on this part of the volcano. The fissure eruptions resulted in lava flowing from the fissure. There was also an eruption within the caldera. A second fissure opened lower down the slope in early June. Analysis of the lavas on Cerro Azul show a range of tholeiitic to alkalic basalts that are unlike the neighbouring Sierra Negra or Alcedo volcanoes. A study published in 2006 showed that there was continuous expansion of the volcano prior to and after the eruption in 1998. This expansion would have been due to the emplacement of magma into the magma chamber. Wildlife The species of Galapagos tortoise on the island is Geochelone vicina, this subspecies is dome-shelled and has an overlapping range with the species on the neighbouring Sierra Negra volcano, Geochelone guentheri, which is a saddle-backed tortoise. The Cerro Azul tortoises were not affected by the 2008 eruption, although the 1998 eruption did force the National Park authorities to move the tortoises by land and helicopter. Other tortoises were killed in that eruption, either from lava or associated fires. See also Volcanoes of the Galápagos Islands List of volcanoes in Ecuador References Azul Azul Volcanoes of the Galápagos Islands Polygenetic shield volcanoes Pleistocene shield volcanoes Holocene shield volcanoes