The basalt organs of Mirabel

The basaltic organs at Mirabel in the Ardèche are the result of geological formations created by the cooling of volcanic lava.

The Coiron massif, a volcanic plateau

The Coiron massif is a volcanic plateau formed by ancient lava flows dating back around 8 million years. The rocks produced by these cooled lava flows are very compact and resistant to erosion. The result is that the lava flows, which were once in a low-lying position, are now, after erosion of the surrounding soil, in a high-lying position. This is what is known as an inverted relief, in that the plateaus we see today were once the valley bottoms through which the lava flowed.

The basaltic organs of Mirabel

Volcanic eruptions here were essentially fissural, with the lava flowing through cracks. Most of the time, the flows are in two parts, with the lower part containing some very beautiful basalt prisms known as basaltic organs, with their characteristic hexagonal shape. Note that these basaltic organs formed during cooling are always perpendicular to the direction of the lava flow.

Itinerary Mas de la Fontenette – Mirabel basaltic flows

The basaltic flows of Mirabel are less than an hour’s drive from Mas de la Fontenette. Our 4-star gite with heated swimming pool also has a wellness area (Jacuzzi, sauna, exercise bike, table football and pétanque).