The island of São Vicente has the most abundant carbonatite outcrops in the Cape Verde Islands. A field survey of the main outcrops has shown that they consist of extrusive carbonatites, carbonatite dykes and small apophyses of intrusive carbonatite. These outcrops are spatially related to nephelinites. The compositions of the extrusive carbonatites and dykes plot close to, and within, the magnesiocarbonatite field. In contrast, the intrusive carbonatites are calciocarbonatites, with similar average strontium contents to those of extrusive carbonatites and dykes (around 4000 ppm), but remarkably low barium, niobium and total rare earth element concentrations. Whole-rock geochemistry indicates a strong affinity between the nephelinites and intrusive carbonatites, such that the latter could represent fractionation products of the same parental magma. This is in agreement with radiogenic isotope geochemistry, which shows a very restricted range of compositions in the Sr, Nd and Pb systems. Fractionation from a common parental magma occurred in two main steps: high-temperature nephelinite crystallization and high-temperature carbonatite immiscibility. The carbonatitic melts crystallized in two different environments, as follows: (1) a shallow intrusive environment, giving rise to the early calciocarbonatite cumulates; and (2) a vapour-dominated, extrusive environment, producing the later magnesiocarbonatites.

Zr-rich pyrochlore crystals in carbonatite from San Vicente (Cape Verdes Islands) show cryptic, concentric and rhythmic chemical zonation with Ca increasing and Ti, U and Zr decreasing towards the rims. In one carbonatite, taken from the Camile dyke, previously undocumented cryptic sector zonation of Ti, U and Zr is also observed in these crystals. The chemical variation is investigated by wavelength-dispersive electron microprobe, with both single spot and crystal map analyses.

The concentric and rhythmic zonation, marked by element substitution, was generated by magma heterogeneity and/or element diffusion kinetics, but it is suggested that the sector zonation, marked by differential site substitution, was governed by protosite variation between octahedral and cubic faces.

The grouper Cephalopholis taeniops is a carnivorous fish of the Cape Verde coastal marine ecosystem. Nothing is known regarding the age and growth of this epinephelid. In this study, the age and growth of C. taeniops was investigated by annual growth increment counts from 2804 specimens (7–51 cm total length) collected between January 2005 and December 2011. Whole otoliths underestimated the age indicated in sections by approximately 70%; therefore, sectioned otoliths were used in this study. A year's growth was represented by one opaque and one translucent ring. There was no apparent time lag from the start of the increase in the seawater temperature and the beginning of the formation of the opaque ring. The formation of the translucent rings coincided with a decrease in surface seawater temperature. Cephalopholis taeniops is a slow-growing and long-lived species, with ages of up to 20 years recorded. The seasonalized von Bertalanffy growth function was the best fitted among the four models tested, with an Akaike weight higher than 0.99. Growth was described by the seasonalized von Bertalanffy growth function as follows: L∞ = 54.26 cm, k = 0.135 year−1, t0 = −0.853 year, C = 0.439 and ts = 0.667.