Report on Ekarma (Russia) — November 2010
Bulletin of the Global Volcanism Network, vol. 35, no. 11 (November 2010)
Managing Editor: Richard Wunderman.
Ekarma (Russia) Kuril Island stratovolcano erupts starting June 2010
Please cite this report as:
Global Volcanism Program, 2010. Report on Ekarma (Russia). In: Wunderman, R (ed.), Bulletin of the Global Volcanism Network, 35:11. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN201011-290270.
48.958°N, 153.93°E; summit elev. 1170 m
All times are local (unless otherwise noted)
Ekarma, located in the Northern Kurile Islands, generated a modest flank eruption on 30 June 2010 after weeks of emitting steam plumes from the summit and from areas on the same SW flank where the eruption ultimately vented ash. Beginning on 16 June, witnesses 42 km away heard anomalous booming noises.
A few of the available photos documenting the escalating plumes are included in this report. The tallest plume seen reached ~3 km altitude. Steaming or weakened eruption continued in August when volcanologists first set foot on the island. They found Ekarma had erupted from a fissure on the upper SW slopes (at 500- to 600-m elevation). Fine ash reached up to 5-6 cm deep in some places. Fresh ash-bearing lahars had developed along SW-flank drainages. The volcano was still steaming in late September 2010.
Regional maps and supplementary information appear in a subsection below. Figure 1 contains a photo of Ekarma taken in 2008.
Information summarized here and below came from a recent report (Levin and others, 2010) submitted to GVP by Alexandr V. Rybin. Rybin is the director of the Sakhalin Volcanic Eruption Response Team (SVERT) and served as group leader on the international volcanology expedition mounted in August 2010.
Levin and others (2010) described Ekarma's state during two time intervals and by two separate groups in mid-2010. One group, biologists, working on a neighboring island during 28 May-11 July 2010 first noticed a multi-week escalation of steaming at multiple vents, heard noises, and then saw the initial ash-bearing eruption on 30 June 2010.
Another group, volcanologists, both saw the eruption from distance and landed on the still-active volcano in early August. This team sailed into the region on the oceanographic vessel Nadezhda (figure 1). Report authors were listed as follows: Levin, B.V., Rybin, A.V., Chibisova, M.V., Degterev, A.V., Neroda, A.S., Melekestsev, I.V., and Izbekov, P.E. (see affiliations below under Information Contacts).
In terms of geology, Ekarma is a single stratovolcano formed by numerous lava flows. Many of the flows exposed at the surface reach up to ~3 km length and reached the coast to form resistant lobate promontories. Until this recent eruption, all the known eruptions vented from the summit crater. The last of the lava flows was viscous, of fan-like form, and it descended to the W.
After the lava flows, a lava plug extruded at the summit forming the spiny relief there that remains today. Gorshkov (1967) found this extrusion occurred during 1767-1769, this comprising the volcano's oldest known historical eruptive date. In the first half of 19th century, fumarolic activity was observed at the volcano. At the beginning and middle of the 20th century, the pattern of fumarolic activity varied (Gorshkov, 1967).
One other pre-2010 eruption is known. On 24 May 1980 observers on a passing ship noted a series of explosions lasting an hour. The resulting black eruptive column reached an altitude of over 1 km (Ivanov and others, 1981).
A plume was not apparent on photos from 1992. After receipt of this report, Bulletin editors found photos of Ekarma on Google Earth and the photo-sharing website Panoramio. They were taken in 1992 by Edward Ivey from distance. Correspondence with Ivey confirmed that he did not recall seeing any memorable signs of unrest at Ekarma.
The report authors looked at satellite images collected during the years 2000-2008 from sources offering free image-access on the internet. In those images, the authors found that fumarolic steaming from the summit varied. Quiet prevailed in 2007 or 2008 when scientists on passing a research ship scientists saw the volcano and documented an absence of fumarolic activity (Levin and others, 2009).
June 2010 observations made 42 km away. The information in Levin and others (2010) about Ekarma's observed eruptive behavior during June came from Andrey S. Neroda (Pacific Oceanographic Institute FEB RAS), who along with fellow researchers watched the volcano during 28 May-11 July 2010. They were in the region conducting population studies on sea lions on Skala Dolgaya Island (in the Lovushki Islands). That vantage point (the location of their photos) lies ~42 km SW of Ekarma Island.
The biologists first noticed higher steam-gas emissions at the volcano at the beginning of June. On 13 June there emerged three isolated points of strong steam emission (vigorous fumaroles) on the S slope and summit.
In the latter half of 16 June the group on Skala Dlinnaya Island heard booming noises. The sounds occurred 8-10 times in a time interval lasting 30-40 minutes. In the next days the team heard other, softer noises.
The 18 June steam plumes were similar to those on the 13th. A prominent white cloud judged as a plume stood over the summit on the 29th. Three distinct steam plumes emerged on 30 June (figure 2), and the same day the ash-bearing phase occurred.
In the evening of 30 June observers began to see volcanic explosions with emission of ash up to 3 km altitude. No ash fall was detected on Skala Dolgaya Island. In addition to the photos, the same witnesses took some low-resolution video on 30 June. Three lahars went down from the vent area of the middle venting site, one trending S, the other two roughly SW.
The August expedition put to sea on the 109-m-long, 3-masted, square-rigged ship Nadezhda. The Nadezhda serves the Nevelskoy Maritime State University (Vladivostok, Russian Far Eastern Federal District) and to sail her requires a crew of 50 persons.
Levin and others (2010) reported that eruptions continued as the Nadezhda approached Ekarma. The team had initially set out with the primary intent of visiting Sarychev Peak and the adjacent volcano and island, Raikoke, but during the expedition they learned of increasing activity at Ekarma and revised plans in order to visit there as well.
On 10 August 2010 observers saw an Ekarma plume from their anchorage between Raikoke and Matua Islands ~90 km SW of Ekarma. The plume was sustained all day on the 10th, described as a steam-gas column light gray in color and reaching ~2 km altitude. In similar manner to the June observations, the vent discharging the emissions was not at the 1,170-m summit but on the SW flank at elevation of 500-600 m.
During 11-23 August, the expedition worked at Matua Island (Dvoinaya Bay, studying Sarychev Peak), watching Ekarma from 105 km SW. During this period visibility was sufficient on the days 14 and 22 August to enable observers to see smaller steam-gas columns that rose to 1.6 km altitude. Nadezhda left Matua Island on 24 August. On Ekarma, the team found the volcano and surroundings tephra covered. With distance from the active vent, the fine gray airfall ash decreased in thickness and became finer grained.
At the elevation of ~300 m the team found the ash 1-2 mm thick; in the near-summit part of the volcano at ~900 m elevation, they found it 4-6 cm thick and bearing some coarser-grained components. Small lahars had descended along the volcano's southern slope down to the sea (figure 3).
The eruption influenced the island's flora. At 250-300 m elevation the plants began to display signs of stress. At ~550 m and higher elevation most of the smaller plants had dried up, and larger bushes (willow, alder) showed distinct signs of influence such as dried leaves due to contact with ash and related impacts of the eruption.
Authors suggested that the main factor influencing plant damage was not the high temperature of tephra, because tephra of such fine-grain size falls from the air with little residual heat. Instead, chemical burns from volcanic gases and water-soluble condensate were interpreted to have caused the damage. Many of the damaged plants were expected to rebound in the next growing season. Along drainages where lahars descended, the soil-vegetative layer was sometimes destroyed.
After the expedition, steam-and-gas emissions continued into at least late September. For example, an image of the island from the QuickBird satellite taken 20 September 2010 shows a wisp of white plume over the upper slopes (figure 4).
On figure 8 steam-gas emissions appeared limited to the 2010 vent and upper areas of the volcano. Earlier observations had documented S flank lahars. Based in part on water discoloration assumed to come from suspended particles transported by near-shore currents, lahars by this time had also descended along the N flanks (and possibly down other island drainages as well). An International Space Station photo of the volcano is also available from the same day showing a similar plume, but much of the surrounding scene is masked by clouds.
Levin and others (2010) made a preliminary volume estimate for the erupted material, 2 x 105 m3. They noted that this would place the eruption's volcano explosivity index (VEI) at 1 (Siebert et al, 2010).
Figure 5 shows Ekarma's location, and although this region is both remote and sparsely inhabited, this volcanic chain lies beneath, alongside, and frequently upwind of major North Pacific aviation routes, corridors that in 1998 served more than 20,000 passengers and millions of pounds of cargo on a daily basis (Miller and Casadevall, 2000). For a recently issued compilation of known aircraft-ash incidents, see Guffanti and others (2010).
To help illustrate regional geography, Ekarma lies 880 km E of Vladivostok (V on the inset map at lower right). On the map at upper left, labeled cities are Y, Yuzhno-Sakhalinsk, S, Sapporo, P, Petropavlovsk-Kamchatsky, and T, Tokyo (~1,500 km SW of Ekarma).
Ekarma's June 2010 eruption began months after that of Iceland's Eyjafjallajökull (BGVN 35:03 and 35:04), and ash plumes from that eruption severely restricted European air traffic for a week. That disruptive event enlightened many in the public about the hazards of ash and aviation. In contrast to that eruption, the one at Ekarma failed to generate large, tall eruption plumes, and thus produced relatively little if any aviation impact. Ekarma's reported plume heights only reached as high as 3 km altitude, whereas most commercial aircraft cruse at altitudes ~4-fold higher. Still, volcanoes of the Kurile Islands occur close to the flight lines radiating from Asian population centers (figure 5, upper left). They also present aviation challenges in that they collectively lack in situ monitoring instrumentation, and they are generally devoid of residents to observe and alert authorities of eruptions.
Our recent Bulletin issues and Weekly Volcanic Activity Reports (WVAR) have discussed other Kurile Island eruptions, some of which we briefly mention here as background on this important region. Sarychev Peak (at the NW end of Matua Island) suddenly erupted during June 2009 severely disrupting aircraft routing; and weaker phases of the eruption possibly continued later (BGVN 34:06 and 35:09). Tiatia volcano was the scene of occasional thermal anomalies in satellite images during February-June 2010 (BGVN 35:07).
At the N end of the Kurile archipelago, two volcanoes on Paramushir Island have been active in the past few years. Ebeko is one of the Kurile's most active volcanoes, with repeated eruptions and emissions in recent years (BGVN 34:08, 30:06, 34:08, 30:06, 29:04, 18:08, 14:11, 14:05, 12:12, and 12:10, and with many WVAR in 2009 and some in 2010 due to a small ash-bearing eruption during that year). Chikurachki erupted sporadically during 2006-2008 (BGVN 31:03, 32:05, 33:03, and 33:08) and in multiple earlier cases as well.
References. Casadevall, T., and Thompson, T., 1995, World map of volcanoes and principal aeronautical features (1:34,268,000 at equator): U.S. Geological Survey, Geophysical Investigations Map GP 1011 (Mercator projection)
Gorshkov, G.S., 1967, Volcanism of the Kurile Island arc. Nauka, Moscow
Ivanov B.V., Chirkov A.M., Dubik Yu.M., Gavrilov V.A., Stepanov V.V., Rulenko O.P., and Firstov P.P., 1981, The State of the volcanoes of Kamchatka and the Kurile Islands in 1980. Volcanology and seismology, 1981. 3. P. 99-104.
Guffanti, M., Casadevall, T.J., and Budding, K., 2010, Encounters of aircraft with volcanic ash clouds; A compilation of known incidents, 1953–2009: U.S. Geological Survey Data Series 545, ver. 1.0, 12 p., plus four appendixes including the compilation database. URL: http://pubs.usgs.gov/ds/545
QuickBird, 2010 [satellite image distributed by Digital Globe, digitalglobe.com, http://browse.digitalglobe.com/]; Image's current URL: http://browse.digitalglobe.com/imagefinder/showBrowseMetadata?catalogId=101001000C504F00
Levin B.V., Fitzhugh B., Bourgeois D., and others, 2009, Complex expedition in the Kurile Island in 2008 (III stage), Vestnik of Far East Branch of Russian Academy of Sciences, 2, p. 134-142.
Siebert, L., Simkin T.S. and Kimberly, P., 2010, Volcanoes of the World: a regional directory, gazetteer, and chronology of volcanism during the last 10,000 years, 3rd edition, University of California Press, Berkeley, CA, 551 p.
Levin, BV, Rybin, AV, Chibisova, MV, Degterev, AV, Neroda AS, Melekestsev, IV, and Izbekov, PE, 2010, Activity increasing of Ekarma volcano in June 2010 (informal report submitted to BGVN).
Miller, T. P., and Casadevall, T. J., 2000, Volcanic ash hazards to aviation: in Sigurdsson, Haraldur, (ed.), Encyclopedia of Volcanoes, San Diego, Academic Press, p. 915-930.
Geologic Background. The small 5 x 7.5 km island of Ekarma lies 8.5 km N of Shiashkotan Island along an E-W-trending volcanic chain extending westward from the central part of the main Kuril Island arc. It is composed of two overlapping basaltic-andesite to andesitic volcanoes, the western of which has been historically active. Lava flows radiate 3 km in all directions from the summit of the younger cone to the sea, forming a lobate shoreline. A lava dome that was emplaced during the first historical eruption, in 1776-79, forms the peaked summit of the island.
Information Contacts: B.V. Levin, A.V. Rybin, M.V. Chibisova, A.V. Degterev, Sakhalin volcanic eruption response team (SVERT), Institute of Marine Geology and Geophysics FEB RAS (IMGG FEB RAS), 693022, Russia, Yuzhno-Sakhalinsk, Nauki str. 1B (URL: http://www.imgg.ru/); A.S. Neroda, Pacific Oceanological Institute FEB RAS (POI FEB RAS) 690041, Russia, Vladivostok, Baltiiskaya str. 43 (URL: http://www.poi.dvo.ru/rus/index.html); I.V. Melekestsev, Institute of volcanology and seismology FEB RAS (IVS FEB RAS) 683006, Russia, Petropavlovsk-Kamchatsky, Piipa av. 9. (URL: http://www.kscnet.ru/ivs/); P.E. Izbekov, Geophysical Institute, University of Alaska Fairbanks, 903 Koyukuk Drive, Fairbanks, AK 99775, USA.