage canals) and the infiltration of excess irrigation water. The aquifer is semi-confined to phreatic (leaky aquifer). In addition, it is highly conductive with hydraulic conductivity ranging from 80 to 100 m /day, that is because it consists mainly of sand and gravels with clay lenses. Unfortunately, there is no a systematic monitoring for the water level, water chemistry or actual management for this aquifer. There are too many research works in different ways (e.g. geologic, hydrogeology, hydrogeochemistry,..etc.) have been done. There is no actual estimation for recharge quantity, monitoring for the impact of the anthropogonic activities on this aquifer. I have studied some samples from  3 wells, 2 shallow wells (25 m deep and 2.5 inches diameter) and one deep (65 m deep and 8 inches diameter). One of the two shallows is hand pump tube well and located close to the urban area (in agricultural land) with peizometric level, 10.4 m  and nitrate concentration, 6 ppm. And the second shallow well is being pumping using pump machine and located in urban area, north east the first shallow well with approximately distance 1 km long, with peizometric level of 10.3 m and nitrate concentration, 100 ppm. The deep well (the third one) is located north the second shallow well with distance 1 km long, peizometric level is 10.3 m and nitrate concentration is 3 ppm, which located at agricultural land. The second shallow well and the deeper one are both located close to drain canal with its nitrate concentration not more than 40 ppm as literature's result . I believed that the highly pumping rate is the main factor that gives the high nitrate value for the second shallow well. I really need to study the large area with many urban areas surrounded by agricultural lands, and find out the pollutions anomalies. I will measure CFCs as indicator of the recent recharge, GMS model to simulate the nitrate transport and the future prediction of its concentration, main ions, N15  to find the source of the nitrate and total coliforms . I really interested to find a valuable solutions for such problem. So if some one interested to help me in such study or give me advises, ideas and recommendations to how can I study the nitrate pollution anomaly, estimate and quantify the groundwater recharge, and study the impacts of the high density of wells (for irrigation purpose) on the quality and quantity of the groundwater in this area, I will be greatly appreciate.

Hydraulic tests conducted across ever larger usually yield higher transmissivities/conductivities/permeabilities. There are a lot of theories around what the effect results from. Only to name two: heterogeneity and preferential flow. Thus, my question: Where does the scale effect come from? Do you think it is still controversial?

Interaction between surface water and groundwater in karst is so strong that in most cases it is not possible to split hydrological from hydrogeological approaches and methods .

im looking for an hydrogeological methods of interpreting the activity istopes of radium in groundwater and some relation of this isotops with the other physical and chemical parameters, cations, anions, pH, TDS, temperature ....

I am currently running a master program in Hydrogeology and i want to do a project which incorporates hydro and environmental geology.. i will appreciate any suggestions regarding a topic for my project.

Dear Researchers!

It is known that methods such as: GOD (Foster) and DRASTIC (Aller et al) and others are widely used. But are there new methods developed to evaluate the intrinsic vulnerability of the physical environment to loads or pollutants? and with easy application (accessible parameters)?

Researchers in hydrogeology, hydrogeochemistry, environmental geology

Our new textbook:

"GROUNDWATER ENGINEERING A Technical Approach to Hydrogeology, Contaminant Transport and Groundwater Remediation"

was finaly publishedby Springer.

This textbook employs a technical and quantitative approach to explain subsurface hydrology and hydrogeology, and to offer a comprehensive overview of groundwater-related topics such as flow in porous media, aquifer characterization, contaminant description and transport, risk assessment, and groundwater remediation. It describes the characterization of subsurface flow of pristine and polluted water and provides readers with easily applicable tools for the design of water supply systems, drinking-water source protection, and remediation interventions. Specific applications range from groundwater exploitation as a drinking water supply to the remediation of contaminated aquifers, from the definition and safeguarding of drinking-water sources to the assessment of human health risks in connection with groundwater contamination events.

The book represents an ideal learning resource for upper-undergraduate and graduate students of civil engineering, environmental engineering, and geology, as well as practitioners in the fields of water resource management and environmental protection who are interested in groundwater engineering and technical hydrogeology.

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The vadose zone is the first groundwater protection line, what are the main physical, chemical, biological and other elements capable of attenuating the potential contaminants released on the ground surface?

What is the difference between the hydrogeological system and the aquifer system?

We are currently characterizing aquifer in an area where there is paucity of hydrogeologic data and need some sort of secondary data to combine with our geophysical information and what is available is rainfall data.

I need to construct my 3D conceptual model considering the geometry (boundary conditions), topography, fluxes (precipitation, evapotranspiration, runoff, etc.), flow directions and so on...

How discharge is unsually conceptualized for catchments under arid or semiarid environments with no springs and only ephemeral rivers, in a context that could not be explained exclusively by evapotranspiration (i.e. no salinization, TDS increase, etc)? Could you suggest any reviews or insightful literature about this topic? Kindest regards to all.

Hydrogeology

Hydrology

Petrophysics

Well logging

Submarine groundwater discharge is a very common topic of research nowadays and there are a lot of studies investigating about it but when was this term invented and by who?

Looking in published papers the first time that I can find it was in 1991 by Vladimir Vanek and David Robert Lee in Limnology and Oceanography but maybe it has been used before?

I'm looking for codes that can do this for saturated and/or unsaturated porous media. I expect there are a few that can handle the porosity changes easily, but predicting permeability changes seems much more complicated.

Dear scientists of noble gas and hydrology,

Would equilibrium and/or excess concentrations of noble gases change after isolation from gas exchange with atmosphere? (Non-atmospheric noble gas was not taken into consideration in this question.)

Relationship of solubilities of noble gas and salinity were found and reported by Weiss (1970 and 1971), Weiss and Kyser (1978), Clever (1979 and 1980), Benson and Krause (1976), and Smith and Kennedy (1983). The higher salinity would lead to lower gas concentration if other parameters like temperature and pressure stay unchanged.

However, reported data was from air-water exchange interface like in unconfined aquifers or surface water system. Would it be available for groundwater in CONFINED aquifers? That is to say, would dissolved noble gas degas in confined groundwater due to the increase of salinity? Or would gas concentration stay undisturbed in groundwater flow system after isolation from gas exchange with air?

Any feedback, answers or discussions would be welcomed. And I would greatly appreciated for that.

Kind regards

Dan

These terms (sustainable yield and safe yield of an aquifer) are the most debatable terms in hydrogeology. People sometimes report their predicted yields of aquifer systems that show no considerable negative impact of the available groundwater potential of the aquifer system as "sustainable yield" and some experts report it as "safe yield". On the other hand, there are also confused reported that also confuse readers in terms of defining these terms. So, do they really have similar meanings? Is there any justifiable difference between these terms? Can we make an agreement on how/where to use these terms?

The question is that, how much can we trust the indicators like SPI and GRI and the other indicators that analyze the changes in groundwater levels in relation to precipitation? Due to the fact that in many regions, including arid and semi-arid regions, the water table is very low and most likely due to high evaporation, rain does not play a role in groundwater recharge. Based on my Experiences in the assessment of groundwater in Kashan, located in the center of Iran in an arid and semi-arid region, precipitation does not feed the groundwater (based on the analysis of tritium and carbon-14 isotopes). It seems that in the subject of the effect of meteorological drought on the hydrogeological drought, isotope investigation could be so important. I think the meteorological and hydrogeological indicators such as SPI and GRI, are more reliable for moderate regions with high precipitation and sallow aquifers. I look forward to receiving your valuable opinions about this matter.

Are we receiving necessary information for amply assessing the groundwater pollution potential?

OR

Are we biased towards the hydro-geological settings (that potentially decides the transport of pollutants)

than

the socioeconomic conditions and the anthropogenic activities (that potentially release the pollutants)?

The sand body on the river bed is 9 meters thick. It consists of medium and coarse sand. The stream course on the river changes course and hence direst pumping stations for irrigation are adversely affected. The base flow is the only alternative left for exploitation.

I am looking to obtain the K_fs of only the top 30cm of a beach profile and I am not sure which model to use.Ideally, I would like to use something more simplistic for ease of computation. would something general and  simplistic like the Philips (1956) two-term model work or should i use something more complex, like the Reynolds and Elrick (1990) two-ponding head approach. 

Thanks for your advice.

I am having difficulty understanding what in-situ variables i will need to measure to predict saturated hydraulic conductivity using the Philip's (1957) two-term model and a double-ring infiltrometer?

Rate infiltration Eqn. i(t)=1/2St^1/2+A 

Cumulative Infiltration Eqn. I(t)=St ^½+At 

Where S is sorptivity and A is dependent upon the soil properties as well as initial and boundary water contents.

what information do i need to gather to calculate A and S, and in turn, how do I calculate it?

Thanks for any help you may be able to provide,

Lee 

I want to know if it is possible to construct a 3D structural model for a certain area using "Midland Valley Move software" by utilizing boreholes only.

Suggest me drought monitoring through remote sensing and GIS with combination of Hydrogeology.

Thank you..................

I am a Congolese hydrogeologist. Groundwater resources of the DRC are unknown. I am making a database of existing Wells and borehole with hydrogeology data.