Maly Semyachik
Caldera in Russia
Key Facts
Elevation
1,527 m (5,010 ft)
Type
Caldera
Location
54.135°, 159.674°
Region
Eastern Kamchatka Volcanic Arc
Rock Type
Basalt / Picro-Basalt
Tectonic Setting
Subduction zone
Location
Loading map...
Overview
Maly Semyachik is a compound stratovolcano located in a 10-km-wide caldera within the 15 x 20 km mid-Pleistocene Stena-Soboliny caldera. Following construction during the late Pleistocene of the Paleo-Semiachik volcano beginning about 20,000 years before present (BP), activity migrated to the SW, forming Meso-Semiachik (about 11,000-9,000 BP) and Ceno-Semiachik (about 8,000 BP to the present). An initial stage lasting about 3,500 years was dominantly explosive, constructing the present cone.
A second stage beginning about 4,400 years ago was marked by alternating constructive and destructive processes. A crater lake fills the historically active Troitsky Crater, which formed during a large explosive eruption about 400 years ago.
Volcanic Hazards & Risk Assessment
Primary Hazards
- Pyroclastic flows and surges
- Large explosive eruptions (VEI 4+)
- Ash fall and tephra deposits
- Lahars and debris flows
Risk Level
Geological Composition & Structure
Rock Types
Tectonic Setting
Age & Formation
Eruption Statistics & Analysis
| Metric | Value | Global Ranking | Significance |
|---|---|---|---|
| Total Recorded Eruptions | Unknown | Low | Moderately active volcano |
| Maximum VEI | VEI Unknown | Minor | Local impact potential |
| Recent Activity | 74 years ago | Historical | Recently active |
Monitoring & Alert Status
Monitoring Networks
Current Status
Nearby Volcanoes in Northwestern Pacific Volcanic Regions
Quick Info
- •Smithsonian ID: 300140
- •Evidence: Eruption Observed
- •Epoch: Holocene
About the Photo
Maly Semiachik is located within several nested Pleistocene calderas and composed of three overlapping edifices along a NE-SW line. Activity migrated to the SW, eventually forming the youngest cone, Ceno-Semiachik. It contains the historically active Troitsky crater, which formed during an explosive eruption about 400 years ago. It contains a hot, acidic lake this 1972 photo.
Photo by Oleg Volynets, 1972 (Institute of Volcanology, Petropavlovsk).
Authority Sources
Related Volcanoes
Basic Information
This page shows basic data from the Smithsonian Global Volcanism Program. For more detailed information, visit the official Smithsonian page.