During the last year we have been spoilt by eruptions on the Kamchatkan peninsula. We had a medium sized effusive eruption from Tolbachik, a long explosive eruption with lava effusion at Klyuchevskoy, explosive eruptions at Bezymianny, anyone I missed? UKViggen emediately pointed out that I had missed to mention Sheveluch, Kizimen and Karymsky (I still have the nagging feeling there is one more out there).
Now we have a new and more unexpected volcano entering into the party, namely the Zhupanovsky. Zhupanovsky is the latest of four stratovolcanoes to evolve from a Pleistocene 36 by 22 kilometer caldera. The previous 3 stratovolcanoes have not erupted during the Holocene, of the 3 older volcanoes Dzenzursky is the largest. It is in its own way impressive with a horse-shoe shaped flank caldera, evidence of major flank collapse/eruption.
It is believed that Zhupanovsky is a fairly young volcano that came to life 7 000BC, and that the first 2 to 3 000 years was predominantly filled with frequent mild and effusive eruption that rapidly built up the volcanic edifice. After that a period of larger eruptions followed that seems to be infrequent, but historical records tell us that the volcano tends to have frequent small eruptions with big ones interspersed at long intervals.
The last big eruption was somewhere between 1 000 to 800BC (VEI-6?). Since 1776 up to 1959 it suffered from a minimum of 7 confirmed VEI-2 eruptions, but there is a possibility that there have been more that has not been observed due to the remoteness of the area. The top of the volcano has remained hydrothermally active after the last eruption.
KVERT has issued a report today of an ongoing eruption at Zhupanovsky with a 3 kilometer high ash column. The eruption is currently color coded ORANGE. It is still uncertain if the eruption is magmatic or if the volcano is still in a throat clearing stage with predominantly phreatic components.
So far there is nothing pointing towards this becoming a large eruption, but it is not totally impossible that the eruption will grow further, especially if this turns out to be just the throat clearing phase. After all, this would be a VEI-2 throat-clearing.
More information and hopefully camera links will be added as we find them.