[1] The Reunion hotspot that formed the Deccan Traps also produced the Chagos-Laccadive Ridge and the Mascarene Plateau and plays a role in the geology of Mauritius and Rodriguez Island.
In 1981, geologists suggested that volcanism at Piton des Neiges may be closely linked to regional structural geology.
The main point of eruptive activity is associated with rift zone strike-slip faults and dike swarms around the mountain indicate cauldron subsidence.
Structural characteristics help to explain the dramatic erosion of the central caldera, which collapsed due to graben formation.
When cooled, Piton de la Fournaise lavas form basalt enriched in labradorite with almost no olivine.