Nemo Peak

Geography & Climate

Nemo Peak is located in Russia, within the Kuril Volcanic Arc of the broader Northwestern Pacific Volcanic Regions. Situated at 49.57° N, 154.81° E in the Northern Hemisphere, the volcano lies within a temperate climate zone. With a summit elevation of 1,018 meters above sea level, Nemo Peak is a moderately sized peak that remains accessible to hikers and researchers for much of the year. The volcanic landform is characterized as a caldera, which describes the physical shape and structure of the volcanic edifice as observed from the surface.

Geological Context

Nemo Peak 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 Russia near Nemo Peak, 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 andesite / basaltic andesite, a dark, fine-grained volcanic rock that forms from rapidly cooling, low-viscosity lava. Basaltic eruptions tend to be less explosive and produce fluid lava flows that can travel long distances. While less immediately dangerous than explosive eruptions, basaltic lava flows can destroy structures and infrastructure in their path, and volcanic gases released during these eruptions can affect air quality over a wide area.

Eruption History Summary

Nemo Peak has 12 recorded eruptions in the geological database, spanning from 7550 BCE to 1938 CE. The most powerful recorded event was an explosive event producing ash plumes up to several kilometers in 1938 CE, reaching VEI 2 on the Volcanic Explosivity Index. This level of eruptive frequency indicates a persistently active volcanic system that warrants ongoing monitoring. The most recent eruption in 1938 CE places this volcano within the modern era of volcanological observation.

Significance

With 12 recorded eruptions, Nemo Peak has a substantial eruptive history that provides valuable data for understanding volcanic behavior and assessing future hazards in the Northwestern Pacific Volcanic Regions region.

GVP Reference Summary

Nemo Peak volcano at the northern end of Onekotan Island in the northern Kuriles is truncated by two nested calderas of preglacial age, the largest of which is 10 km in diameter and extends to the northern coast. A third 5-km-wide caldera formed about 25,000 years ago by collapse of an interglacial cone that was constructed over the glaciated surfaces of the earlier calderas. The 1018-m-high central cone of Nemo Peak is composed of two coalescing andesitic cones that were constructed at the SW side of the youngest caldera and formed in four stages beginning in the early Holocene about 9500 years ago. Construction of the central cone has left the crescent-shaped Chernoe Lake at the NE end of the youngest caldera; lava flows from Nemo Peak form the broad SW shoreline of the lake. The final activity built a lava dome that completely overtops a 350-m-wide crater and has a 150-m-wide crater at its summit. Historical eruptions of Nemo Peak date back to the early-18th century.

— Smithsonian Institution, Global Volcanism Program