Ponta do Topo
Ponta do Topo and the entire west region of São Jorge constitute the island’s oldest area, which geological formations, predominantly basaltic lava flows, date from 1.32 million years ago. This age is, for instance, translated into the intense alteration of rocky formations present at Cais do Topo, visible due to the ball disjunction and sandy areas of the lava flows and in the peculiar shapes due to coastal erosion. Cabeço da Forca (one of the ten slag cones with morphological expression at the island’s East area) is cut by the cliff and shows its internal structure, including the associated Philonian net. Despite the high degree of alteration in the slabs, the pore texture of the basaltic rock is still perceptible, with abundant peroxin, olivine and plagioclase phenocrystals. The Topo Islander, with a flat surface, was formed from basalt and tuffs from the Topo’s Volcanic Complex, separated from the island, at an approximate distance of 400 meters, due to erosion. This geosite has regional relevance and scientific, educational and geo-touristic interest.