Moekeshiwan [Lvinaya Past]

Geography & Climate

Moekeshiwan [Lvinaya Past] is located in Japan - administered by Russia, within the Kuril Volcanic Arc of the broader Northwestern Pacific Volcanic Regions. Situated at 44.61° N, 146.99° E in the Northern Hemisphere, the volcano lies within a temperate climate zone. At just 495 meters above sea level, Moekeshiwan [Lvinaya Past] is a relatively low-elevation volcanic feature. Despite its modest height, it remains an active geological formation with the same underlying magmatic processes as its taller counterparts. The volcanic landform is characterized as a caldera, which describes the physical shape and structure of the volcanic edifice as observed from the surface.

Eruption History Summary

Moekeshiwan [Lvinaya Past] has 1 recorded eruption in the geological database, spanning from 10335 BCE to 10335 BCE. The most powerful recorded event was a colossal eruption capable of affecting global climate for years in 10335 BCE, reaching VEI 6 on the Volcanic Explosivity Index.

Significance

Moekeshiwan [Lvinaya Past] has produced at least one eruption of VEI 6 or higher, placing it among the most powerful volcanic systems on Earth. Eruptions of this magnitude inject massive quantities of sulfur dioxide into the stratosphere, affecting global climate by lowering average temperatures for one to three years after the event.

GVP Reference Summary

The rim of the 7 x 9 km Moekeshiwan [Lvinaya Past] caldera on southern Iturup Island drops to 50 m below sea level on the NW side. Lvinaya Past, meaning Lion's Jaw, derives from a rock formation resembling a sleeping lion. The caldera is breached on the NW, where a shallow 5-km-wide passage opens to the Sea of Okhotsk. The caldera floor is about 550 m below sea level and lies almost 1 km below the caldera rim. Radiocarbon dating places caldera formation in the late Pleistocene, around about 12,300 years ago (see Smirnov et al., 2025), which deposited thick dacitic pumice deposits that form the 50-60 m high Yuzhny (Southern) isthmus. No post-caldera features or activity have been reported. This volcano is not included in the list of active volcanoes by the Japan Meteorological Agency (2013).

— Smithsonian Institution, Global Volcanism Program