Recent Research

The following links are some of the available published research within the last 15 years regarding Karymsky Volcano.  Each is incorporated in the information throughout the blog.

1) Eruption of Andesite triggered by Dyke Injection: Contrasting Cases at Karymsky Volcano, Kamchatka and Mt. Katmai, Alaska  - Eichelberger and Izbekov, (2000).

The 1912 Mt. Katmai, Alaska and 1996 Karymsky volcano, Kamchatka eruptions were both triggered by the injection of dikes, which rose from depth.  The composition of the intrusion and its effect on the magma system dictates the eruption style.  A voluminous, silicic dike intersected the magma system in the Katmai/Novarupta region and caused a catastrophic, plinian-scale eruption.  The tephra showed discontinous zoning and the eruption resulted in the collapse of Mt. Katmai, forming the caldera which now sits atop the mountain.  In contrast, a voluminous, basaltic dike intersected the Karymsky region and magma chamber beneath Karymsky volcano.  The eruption was significantly smaller in magnitude and the tephra deposits show little to no zoning and the eruption continues today.  By contrasting two eruptions with similar circumstances, Eichelberger and Izbekov (2000) were able to deduce that the injection of silicic dikes have catastrophic effects, while the injection of mafic intrusions are less than catastrophic.
2) The 1996 Eruption of Karymsky Volcano, Kamchatka: Historical Record of Basaltic Replenishment of an Andesite Reservoir - Izbekov et al. (2004)

The simultaneous 1996 eruption of Karymsky volcano and Academy Nauk vent 6 km away provided a great example of mafic recharge into a andesite reservoir.  However, Academy Nauk erupted basalt for 18 hours, while Karymsky simultaneously erupted andesite and erupted continuously for the following 3 years.  The basalt erupted from Academy Nauk represents the parental mafic recharge.  A detailed petrographic study of the volcanic products of the Karymsky andesite showed evidence of basaltic replenishment and recorded the compositionally zoned andesitic magma chamber prior to the intrusion and eruption.  The plagioclase crystals within the Karymsky andesite had calcium-rich cores and were almost identical to the plagioclase crystals from the Academy Nauk basalts.  Additionally, olivine crystals occur as resorbed cores in pyroxenes, much like olivines found in the basalt from Academy Nauk.

Izbekov et al., (2004) used petrographic evidence to determine the sequence of events which led to the 1996 eruption of Karymsky.  The initial eruption was due to the mafic injection and pressure overload in the andesite magma chamber.  The top of the chamber erupted andesite explosively.  Following the initial eruption, basalt and andesite began mixing.  Eventually, the magma chamber established thermal and chemical equilibrium, with crystallization of the mixed liquid and zoning in plagioclase and olivine.    Izbekov et al., (2004) suggested that magm mixing and equilibrium was establshed fairly quickly due to the contrast in temperature, viscosity, and density between the two magmas.  

3) How a tectonic earthquake may wake up volcanoes: Stress transfer during the 1996 earthquake–eruption sequence at the Karymsky Volcanic Group, Kamchatka - Walter (2007)

Volcano-seismic data is perhaps the most useful data associated with predicting eruptions and evaluating its behavior.  Historically tectonic earthquakes have not have a profound effect on volcanic activity.  However, Walter (2007) provides evidence that in some cases, particularly the 1996 Karymsky eruption, tectonic earthquakes allowed the upward propagation of deep magma reservoirs, which led to the eruption of Karymsky and Academy Nauk.

Two days prior to the 1996 eruption, a 7.1 tectonic earthquake occurred 10-20 km south of Karysmky volcano and Academy Nauk caldera.  The earthquake occurred along a NE-SW fracture system, which also runs between the two 1996 vents, Karysmky and Academy Nauk.  Walter (2007) suggests that stress changes in the area may be of great importance in awakening a magma system and hazard associations should consider implementing a seismo-tectonic framework.  This research should be of significant interest to volcanologists and hazard specialists worldwide.

4) Thermal Monitoring of North Pacific volcanoes from space - Dehn et al. (2000)

Satellite imagery and thermal monitoring efforts in North Pacific helps predict and prepare for dangerous and remote volcanic eruptions in Alaska, the Aleutian Isalands, and the Kamchatkan Peninsula.  Thermal infrared data is collected multiple times per day by the Alaska Volcano Observatory (AVO) for this entire region.  After establishing a 6-year record and establishing background levels for each volcano, the tool has become very effective in predicting eruptions and mitigating air traffic hazards associated with eruptions in this region.

Karymsky volcano has erupted Strombolian/Vulcanian-style eruptions frequently since the onset of the 1996 eruption.  The activity is sporadic, each explosion only lasting seconds.  Hot, incandescent material is commonly scattered near the vent and small ash plumes are generated.  Despite, the large amount of activity at Karymsky, only faint thermal anomalies can be seen in cloud-free images.  Thermal signals depend largely on weather conditions and the timing of the eruption in relation to the timing of the satellite image.  The onset of larger and/or anomalous events can be clearly seen in the thermal data.  In November 1997, activity at Karymsky increased as seen by increased saturation-level temperatures.  The increased activity culminated in lava fountaining within the crater and the formation of a cinder cone.

The use of thermal monitoring is essential and very useful for volcanic hazard mitigation in the North Pacific and remote volcanoes, like Karymsky.

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