March 22, 2024

Simple example of ion exchange modeling with Phreeqc and Aquifer App - Tutorial

March 22, 2024/ Saul Montoya

An example that demonstrates the Phreeqc and Aquifer App capabilities to model ion exchange. This example uses the cation ion exchange approach where only the EXCHANGE keyword is used because EXCHANGE_MASTER_SPECIES and EXCHANGE_SPECIES are included in phreeqc.dat database. The model output is parsed as charts and tables and the solution composition and description are calculated and compared before and after the exchange.

March 21, 2024

A Python class to export Modflow 2005 model 3D geometry and parameters to Vtk - Tutorial

March 21, 2024/ Saul Montoya

Generating 3D visualizations of groundwater models is essential to analyze the flow regime, perform quality checks and see the interaction of the groundwater body with external factors / boundary conditions. The Flopy library has tools to export the parameters, boundary conditions and results that we have modified and compiled within a Python class. The use of this class allows the generation of Vtk files on a friendly way and in few steps. The tutorial also includes a representation of the parameters generated in ParaView.

February 12, 2024

Seawater speciation modeling on cloud with Aquifer App and Phreeqc - Tutorial

February 12, 2024/ Saul Montoya

No more installations, no more database link up, no more raw text data as model output. Aquifer App now can run Phreeqc with great tools for the geochemical model setup, database selection and tables / graphics for the different simulation components.

This applied example calculates the distribution of aqueous species in seawater and the saturation state of seawater relative to a set of minerals and is based on the Example 1 of the USGS Phreeqc example documentation.

January 24, 2024

Sensibility analysis of transient pumping test with MODFLOW-6, Flopy and SALib - Tutorial

January 24, 2024/ Saul Montoya

This tutorial covers the whole procedure to perform a sensitivity analysis over a 72 hour pumping test plus recovery on the hydraulic response in an observation piezometer located at 11 meters from the well. the Since the study case it’s a transient model the sensitivities will vary over time and stage of pumping/recovery.

January 11, 2024

Geological modeling of sedimentary layers from geospatial rasters with Python and Gempy - Tutorial

January 11, 2024/ Saul Montoya

Based on a coupled workflow on QGIS and Python it is possible to extract the required information for a Gempy model and run it for defined voxel sizes. This tutorial covers the whole procedure of spatial data preparation, data preprocessing in defined formats and geological modeling with Python and Gempy.

January 03, 2024

Theis solution for pumping test interpretation in confined aquifers in Aquifer App - Tutorial

January 03, 2024/ Saul Montoya

Theis (1935) developed a method to estimate values of T and S from pumping test data. Time and drawdown data are measured in an observation well and then matched to the Theis curve. Aquifer App, a web framework for applications in hydrogeology now has a tool for the interpretation of the Hydraulic Transmissivity based on the Theis solution. This is a perfect tool to parametrize homogeneous and confined aquifers on transient state flow conditions.

January 02, 2024

A Python class to export Modflow 6 model 3D geometry and data to Vtk - Tutorial

January 02, 2024/ Saul Montoya

December 19, 2023

How to create a Schoeller plot online with Aquifer App - Tutorial

December 19, 2023/ Saul Montoya

We present our own webapp for the representation of the Piper Diagram, Stiff Diagram and Scholler Diagram. The webapp was developed in Python Django and it is entirely free for everyone. The main objective behind this webapp was to develop a user friendly and minimum requirement tool to create these water quality / hidrogeochemical diagrams. The video tutorial shows the complete procedure to update the working file and then generate the diagrams.

December 14, 2023

Thiem steady-state solution for confined aquifers in Aquifer App - Tutorial

December 14, 2023/ Saul Montoya

Aquifer App, a web framework for application in hydrogeology now has a tool for the interpretation of the Hydraulic Transmissivity based on the Thiem solution. This is a perfect tool to parametrize homogeneous and confined aquifers on steady state flow conditions.

June 12, 2023

How to install the geological Python library Gempy in Windows with WSL - Tutorial

June 12, 2023/ Saul Montoya

Gempy is an open-source library for modeling geology written in Python. The library is capable of creating complex 3D geological models including structures, fault networks, and unconformities and it can be coupled with uncertainty analysis.

This tutorial is developed under a Ubuntu 20.04.2 image installed from the Windows Store and covers all the steps to setup the user, install core packages, install Python packages and set up local paths to have a complete Gempy enviroment running under Jupyter lab.

February 02, 2023

Tupac Cloud T.2: Improved 2D head visualization in Tupac Cloud

February 02, 2023/ Saul Montoya

Lastest developement in Tupac Cloud for the representation of head as contours and color grid. Both representations have a colorbar and title related to selected layer. Objects as boundary conditions and model mesh can be represented on the plots.

July 21, 2022

3D visualization of voronoi gridded models with Model Viewer for Modflow 6 - Tutorial

July 21, 2022/ Saul Montoya

Model Viewer for Modflow 6 was launched in April 2022 and it is a version of Model Viewer customized to display the features, grid and results of MODFLOW 6 models. We have done an applied case for the visualization of a MODFLOW 6 DISV model that has a voronoi mesh. The tutorial covers the steps to visualize the model grid lines, grid shell, isosurfaces, color grid, flow directions among other visualization options.

June 09, 2022

Are hydrogeologists / numerical modelers forbidden from cloud services?

June 09, 2022/ Saul Montoya

In the semantic space the forbidden word is related to refuse to allow, and thus can create a controversy with the freedom of hydrogeologist / numerical modelers to choose whichever tool that can make the work done or the simulation run. However we as specialists in one part of the dynamics of the subsurface are conscious that solutions can not and must not be evaluated by single criteria.

December 01, 2021

Applied case of hydrogeological conceptual modeling on a hillslope area with QGIS

December 01, 2021/ Saul Montoya

In order to understand the relationship between groundwater flow and slope stability, a study area over a hotspot in the US. Landslide Inventory was selected. The geology, groundwater wells, elevation, and climate conditions were reviewed to develop a hydrogeological conceptual model that will be the basis for a numerical model of the groundwater flow regime. This webinar deals with the review of available spatial data related to the groundwater flow regime on a hillslope area at Mukilteo city, Washington, US. Information from geology, meteorology, observation data and boundary conditions will be discussed in a QGIS session with regards to the construction of a groundwater numerical model in MODFLOW.

November 08, 2021

Two open geological modeling softwares that you should know about

November 08, 2021/ Saul Montoya

For geologists, hydrogeologists, geostatistics, petroleum engineers, and other related professionals the choice for 3D geological modeling software was related to expensive and restrictive software that was in fact a “de facto” choice in several companies and institutions.

Although it is a choice of any company or professional to select the software anyone will use to model the geological units, a great gap subsides (using a geological term) on the use of this expensive software. If the software is expensive, how expensive will it be to get trained on this software? If few people have skills with certain software, how easy would it be to change to another software? How people can assess the quality of one software if they have no full capability on managing several softwares. As you have seen, restrictions on the licenses lead to these subsiding gaps, faults on quality, and an intrusion of professional ignorance.

October 25, 2021

How long does it take to develop a groundwater model for my research project / master thesis?

October 25, 2021/ Saul Montoya

Developing a hydrogeological research project that considers groundwater modeling for a bachelor thesis or a master thesis requires you to take into consideration several topics, such as input data, hydrogeological knowledge and time to learn the software in order to provide a numerical simulation that reaches the objectives of your research project.

Learning a software for groundwater modeling should be easy as developing some tutorials and playing around with your own data; however it is not that easy since it involves the review of lots of documentation, have strong knowledge in hydrogeology and numerical modeling and deal with uncertainties and numerical unconvergences.

October 04, 2021

New website! MODFLOW Questions and Answers: ask anything on groundwater modeling

October 04, 2021/ Saul Montoya

Until now we had limited options to provide specific support in groundwater modeling. We know that modeling requires the review of extensive documentation and practical work with the software and sometimes or most times we don't have the time to sort things out.

September 17, 2021

The Groundwater Project as a source of free books in basic and applied hydrogeology

September 17, 2021/ Saul Montoya

We usually received some emails and messages regarding basic or reference books and publications in Hydrogeology and we didn't have any reference of free and high quality material until we knew about the Groundwater Project. It´s true that we found the project website some months ago, but it was at the latest IAH conference where we had a presentation with a complete overview of the program.

August 23, 2021

What to do when your MODFLOW MT3D contaminant plume doesn’t migrate?

August 23, 2021/ Saul Montoya

This is a problem that every hydrogeologist - numerical modeler has faced many times over his/her professional career independently from the theoretical background and skills with the code, graphical user interface or Python library.

We don’t know why groundwater “flows” and a contaminant plume “migrates” when both move on the aquifer system. After you construct you model geometry, setup the flow boundary condition, specify your transport package, define your contaminant sources, run your MODFLOW flow model and then run your MT3D model (or even your MT3DMS model) you will find that there is no plume, none, nada, nichts.

August 18, 2021

Open source groundwater software besides MODFLOW - Updated July 2023

August 18, 2021/ Saul Montoya

A special concern arises from the gap between the stage of development of open source groundwater software and the actual capabilities of the common groundwater modelers (we mean, the main group of modelers). Even though we are passionate about software we don’t find the time or the right momentum to have a real experience with those codes.

From our research, we have listed the top open source groundwater software with a brief summary of the capabilities and useful links. We have to mention that there are some packages that can simulate groundwater flow in software like OpenFoam; however, those variants are not listed here.

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