Global Volcanism Program

10 March-16 March 2010

According to the Washington VAAC, INETER reported an eruption from Concepción on 12 March. A rapidly-dissipating ash cloud was seen on satellite imagery almost 60 km E of the summit.

Sources: Washington Volcanic Ash Advisory Center (VAAC)

Available Weekly Reports

10 March 2010 Back to Top

According to the Washington VAAC, INETER reported an eruption from Concepción on 12 March. A rapidly-dissipating ash cloud was seen on satellite imagery almost 60 km E of the summit.

Sources: Washington Volcanic Ash Advisory Center (VAAC)

3 March 2010 Back to Top

Based on information from INETER and analyses of satellite imagery, the Washington VAAC reported that on 8 March an ash plume from Concepción rose to an estimated altitude of 2.1 km (7,000 ft) a.s.l. The plume was last seen in satellite imagery later that day 227 km W.

Sources: Washington Volcanic Ash Advisory Center (VAAC)

9 December 2009 Back to Top

According to a news article, INETER reported that an explosion of ash and gas from Concepción on 11 December produced a plume that rose 150 m above the crater. Ashfall was reported in three nearby communities.

Sources: Reuters

19 December 2007 Back to Top

According to a news article, INETER reported that an explosion from Concepción on 20 December was followed by gas-and-ash plumes. Ashfall was reported in nearby communities.

Sources: Associated Press

4 July 2007 Back to Top

INETER reported that explosions in the crater of Concepción on 10 July produced ash-and-gas plumes that drifted NW. Ashfall was reported from areas downwind.

Sources: Instituto Nicaragüense de Estudios Territoriales (INETER)

18 April 2007 Back to Top

INETER reported that explosions in the crater of Concepción on 22 April produced ash-and-gas plumes that drifted WSW.

Sources: Instituto Nicaragüense de Estudios Territoriales (INETER)

11 April 2007 Back to Top

INETER reported that explosions in the crater of Concepción on 8 April produced an ash-and-gas plume that rose to an altitude of 2.7 km (8,900 ft) a.s.l. and drifted W.

Sources: Instituto Nicaragüense de Estudios Territoriales (INETER)

7 February 2007 Back to Top

INETER reported that explosions in the crater of Concepción produced ash-and-gas plumes that traveled down the WSW flanks on 9 February. Explosions continued on 10 February and produced minor ash-and-gas plumes. No seismicity was registered.

Sources: Instituto Nicaragüense de Estudios Territoriales (INETER)

3 August 2005 Back to Top

According to INETER by 0400 on 3 August, 38 earthquakes had occurred on the Island of Ometepe. The strongest earthquake (ML 5.6) occurred at 0603 and was felt in the surrounding region. The epicenter was estimated to be underneath Lake Nicaragua, SE of the Island of Ometepe, ~10-15 km SE of Volcán Maderas. This earthquake did not cause significant damage because the epicenter was not close to populated areas. The magnitude of this event was comparable to the 1972 earthquake in Managua.

Sources: Instituto Nicaragüense de Estudios Territoriales (INETER)

27 July 2005 Back to Top

According to INETER, an eruption occurred at Concepción on the island of Ometepe on 28 July at dawn. Ash fell in the town of Moyagalpa (W of Ometepe island), and in the zones of Rivas, San Jorge, Buenos Aires, Potosí, and Belén. Seismic tremor was recorded at a seismic station N of the volcano, but no large earthquakes were recorded. By the afternoon, ashfall had reduced considerably or completely ceased, while gas emission continued. No thermal anomalies were observed on satellite imagery. On 29 July during 0500-0800, a series of volcanic earthquakes occurred that may have been associated with small explosions in the crater. At 1025 the seismic station recorded a moderate explosion in the crater. On 31 July, seismic tremor occurred with slight variations. According to news articles, no one was injured by the eruptions.

Sources: Instituto Nicaragüense de Estudios Territoriales (INETER) , Associated Press

20 August 2003 Back to Top

According to news articles, INETER reported increased seismicity at Concepción on 21 August. People on the island of Ometepe did not feel the tremor, which ended on 22 August.

Sources: La Prensa (Nicaragua) , El Nuevo Diario

Summary of eruption dates and Volcanic Explosivity Indices (VEI).

Start Date	Stop Date	Eruption Certainty	VEI	Evidence	Activity Area or Unit
2009 Dec 11	2011 Mar 12	Confirmed	1	Historical
2008 Jul 30	2008 Jul 30	Confirmed	1	Historical
2007 Nov 24	2007 Dec 20	Confirmed	2	Historical
2007 Feb 9	2007 Jul 10	Confirmed	1	Historical
2006 Sep 1	2006 Sep 21	Confirmed	1	Historical
2005 Jul 28	2005 Nov 10	Confirmed	2	Historical
1999 Dec 27	1999 Dec 29 (?)	Confirmed	1	Historical
1988 Jun	Unknown	Confirmed	2	Historical
1985 Dec 2 ± 1 days	1986 Apr 20 (?)	Confirmed	1	Historical
1984 Dec	1985 Jan 2	Confirmed	1	Historical
1983 Mar 16	1983 Mar 25	Confirmed	2	Historical
1982 Jan 15 ± 5 days	1982 Feb 14 ± 5 days	Confirmed	2	Historical
1978 Mar 30 (in or before)	1978 May (in or after)	Confirmed	2	Historical
1977 Apr 4	1977 May 3	Confirmed	2	Historical
1973 Dec 24	1974 Jan 12	Confirmed	2	Historical
1963 May 9	Unknown	Confirmed	1	Historical
1962 Jun	1962 Jun	Confirmed	2	Historical
[ 1961 Nov 28 ]	[ 1961 Dec ]	Uncertain	2
1957 Mar 27	1957 Jul	Confirmed	2	Historical
1951 Jul	1955 May	Confirmed	2	Historical
1948	1950	Confirmed	1	Historical
1944 Apr	1945 Dec	Confirmed	2	Historical
1935 Feb	1935 Feb	Confirmed	2	Historical
1929 Aug	1929 Oct	Confirmed	2	Historical
1928 Jan 25	Unknown	Confirmed	2	Historical
1921 Dec	1926 May	Confirmed	2	Historical
1918 Jan	1919 Jul	Confirmed	2	Historical
1907 Sep	1910	Confirmed	2	Historical
1902	Unknown	Confirmed	2	Historical
1891 Apr	1891 Apr	Confirmed	2	Historical
1884	1886	Confirmed	2	Historical
1883 Apr 5 ± 4 days	1883 Jun 30	Confirmed	2	Historical
[ 1800 ± 50 years ]	[ Unknown ]	Uncertain	2
770 BCE ± 50 years	Unknown	Confirmed	4	Radiocarbon (uncorrected)	East flank (Las Pilas, Sintiope)

Volcán Concepción is one of Nicaragua's highest and most active volcanoes. The symmetrical basaltic-to-dacitic stratovolcano forms the NW half of the dumbbell-shaped island of Ometepe in Lake Nicaragua and is connected to neighboring Madera volcano by a narrow isthmus. A steep-walled summit crater is 250 m deep and has a higher western rim. N-S-trending fractures on the flanks of the volcano have produced chains of spatter cones, cinder cones, lava domes, and maars located on the NW, NE, SE, and southern sides extending in some cases down to Lake Nicaragua. Concepción was constructed above a basement of lake sediments, and the modern cone grew above a largely buried caldera, a small remnant of which forms a break in slope about halfway up the north flank. Frequent explosive eruptions during the past half century have increased the height of the summit significantly above that shown on current topographic maps and have kept the upper part of the volcano unvegetated.