One of the basic structures of the volcanic islands, is known as dorsal triple, first described for the island of Hawaii, consists of three volcanic alignments separated from each other 120 °. In this installment of the blog try to explain the appropriateness of calling this structure "tripod" based on similarities in behavior. Canary
There are 3 of these ridges being the most evolved of Tenerife (Teno and Anaga without), while La Palma and El Hierro are earlier stages of evolution, in that order.
In the picture 1 shows a small photo tripod, next to which it has drawn the outline of the island of Tenerife, and on the compression waves propagating from north of the island, red orientation (theoretical) of the dikes on the island.
As we saw in a previous issue concerning the triangular islands, once the wave front from the Atlantic Ridge reached the islands, crossing an area that acts like a slot Huygens (the width of a Huygens slot is small but significantly greater than the wavelength passing through it).
An elevation on the ocean floor, a change of density in the cortex, may function as a slot, ie to propagate through it to the compression wave is likely to lose its energy which is absorbed by the rock along the pattern defined by the interference wave in the slot, hence the typical form of these islands and the orientation of the volcanic dikes (which correspond to the places where the interference suffered positive reinforcement, the accumulated energy)
As we see the silhouette of the island fairly well to the small tripod, this similarity goes beyond. Like the tripod triangular island has its highest point at the junction of its legs, dorsal, has this point we will call summit here. This point coincides with the glens Tenerife and the Teide highest point or the Caldera and the Roque de los boys in Palma.
It should be noted, that with a loss of weight on top (eg erosion in the Caldera) the tripod may experience a rise in response, thus explaining underwater rocks found in the boiler to 500 m Taburiente high and possibly subsequent volcanism in the area due to the necessary rehabilitation of the tripod gets a lift (if the downturn in the volcanic caldera Taburiente)
While weight loss can lead to elevation of the summit, the mechanism principal elevation of this is the constant pressure from the ridge, which also produces General volcanism throughout the structure. In a next installment
see how the peculiar orientation of the dikes, triangular islands coupled with the ability to adjust in height depending on the weight bearing structure, has important implications in the evolution of the structures of the islands, mainly because called gravitational subsidence, of which there are three in the archipelago, the valleys of La Orotava and Guimar Ariane in increasing order of seniority
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