5.1.1. Synthetic Case

To examine the temperature effect of salt, we made a simple model with a vertical salt plug over a thin salt layer (Figure 15). No thinning of the salt layer and no salt withdrawal with increased basin subsidence is used in these models. The top of the model is kept at surface at all time steps. All sediments were defined as shale.

**Figure 15.** Temperature effect of salt in the synthetic simple model. B) Model without salt diapir, (**<sup>a</sup>**,**b**) with salt diapir (orange). (**c**) Difference in thermal conductivity between the two models, (**d**) temperature difference between the two models. Grey to blue colors: Colder sediments in salt diapir model. Brown to red colors: Higher temperature in diapir model.

The thermal conductivity of salt is strongly temperature dependent, described by a temperature correction factor α. This factor is used in the following manor to correct thermal conductivity values (equation modified from Reference [26]):

$$
\lambda = \lambda ref \frac{\lceil 1 \rceil}{\lfloor 1 + aT \rfloor}
$$

where:


Figure 15 shows the input profile with and without salt and the resulting temperature effects. The resulting effect on temperature is clearly seen in the temperature difference plot in Figure 15d where the model with salt diapir has significantly higher temperatures in the sediments above the top of the salt structure (brown to red colors), and colder sediments (grey to blue colors) at depth relative to the case without the salt diapir. These simple models demonstrate that the conductivity difference between salt and sediments play an important role in temperature distribution around salt structures.
