A new eruption of Costa Rica's Turrialba volcano took place at 03:37 UTC on June 25 (22:15 on June 24, local time). Dense fog is preventing estimation of volcanic cloud height. At the same time, volcanic ash produced by the fresh eruption of Guatemala's Fuego volcano is reaching 4.9 km (16 000 feet) above sea level.
Tremors under Turrialba started increasing at 02:05 UTC and reached maximum at 02:40 UTC. This seismicity was accompanied by the occasional passive emission of ash. At the time, the direction of the wind was WNW.
A strong smell of sulfur was reported in Escazú (San Jose) and San Isidro De Heredia (Heredia), OVISICORI reported.
At 03:37 UTC (21:37 local time), the tremors further increased, RSN said. They were accompanied by the constant emission of ash. This time, winds direction was SW, Dr. Mauricio M. Mora said.
At the time of the RSN's last report (05:00 UTC), ash was still coming out of the volcano.
This thermal image was recorded between 03:35 UTC and 03:51 UTC on June 25:
Meanwhile, Guatemala's Fuego volcano is also erupting. At 04:45 UTC on June 25, volcanic ash cloud was near 4.9 km (16 000 feet) above sea level, the Washington VAAC reported. INSIVUMEH reported movement toward the WSW-SW, extending roughly 18.5 km (11.5 miles) from the summit.
Volcanic ash is seen in multi-spectral imagery, but it is difficult to see its complete view.
In a special bulletin issued at 04:40 UTC (22:40 local time), INSIVUMEH said the activity at the volcano is increasing. "Over the last 22 hours, Fuego volcano observatory reported increased number of explosions, constant rumblings, and strong shock waves. The seismic station FG3 recorded increased tremor and constant explosions."
Two lava flows were observed on the southeast flank flowing into Las Lajas and El Jute drainages. They were about 2 km (1.2 miles) in length.
"At the time, this eruption is effusive in nature, however, there is a chance it could increase in the coming hours, with the possibility of pyroclastic flows, mainly on the southeast and southern flank," INSIVUMEH said.
Turrialba, the easternmost of Costa Rica's Holocene volcanoes, is a large vegetated basaltic-to-dacitic stratovolcano located across a broad saddle NE of Irazú volcano overlooking the city of Cartago. The massive 3340-m-high Turrialba is exceeded in height only by Irazú, covers an area of 500 sq km, and is one of Costa Rica's most voluminous volcanoes.
Three well-defined craters occur at the upper SW end of a broad 800 x 2200 m summit depression that is breached to the NE. Most activity originated from the summit vent complex, but two pyroclastic cones are located on the SW flank. Five major explosive eruptions have occurred during the past 3500 years. A series of explosive eruptions during the 19th century were sometimes accompanied by pyroclastic flows. Fumarolic activity continues at the central and SW summit craters. (GVP)
Volcán Fuego, one of Central America's most active volcanoes, is one of three large stratovolcanoes overlooking Guatemala's former capital, Antigua. The scarp of an older edifice, Meseta, lies between 3 763 m (12 345.8 feet high Fuego and its twin volcano to the north, Acatenango. Construction of Meseta dates back to about 230 000 years and continued until the late Pleistocene or early Holocene. The collapse of Meseta may have produced the massive Escuintla debris-avalanche deposit, which extends about 50 km (31 miles) onto the Pacific coastal plain.
The growth of the modern Fuego volcano followed, continuing the southward migration of volcanism that began at Acatenango. In contrast to the mostly andesitic Acatenango, eruptions at Fuego have become more mafic with time, and most historical activity has produced basaltic rocks. Frequent vigorous historical eruptions have been recorded since the onset of the Spanish era in 1524 ,and have produced major ashfalls, along with occasional pyroclastic flows and lava flows. (GVP)
Featured image credit: RSN