Welcome to PETGEM’s documentation!

PETGEM (Parallel Exascale Toolkit for Geophysical Electromagnetic Modeling) is an open-source software for large-scale 3D electromagnetic (EM) modeling. It implements a high-order edge finite element method on unstructured tetrahedral meshes, enabling accurate simulations for active-source EM problems in both forward modeling and inverse modeling (inversion).

Originally developed in Python, PETGEM has been refactored in C and integrated with PETSc to improve scalability on massively parallel architectures, memory efficiency, and mesh handling. These advances make PETGEM well suited for current and future exascale systems.

PETGEM has been successfully applied to subsurface exploration in oil & gas, geothermal reservoir characterization, and environmental EM surveys.

Key features

• High-order edge finite element method

• Forward modeling and inversion (L-BFGS with adjoint-state gradients)

• Unstructured tetrahedral mesh support (Gmsh)

• Parallel computing with MPI and PETSc

• Python bindings for pre- and post-processing

• Integration with performance analysis tools (Extrae)

More information

• PETGEM GitHub repository

• See our publication list at Publications

Getting started:

• Installation
  • Requirements
  • Docker installation
  • Makefile usage
  • Python helpers
• Quickstart
  • Prerequisites
  • Build
  • Run the canonical forward example
  • Using the unified dispatcher
  • Next steps
• Overview
  • Execution modes
  • Shared workflow

Forward modeling:

• Forward modeling
  • Workflow
• Forward modeling examples
  • Canonical CSEM example
  • Extrae profiling example

Inverse modeling:

• Inverse modeling
  • Workflow
• Inverse modeling examples
  • Canonical inversion example

Reference:

• Numerical formulation
  • Forward problem
  • Inverse problem
  • Conventions
• Data formats
  • Conductivity table (sigmas.txt)
  • Sources
  • Receivers (-receiver_filename)
  • Observed data (-observed_filename, inverse only)
  • Input bundle (-input_filename, default input.h5)
  • Responses file
• Mesh generation
  • Physical groups and material ids
  • Element sizing
  • Per-order meshes
  • Generating a mesh
  • VTK input
• Solver options and performance
  • Default solver configurations
  • Choosing a solver by polynomial order
  • Mesh resolution and the h-p tradeoff
  • Parallelism
• Troubleshooting
  • Build
  • Run
  • Documentation
• Python API
  • Preprocessing
  • Readers
• API Reference
  • Assembly module (assembly.h)
  • Common module (common.h)
  • Constants module (constants.h)
  • Grid module (grid.h)
  • Hvfem module (hvfem.h)
  • Inputs module (inputs.h)
  • Inversion module (inversion.h)
  • Io module (io.h)
  • Kernels module (kernels.h)
  • Postprocessing module (postprocessing.h)
  • Receiver_interp module (receiver_interp.h)
  • Solver module (solver.h)
  • Transmitter module (transmitter.h)
  • Version module (version.h)

Development:

• Testing
  • Layout
  • Running the tests
  • Environment variables
  • What the integration suite checks
• Contributing
  • Building
  • Code conventions
  • Documentation
  • Continuous integration
  • Testing

About:

• Publications
• Changelog
• Contact

Indices and tables

• Index

• Search Page