Basaltic lava flows, mainly aa type, fragmented in blocks with numerous cracked tumulus, longitudinally and transversally, from the eruptive fissure of Montaña Lobos, from the Pleistocene Era. Over these lava flows, there are hydromagmatic pyroclastic density currents from the hydromagmatic caldera. On the lower areas, closed endorheic depressions have developed de forming ephemeral, not very powerful, pools when it rains, and sandy-clay or muddy, not very powerful rain deposits build up and with abundant anthophora nests. On the north coast, there is El Jablito, an accumulation of folic and fine white sand of organogen origin (crushed marine shells), from the sea.
The main interest of the geosite is related to volcanology, although there are also geomorphological, sedimentary and paleontological factors. The contrast of shapes and colours make the Malpaís del Norte a spectacularly beautiful karst landscape.