The islands of Gran Canaria and Tenerife appear to be registering geodynamic movement towards one another that could see the two meeting in a few million years' time.
Experts from the University of Seville and the Astronomy, Geodesy and Cartography Laboratory at the University of Cadiz have recently published an article in the Journal of Geodynamics, in which they analysed the behaviour of the geodynamic zone around the island of Tenerife.
Although the aim of the study was not to establish a shrinking of the area between the two islands, residual plate velocity indicating movement of Tenerife towards Gran Canaria was observed, and the scientists have subsequently suggested it be studied in the context of the entire Canary Islands archipelago.
"The amount of intraplate displacement between the islands of Tenerife and Gran Canaria can be measured in millimetres, therefore, given the distance between the two islands (approximately 64 km), they will not join for millions of years," explained Sevilla University professor Cristina Torrecillas.
What is actually being experienced is a gravitational subsidence or isostatic rebound after the series of minor earthquakes that rocked the Teide in 2004. This phenomenon has been detected thanks to data supplied by GPS stations dotted around the island of Tenerife, each measuring to the millimetre.
In addition, a widening of the northeastern fissure has been observed, possibly because of minute changes in a secondary fault line which splits Anaga mountain range in the island's centre.
After the Teide volcanic crisis in 2004, the decision was made to control the geodynamics of the island of Tenerife,and seven reference points were established around the island. Two of them were configured to provide constant observation, and the remainder have been consulted periodically at least twice a year since 2005. Since 2008, other public bodies have set up seven additional reference points with publicy accessible observation stations. Together, these two networks are known as the TEGETEIDE GNSS network and this latest study is based on its data.
"Vulcanology is a complex and multidisciplinary science, but it has been proven time and again that ground deformation in active zones generally precedes seismic or volcanic events. This technique was applied in the case of the recent eruption on the neighbouring island of El Hierro, but it wasn't until 2015 that a study was published in 'Science' magazine about predictive action of magnetic intrusions", explained Torrecillas.