I climbed up Mount Teide back in the early 80s. It is quite surprising how hot the ground is there when you dig down a little... and that's from an alegedly dormant volcano.
Is it Gran Canaria that is in danger of falling to pieces?
We have a volcano here on Lanzarote called Timanfaya, where they take tourists and scrape a little of the gravel off the surface and then pick some up from only a few centimetres below the surface on a shovel, they put it into peoples' hands and most can't hold on to it. Nest they shove a bit of brush wood down a hole 2m deep and it catches fire from the heat down there and finally they pour a bucket of water down a bore hole 20m (might be 12m, can't remember) and it comes back up as a jet of steam. they also have a grill which sits above a fissure and the food is cooked from the heat rising from the fissure.
And the island which will fall into the sea is La Palma, it already has a great crack in it, I've been looking at houses in the hills myself!