fem2geo 0.1.3

Physics-based Modeling to Structural Geology and Seismology

fem2geo

Physics-Based Modeling to Structural Geology and Seismology

A Python library for structural geology and seismology analyses on outputs from finite element (FEM) or boundary element (BEM) models

fem2geo bridges numerical simulations and field observations: it loads model outputs, extracts regions of interest, computes geomechanical variables, and produces publication-quality stereonet figures.

Key capabilities:

• Load and normalise FEM/BEM simulation outputs (VTK/VTU) via a flexible solver schema system
• Extract spatial subsets (spheres, bounding boxes) from large models
• Reconstruct stress tensors and compute volume-weighted average stress, principal directions, and stress invariants
• Slip and dilation tendency analysis on stereonets
• Compare multiple model realisations at the same location
• Run analyses from a YAML config file with sensible defaults and optional customisation

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Table of Contents

• Installation
• Run
• Tutorials
• Documentation
• Roadmap / Known Issues
• Contributing
• License

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Installation

Latest version

sudo apt install git python3-pip python3-venv
git clone https://github.com/pabloitu/fem2geo
cd fem2geo
python3 -m venv venv
source venv/bin/activate
pip install -e .

Stable version (from PyPI)

python3 -m venv venv
source venv/bin/activate
pip install fem2geo

Tutorials are not included in the PyPI package. Download them separately:

fem2geo download-tutorials

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Run

Each tutorial folder contains a config.yaml for the basic case and a config_advanced.yaml with full plot customisation. Run either with:

cd tutorials/1_probing_model
fem2geo config.yaml
fem2geo config_advanced.yaml

The job key in the config selects the analysis. Currently supported jobs:

Job	Description
principal_directions	Stereonet of average (and optional cell-level) principal stress directions for one or multiple models
tendency_plot	Slip and/or dilation tendency contour with average principal directions overlaid

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Tutorials

#	Folder	Job	Description
1	1_probing_model	principal_directions	Probe average stress state at a location in a single model
2	2_model_comparison	principal_directions	Compare principal stress directions across multiple models
3	3_structural_data	compare_structural	Overlay field structural measurements on model predictions
4	4_tendency_plot	tendency_plot	Slip and dilation tendency with average directions

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Roadmap / Known Issues

• Borehole module: sample model variables along a borehole trajectory
• Seismic catalog module: import focal mechanisms and compare with model stress orientations
• Raster module: compare model plan-view outputs with surface observations
• Inversion module: find the model configuration that best fits a dataset
• Schema: add a lithostatic flag to mark whether outputs include lithostatic pressure
• Stress reconstruction warning fires on every stress access — should fire once per instance