(Within the framework of GEMex, a Horizon 2020 project (Grant Agreement No. 727550), we model the initial natural state of the super-hot reservoir system of Los Humeros. This is achieved by solving the porous flow and heat transport equations in a gridded, structural 3D model of Los Humeros using the SHEMAT-Suite (Simulator for Heat and Mass Transport) software (Rath et al., 2006, Clauser, 2003). Initially, we perform purely conductive simulations and check the simulated temperatures against the temperatures measured at the well bottoms. We tested several conductive scenarios to obtain an understanding of the pattern of the basal specific heat flow under the Los Humeros caldera complex.)