And the answer, at least the very first one, is that there are no volcanoes in Cabo de Gata. Indeed, volcanic activity has ceased for about 7 million years ago (remember me propose a very instructive analogy to get a bit incomprehensible of the geologic time), and since then erosion has fulfilled its role.
Of course there are some nuances. Such is the case of the Cerro del Fraile, crowned with two andesitic domes with columnar jointing (which are listed as a geo-resource in the Andalusian geological heritage inventory). This hill, which of course was once a volcano, now is just what remains of it, and its morphology serves erosion criteria rather than their origin (not forgetting that the erosion and morphology are most of the times controlled by the presence of various rock types and geological structures). The dome would be the remains, partially eroded, of the last eruptive episode, which emplaced lava beneath the crater, and there it cooled and solidified. We must therefore think that the volcano's summit, the crowning of the crater, would be located several hundred meters above the current top height of 493 m. And surely the diameter of the mountain would be significantly higher than today presents.
But we should begin to differentiate between types of volcanic edifices, as if something is clear is that the current morphology of these mountains is also associated with the type of the original volcano. The 7 to 15 million years ago since the Cabo de Gata volcanism took place not equally affect a stratovolcano as the Cerro del Fraile, a caldera as the Rodalquilar or Majada Redonda ones, or a simple cinder cone. We should add that most of the best preserved volcanic structures in the area are protected at the top, either by limestone (from coral and fossilized remains of organisms that developed in a shallow sea in the final stages of volcanic activity), or by particularly resistant volcanic rocks, like lava flows or the El Frailes domes.
In coming issues we will discuss the different volcanic edifices related to the volcanoes of Cabo de Gata, other similar ones in various parts of the world, and the processes that lead to the formation of each. And we will start with the most spectacular of them, the caldera, the result of a huge eruption, and one of the most recognizable morphologies in volcanic landscapes.