*3.2. Restoration Methods*

Di fferent fault restoration methods cause di fferent basin geometries. It is of interest to explore what e ffect these di fferent geometries have on the resulting basin temperatures. In addition to vertical shear, we have therefore tested the basin reconstruction for 10◦ antithetic and synthetic shear, 20◦ and 30◦ antithetic shear and a case without fault reconstruction (Table 1). Basin reconstruction without fault restoration was done by moving the hanging wall section vertically up such that the timeline split by the fault zone is horizontally connected. This process gives no lateral mass movements of the basin. Vertical simple shear modeling was, as mentioned in the method section, done by BMT, while the alternative fault reconstructions were performed with Move. Antithetic simple shear results in a wider basin (Figure 2) and the larger the angle, the wider the basin. Synthetic simple shear results in a narrower basin (Figures 2 and 14) relative to the other methods. Vertical simple shear falls in between these two, while basin reconstruction without fault restoration results in a geometry which is quite di fferent from the other restored scenarios. Figure 14 shows the resulting geometries of the fault plane and top and bottom basement after fault slip of the six tested reconstruction methods. The basins with non-restored fault and restored by 10◦ synthetic inclined shear (purple and green line respectively, Figure 14) result in the shallowest hanging wall and top basement.

**Figure 14.** Resulting basin geometries after fault slip with the tested fault restoration methods. The di fferent colored lines represent the resulting geometry of fault plane and Top and Bottom Basement after fault is restored by the six tested restoration methods. dg = degrees.

The geometry variations resulting from the tested restoration methods involve varying footwall and hanging wall area and burial depth, which result in di fferences in the thermal calculations, especially in the footwall section. Therefore, the thermal di fferences between them are concentrated in the footwall part of the basin at the time of fault slip (Figure 15). Figure 15c shows that the temperatures prior to fault slip show a larger di fference on the footwall side compared to the hanging wall side. The comparison between the non-restored basin to basin restored by 30◦ antithetic shear, shows the largest area with thermal di fferences (Figure 15a), while the thermal di fferences between verticallyand non-restored basins are the most pronounced (Figure 15b). Although the thermal di fferences do not last long, ~1 Myr, such temperature di fferences might play a role concerning timing of generation and ultimately migration of hydrocarbons. For this particular case, the modeled thermal di fferences result in up to 40% maturation di fference of the potential organic matter in a limited time and area of the footwall section (not shown here). All the tested restoration methods require approximately 10 Myr to achieve a steady state after fault slip. We therefore conclude that the tested restoration methods do not lead to large di fferences in time needed for the basins to achieve steady state. However,

temperature differences due to different restoration methods may lead to temperature variations that might influence the maturation calculations.

**Figure 15.** (**a**) Temperature difference between a scenario restored with 30 degrees antithetic inclined shear, compared to a scenario with non-restored fault. (**b**) Temperature difference for a scenario restored with vertical shear compared to a scenario with non-restored fault. (**c**) Temperature point plot from foot wall (left) and hanging wall (right) in the two points indicated in (**b**).
