Heat flow and temperature gradient data from Spain.

Abstract

The results of temperature loggings in numerous holes were used to calculate geothermal gradients and to estimate heat flow. On the basis of these data a preliminary heat flow map of Spain is proposed. The mean land heat flow value amounts to 82mWm-2 in the iberian peninsula and reaches 99 mWm-2 in the surrounding marine areas, which in both cases is considerably higher than the mean European heat flow. There is a negative correlation between heat flow and crustral thickness. The heat flow generally increases from the central part of the peninsula (82 mWm-2) toward the Mediterranean coast (95 mWm-2), while the crustral thickness decreases from 36 km near Meseta to 27 km in the coastal area. The thinner the crust, the greater is the upper mantle heat flow contribution. Similarly, the calculated Moho temperatures increase from 720oC in the Meseta region to 880oC beneath Cartagena. r-Author