Figure 8From: Diffuse CO2 degassing and volcanic activity at Cape Verde islands, West Africa Relationship between soil CO 2 efflux peak values (×background) and the average 3 He/ 4 He ratio from Cape Verde archipelago. Horizontal bars represents the minimum and maximum 3He/4He ratio measured by Heilweil et al. (2009), in the case of San Antão and São Nicolau (assumed to be similar for São Vicente) and this work for Fogo and Brava islands.Back to article page