A collection of notebooks that use the electromagnetics (EM) module of SimPEG. Many of these notebooks reproduce examples from EM GeoSci, an open source “textbook” on applied electromagnetics.

If you build upon these notebooks in your work, please cite:

- (Cockett et al., 2015):
*SimPEG: An open source framework for simulation and gradient based parameter estimation in geophysical applications* - (Heagy et al., 2016):
*A framework for simulation and inversion in electromagnetics*

If you have feedback, we would like to hear from you!

**EM Fundamentals | Inverting Field Data | MT Tutorial | Additional Notebooks**

These notebooks walk through using SimPEG for conducting a TDEM and FDEM soundings over a sphere. They use the cylindrically symmetric mesh for the forward modelling

These notebooks walk through inverting a single sounding of airborne EM data collected in Australia.

These notebooks were originall published in The Leading Edge

```
Seogi Kang , Lindsey J. Heagy , Rowan Cockett , and Douglas W. Oldenburg (2017). ”Exploring nonlinear inversions: A 1D magnetotelluric example.” The Leading Edge, 36(8), 696–699.
```

There are 5 notebooks in this tutorial - we wrote them starting from discretizing the governing equations for the Magnetotelluric Problem, running a forward simulation and exploring an example of non-uniqueness, and performing the inversion. Although this is a natural order in terms of building the pieces, you do not need to work through them in order, each notebook is self-contained and has links to others where appropriate.

- 1_MT1D_NumericalSetup: discretize and solve the 1D MT equations
- 2_MT1D_ForwardModellingAndNonuniqueness: run the forward simulation and explore an example of non-uniqueness
- 3_MT1D_5layer_inversion: run inversions for a 5 layer model and explore the impacts of choosing a trade-off parameter $\beta$, and changing the regularization parameters smoothness and smallness ($\alpha_s$ and $\alpha_z$).

There are also 2 "appendix" notebooks

- Appendix_A_MT1D_Sensitivity: derive and test the sensitivity
- Appendix_B_MT1D_tests: demonstrates how we test the code

From the menu, select `cell`

, `run all`

, or run each individual cell using `shift + enter`

If you want to start with a clean slate, restart the Kernel either by going to the top, clicking on Kernel: Restart, or by "esc + 00" (if you do this, you will need to re-run the following block of code before running any other cells in the notebook)

For more information on running Jupyter notebooks, see the Jupyter Documentation

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