Geothermal resources and present orogenic activity

Abstract

Some of the interesting zones of abnormally high heat flow show a characteristic position relative to young orogenic belts. Usually, orogenic fronts are combined with low heat flow values in the foreland and high heat flow behind the front. The idea that this might be connected with present orogenic activity to produce at least some of the high heat flow values measured till now, may be worth considering. Geothermal resources of economic interest may be expected where volcanic activity, heat conductivity of the crust, and orogenic heat concentration are working together. Young orogenic fronts still active distinguish themselves by strong negative gravity anomalies shifted outward in the foreland direction. The inner girdle of such active orogens is marked by backland volcanoes, violent or extinct, by large volumes of granitic material (if enclosed in the continental crust), and by regional metamorphism as an indication of intensified heat flow. Such supposed zones with present orogenically intensified heat flow behind the active orogenic fronts round the world, are shown by a series of Figures (1–8).