First heat flow density assessments in Cuba

Abstract

The first determinations of heat flow density in Cuba are reported. Precise temperature loggings were carried out in 12 holes in the western and central parts of Cuba. Along the northwestern shore, the mean temperature gradient ranges from 14–16 mK/m in the Pinar del Rio province and 18–22 mK/m east of Habana to 30 mK/m in northern Matanzas. In the Central Basin it ranges from 23–24 mK/m west of Ciego de Avila to 28–39 mK/m east of Sancti Spiritus. Rock samples for laboratory determination of thermal conductivity could be collected only from two holes in Pinar del Rio; their mean conductivity amounts to 4.1 W m −1 K −1. From other holes no core samples were available and characteristic rocks were collected from surface outcrops in the vicinity of each hole. The measured conductivity ranges from 0.8 to 3.0 W m −1 K −1. Heat flow density assessments revealed very low heat flow near Habana and south of Varadero (30–40 mW m −2) and relatively higher but still rather subnormal values in Pinar del Rio (60 mW m −2) and in the Central Basin (50–65 mW m −2). The generally low heat flow density found in western and central parts of the island thus seems to agree well with the results of marine observations in surrounding areas reported by other authors.