December 23, 2015. EN. Cerro Machin , Pacaya , Cotopaxi .
December 23, 2015.
Cerro Machin, Colombia :
Increase in activity: Extraordinary Bulletin of Cerro Machin volcano, December 22, 2015.
Subject: Internal Activities of Cerro Machin volcano. The level of activity: Yellow or (III) remains: changes in the behavior of volcanic activity.
Regarding the monitoring of the activity of the Cerro Machin volcano, the Colombian Geological Service reports that:
From today December 22, 2015 at 06h09 (local time), it was recorded an increase in volcano-tectonic seismic activity associated with the fracturing of the rock inside the volcano, that highlight two earthquakes at 6h09 (local time) and 6h22 (local time), with a magnitude of M3,0 on the Richter scale. These events were reported as felt by residents near the volcano and the municipality of Cajamarca, Tolima.
The location obtained by OVS–Manizales is:
Latitude: 29.39 4˚ ‘N
Longitude: 75˚ 23.31 ‘W
Depth: 3.96 km
Magnitude: 3.0 ML
Latitude: 29.39 4˚ ‘N
Longitude: 75˚ 23.48 ‘W
Depth: 4.09 km
Magnitude: 3.0 ML
It is recommended to the community to continue to keep abreast of changes in the current activity of the volcano.
The Colombian Geological Survey monitors the evolution of the volcanic phenomenon and will continue to report timely to the changes that may occur.
The small Cerro Machín stratovolcano lies at the southern end of the Ruiz-Tolima massif about 20 km WNW of the city of Ibagué. A 3-km-wide caldera is breached to the south and contains three forested dacitic lava domes. Voluminous pyroclastic flows traveled up to 40 km away during eruptions in the mid-to-late Holocene, perhaps associated with formation of the caldera. Late-Holocene eruptions produced dacitic block-and-ash flows that traveled through the breach in the caldera rim to the west and south. The latest known eruption of took place about 800 years ago.
Source : SGC , GVP.
Photos : Ingeominas.
Pacaya, Guatemala :
Reporting « in extenso » of T Pfeiffer, VolcanoDiscovery during the ascent to the Pacaya December 22, 2015 .:
During our visit at the volcano this morning, the first direct observation of the crater was possible following a period of 5 days of bad weather. When we climbed the crater rim, we observed violent, continuous lava spattering from the central vent on an intra-crater cinder cone inside Mackenney crater.
Activity was fairly regular in intensity, but went through alternating periods of stronger and weaker overall strength, lasting 10-20 minutes each. During the strongest phases, some stronger spattering events, resembling strombolian explosions (except that this activity was continuous), lava bombs were ejected to heights of 150-200 m, i.e. well above the crater rim, but mostly fell back inside. Only few fresh (days to few weeks old) bombs were seen on or near the (eastern) crater rim.
Around the main vent at the bottom of the the approx. 100 m deep crater, a small intra-crater cinder cone, about 15 m tall, has formed, obviously containing a small boiling lava lake in its main vent. A small secondary vent is located at the eastern side of the cone and also showed spattering occasionally, mainly during phases of elevated activity at the main vent. Parts of the crater floor have been covered by presumably fresh lava flows.
Source : T Pfeiffer / Volcanodiscovery
Photos : T Pfeiffer / Volcanodiscovery
Cotopaxi, Ecuador :
The volcano continues its moderate activity.
During the morning hours, it was observed gases and steam with low ash content, reaching a maximum height of 2500 meters above the crater level. At the moment, the volcano is covered by clouds.
Techniques and observations annex :
Since 06h00 (TL) until 17 h00 (TL), 34 events volcano tectonic (VT), 2 events of long period (LP), 2 emission tremor events were recorded.
Observations of emissions and ash:
During the morning, the area was discovered and the volcano was observed with continuous vapor emissions with low ash content that reached a height of 2500m above the crater, moving toward the West- Northwest .
In the evening, the volcano remains cloudy, making it impossible direct observation.
The issue value of Sulphur Dioxide is 634Tonnes / day with 71 valid measures.
There was no rain in the area.
Source : IGEPN
Photo : José Luis Espinosa Naranjo .