OVSICORI-UNA received reports at 05:30 on 26 February of pulsing white plumes rising from Rincon de la Vieja's active crater about every four minutes. ...more
The seismic records showed no signals associated with a phreatic eruption or sudden gas output. Cloud cover prevented views of the active crater during an overflight later that day, however clear views of the N and S flanks and areas SW showed no changes. [less]
The acid crater lake. On the right there are thermal convective cells (upwelling), mainly in the south and east of the lake (RSN)
Active crater with strong degassing (RSN)
The volcano has a very active hot lake whose degassing activity and temperature (48° C) increased after the magnitude 7.6 earthquake on 5 Sep. It has milky gray color due to mixing of sediments. ...more
On September 20 RSN staff made a visit to the active crater of Rincon de la Vieja Volcano, during which they collected a sample of lake water for subsequent chemical analysis and captured thermal images and videos, both of the surface of the lake and fumaroles, and compared them with images taken in April of 2012. This revealed that there has been an increase in the temperature of the lake, while the fumarolic field remained the same. [less]
Over the past weeks, the National Park of Rincón de la Vieja has been observing an increase in volcanic activity, and a small phreatic eruption occurred from the main crater on 11 April.
Seismic recording of a phreatic explosion at 00:16 local time on 19 February 2012
New phreatic explosions were recorded at Rincón de la Vieja volcano in northern Costa Rica. ...more
On 23 February, residents in Guachipelin (11 km to the SW) woke up to hear explosion sounds between 0400 and 0430 local time. Seismic recordings showed signals typical for explosions at the same time, although other residents in other areas did not hear any eruption. Similar seismic signals were detected on 19 Feb at 00:16 and on 20 Feb at 00:46 local time, suggesting that smaller explosions occurred then as well. [less]