1887

Abstract

Summary

The heat flow density and temperature data obtained in part of the South Portuguese Zone in Portugal are analyzed in this work. Part of the Iberian Pyrite Belt is located in the region studied. The heat flow values are higher than average values found in continental regions and the excess of heat found can not be provided by radioactivity sources in the region like uranium, thorium and potassium. The excess of heat is obtained considering that the anomalous sources of heat are located in a uniform layer with a thickness of 6 Km. The difference between the average value of heat sources and the radioactivity sources (D-A) is directly related with the heat flow values measured in the region. High thermal gradient values can be found in neighboring regions with low thermal conductivity values suggesting the existence of lateral heat transfer. It is suggested that the excess of heat is due to chemical reactions involving oxidation of pyrite ores abundant in the region. At the end a question is made. Why not use the heat flow in the detection of pyrite bodies in the region ?

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/content/papers/10.3997/2214-4609.201802748
2018-09-09
2024-04-25
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References

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