Milos

Geography & Climate

Milos is located in Greece, within the Hellenic Volcanic Arc of the broader European Volcanic Regions. Situated at 36.70° N, 24.44° E in the Northern Hemisphere, the volcano lies within a temperate climate zone. With a summit elevation of 751 meters above sea level, Milos is a moderately sized peak that remains accessible to hikers and researchers for much of the year. The volcanic landform is characterized as a composite, which describes the physical shape and structure of the volcanic edifice as observed from the surface.

Geological Context

Milos sits in a subduction zone, where one tectonic plate dives beneath another, creating intense heat and pressure that generates magma. Subduction zones are responsible for many of the world's most explosive volcanoes and deadliest eruptions. For communities in Greece near Milos, this tectonic setting means the volcano is capable of producing powerful explosive eruptions, pyroclastic flows, and lahars that can threaten populated areas within tens of kilometers of the summit. The dominant rock type is rhyolite, a silica-rich volcanic rock associated with highly viscous magma. Rhyolitic eruptions can be extremely explosive and are responsible for some of the largest volcanic events in Earth's history, including supervolcanic caldera-forming eruptions. The high silica content traps dissolved gases, building enormous pressure that can lead to catastrophic explosive releases.

Eruption History Summary

Milos has 1 recorded eruption in the geological database, spanning from 140 CE to 140 CE. The most powerful recorded event was a gentle, effusive event in 140 CE, reaching VEI 1 on the Volcanic Explosivity Index.

GVP Reference Summary

Mílos and adjacent small islands have grown from submarine and subaerial volcanism that initially was dominantly andesitic and basaltic, but ended with predominately rhyolitic eruptions. The oldest volcanic rocks are Pliocene submarine rhyolitic pyroclastic-flow deposits overlying basement metamorphic and sedimentary rocks. The latest activity during the late Pleistocene was concentrated in the eastern half of the low, U-shaped Mílos Island, forming lava domes and phreatic explosion craters, and on Antimílos Island to the NW, where a composite volcano was constructed. The youngest magmatic eruptions took place about 90,000 years ago, but phreatic explosions, commonly producing overlapping craters rarely more than 1 km in diameter, continued from late-Pleistocene to Recent times. A lahar deposit in SE Mílos, east of Fyriplaka tuff ring, buried walls of a Roman harbor town and overlies a coarse ash layer, and was considered to originate from a small phreatic explosion through basement rocks.

— Smithsonian Institution, Global Volcanism Program