January 29 , 2016. EN. Popocatepetl , Erebus , Momotombo .
January 29 , 2016.
Popocatepetl, Mexico :
January 28 11:00 h (January 28 17:00 GMT)
In the last 24 hours, the seismic records of the surveillance system at Popocatépetl volcano registered 5 low-intensity exhalations, and two explosions, the first one yesterday at 12:27 h and the second one tonight at 00:49 h; this last one expelled incandescent fragments up to 2 km from the crater.
Additionally, during this period several episodes of harmonic tremor were registered, which in total added up to 362 minutes. This activity is related to the process of construction of a lava dome presently inside the crater.
Yesterday, with the aid of the Federal Police, an over flight was made, during which it the presence of a 300 m in diameter dome was verified, which has filled the inner crater almost to the level of the main crater´s floor . The presence of this dome implies the possibility of further explosions in the next few days, of similar or even slightly larger magnitude than tonight´s, which destroy it.
Since this morning and up to the time of this report the volcano has been visible, with a slight emission of steam and gases which the winds disperse towards the east-northeast .
CENAPRED emphasizes that people SHOULD NOT go near the volcano, especially near the crater, due to the hazard caused by ballistic fragments .
This type of activity is included within the scenarios Volcanic Traffic Light Yellow Phase 2.
Source : Cenapred.
Photos : Cenapred , Luis Garcia.
Erebus, Antartique :
We continue to share information that the Team « Erebus » put on its Facebook page. (Mount Erebus Volcano Observatory).
The Erebus team on the ice goes by its National Science Foundation project number G081. The G081 team is undertaking a varied menu of research projects each with their own goals and objectives.
1) GPS measurements .
A New Mexico Tech team is making campaign (short term) GPS measurements of 8 permanent bench marks around Ross Island and on the summit area of Erebus volcano. This supplements 6 permanent continuously running GPS scattered around the volcano. The GPS date will examine deformation of the crater and look at how Ross Island is sinking under its own weight.
2) Volcanic gas emissions.
Annual measurements are made of the composition and quantities of volcanic gases emitted from the lava lakes in the summit crater using IR and UV spectrometers. The data are used to monitor the behavior of the underlying magmatic system and for annual comparisons to assess if any major changes are happening at depth in the volcano. This year one specialist in volcanic gas emissions is characterizing the nature of the aerosols (tiny gas and solid particles) which provide insight into how the dissolved volcanic gas becomes bubbles and drives the movement of the magma to the surface. The unique chemical signature of the aerosols can be used to identify the dispersion of the Erebus plume around Antarctica and its deposition in the snow.
3) Seismic Observations.
Seismic signals caused by eruptions and earth movements in the volcano are monitored year round to look for changes in the activity that may herald the onset of larger eruptions. The network of 4 older short-period and 5 newer broadband seismometers need annual maintenance and replacement of batteries and components that fail during the harsh Antarctic winters.
4) Magma Composition.
Periodically Erebus has small eruptions that can hurl large volcanic bombs out of the lava lake onto the crater rim where they can be sampled for analysis. The magma in the laka is a very special and unique composition called phonolite. Large anorthoclase feldspar crystals in the phonolite record how the magma in the deep storage chamber circulates. Although the lava lake has remained uniform in composition for over 30 years it is prudent to look for changes in the composition which could affect the eruptive activity.
5) Lava lake observations.
The lava lake(s) which are one of the unique characteristics of Erebus volcano are the top of the deeper magmatic system that metaphorically is the heart of the volcano. We image the main lake using a thermal IR camera to monitor circulation and thermal fluxes. A laser range finder called a LIDAR give us precise location information and monitors a persistent 10-16 minute pulsation of the lake surface. This year we are testing a new novel radar system especially designed and built for Erebus to make better observations of the main lava lake and its motions. ts.
Age dating of older lavas on a volcano gives insight into the eruptive history and can be used to predict future activity. We have used the build-up of an isotope of He produced by bombarding cosmic rays to date the youngest lavas. We are working cooperatively with colleagues from the Korean Polar Research Institute to use the same technique to examine the recent eruptive activity of Mt Melbourne another “active” volcano 200 miles north of Erebus. While in the area we are searching for volcanic ash erupted from Erebus and other local volcanoes. Dark layers of ash are common in “blue” ice areas and are a valuable record of the volcanic eruptions which can be used as time markers and provide a valuable history of potential environment impacting eruptions.
Source : Mount Erebus Volcano Observatory
Momotombo, Nicaragua :
Momotombo continues to present microseismic activity related to volcanic fluids circulating beneath the volcano. During the night glow was observed in the crater of the volcano, because the exhalations of gases at high temperatures.
The seismic amplitude in real time (RSAM) shows low to moderate values between 140 to 600 units. A high probability of occurrence of explosion of gases, ash and even expulsion of incandescent material remains.
Source : Ineter
Photo : OH