These talks will be self-contained presentations of mathematical concepts and theorems. They are intended to be accessible to all mathematics students.

The Earth is riddled with faults at every length scale from the size of the plates down. If we want to build a model Earth we'll need to take into account the big, important faults that run through the model, and also the ones at a scale too small to include individually. Then we need to worry about how the two scales interact. To put all this in context, I will be giving a simple overview of how the Earth works, how model Earths work, and how we are trying to deal with faults.