The island of El Hierro in the Spanish Canary Islands is bracing itself for a possible volcanic eruption. Situated in the Atlantic Ocean off the west coast of Africa, the Canary Islands are all volcanic, but there has been no volcanic activity on El Hierro since 1793. However, a series of small earthquakes have been registered by sensors in the past two months and a quake of grade 3 on the Richter Scale registered last Thursday have caused the threat of volcanic activity to be raised from green to yellow for the first time in recent history. Saturday produced another stronger tremor of 3.4 on the Richter scale which was felt all over the island. Speaking to the El Pais newspaper, volcanologist, Juan Carlos Carracedo admitted an eruption on El Hierro would not be a major surprise. \"It is the youngest of the Canary Islands,\" he explained. \"There is a ball of magma which is rising to the surface and it is stationed at the limit of the earth\'s crust. At the moment we do not know if that ball of magna will break the crust and cause an eruption.\" Rather than having one large crater, the volcano on el Hierro consists of around 250 small craters. \"Any eruption would form cones on the high zones of the island and lava flows which would flow to the sea, although they would do so at a speed that would be slow enough for the population to be evacuated. It is something that could happen in days, weeks or months,\" said Carracedo. El Hierro currently has a population of around 10,000 and regional government officials have begun informing them of evacuation protocols in case the worst should happen. The last volcanic eruption in the Canary Islands took place on the island of La Palma in 1971, while the mainland town of Lorca was devastated by an earthquake of 5.2 on the Richter scale in May this year.