(a) 0 years
(b) 20,000 years
(c) 125,000 years
Figure 6: Temperature field resulting from the transient natural state simulation. The three wells (RAI01, Alfina015, and Alfina002; see also Figure 1), for which the available temperature logs were used to identify the reservoir present-day thermal state, are shown. Three different simulation times are presented: (a) 0 years, initial temperature field equal to the average earth gradient of 0.3°C/10 m; (b) 20,000 years, beginning of the oscillating multicellular convective regime confined in the reservoir units; and (c) 125,000 years, best-fitting time step resulting in a good match between simulated and real thermometric data for the 3 evaluated wells (see Figure 7).