**List of Figures**

- 1. Schematic description of the rotation and non-rotation simulations used in this study
- 2. Comparison of non-rotation simulation with the non-rotation model as described by Bell (1985)
- 3. Movies of the non-rotation (a) and rotation (b) models of spiral formation
- 4. Movies showing the progressive development of spiral inclusion trails according to both the rotation and non-rotation models of spiral formation
- 5. Comparison of the 3D geometry of the rotation and non-rotation spiral simulations
- 6. Serial 2D slices through the final spiral geometries of the rotation and non-rotation simulations
- 7. The effect of varying theta (angle between pre-deformation matrix foliation and shear plane) on spiral inclusion trail geometry
- 8. The spiral geometries that result from simulations with varying rates of sphere growth
- 9. The effect on spiral geometry of varying the degree of coupling between the sphere and matrix
- 10. The effect on spiral geometry of varying the proportion of simple and pure shear deformation within the matrix