February 16 , 2017. EN. Turrialba , Piton de la Fournaise , Nevado Del Ruiz , Fuego .
February 16 , 2017.
Turrialba , Costa Rica :
Clarification of OVSICORI on State of activity of Turrialba volcano
OVSICORI-A · Wednesday 15 February 2017
Recently there have been statements in the press about the state of activity of the Turrialba volcano. In these statements it was stressed that the activity of this volcano poses no danger to the lives of workers on the Turrialba Volcano National Park and tourists who visit the top of the volcano. These assessments of the volcano’s activity do not take into account both the eruptive history of the volcano, its recent and current activity, and the infrastructure of the same national park. Recall that the volcano has exhibited explosive activity since 2010, with the launch of ballistics of decimetric sizes to more than 1 kilometer, pyroclastic flows that exceeded the kilometer and half and since September 2016 where it was recorded volcanic tremors more stronger than what is known since the volcano became active in 1990. At present the volcano has frequent strombolian eruptions, emitting fragments of hot rock more than 500 meters.
For several years, deformation of the soil around and under the volcano has been recorded indicating the intrusion of a large magmatic body, resulting in high seismic activity, strong gas and aerosol plumes, and repeated eruptions since October 2014. This indicates that the volcano is active and will continue in a state of eruption for a prolonged period until crystallizes the magmatic body. This body near the surface could come into contact with aquifers under the Turrialba, producing volcanic phreatomagmatic explosions with unpredictable consequences.
The simplified volcanic hazard map, prepared by C.N.E, tells the geological history of a Turrialba capable of producing large eruptions with the possibility of affecting several kilometers around the summit, with pyroclastic flows, lahars and ballistic emissions. If it happened in the past, this can be repeated in the present. On a volcano like Turrialba, which is clearly active, with an open system, there is no distinguishable precursor activity of high activity seismic, fumaroles or eruptive activity before a large eruption. It is irresponsible to attract tourists to a high-risk area where large-scale disasters can occur without notice or short notice.
On the other hand, Turrialba Volcano National Park does not have the minimum infrastructure to protect human lives from such an eventuality. Access roads have never been adequate. In the event of an eruption it would not be possible to evacuate visitors within a reasonable time. At the top, there is no infrastructure to guard against ballistics, collapses of ash columns and fiery clouds, such as bunkers that are on volcanoes in other parts of the world.
It is important to remember in this news what happened on the Ontake in Japan in September 2014, when 54 tourists were killed by the appearance of a phreatomagmatic eruption, which took place without notice. Today, the families of these 54 people are suing the Japanese state for the death of their relatives.
For all of the above, OVSICORI recommends respecting the decisions of the CNE, which limit access to the volcano established within the 2 km radius, with extensions to 5 km when the situation demands. The spectacle represented by an active volcano, the dimensions of it, can be seen in all their splendor around the volcano at a safe distance.
This document has been prepared by:
Dr Geoffroy Avard, Gel. Jorge Brenes, MSc. Monserrat Cascante, Dra. María Martínez, Dr. Maarten de Moor, le Dr Cyril Muller, M. Javier Pacheco, le Dr Marino Protti, Bach. Floribeth Vega, Lic. Carlos Montero.
Report of the activity of the Turrialba volcano of 14 February 2017 – 11:00
The Turrialba volcano maintains a continuous seismic tremor of variable amplitude, which is generally between medium and large amplitudes. During the day yesterday, it remained high value, to descend at midnight and increase again from 9 am to today and remain variable. Emissions were continuous, containing gases, aerosols and very low ash. The winds moved this material in several directions, mainly in the Northwest and South-West. So far, only a strong smell of sulfur in San Pablo de Oreamuno has been reported this morning.
Source : Ovsicori
Photos : Archives ( Ovsicori, Roxifotografia)
Piton de la Fournaise , La Réunion :
The eruption begun on January 31, 2017 at 7:40 pm local time continues. In the last 24 hours, the volcanic tremor (indicator of surface eruptive intensity) has decreased to a level equivalent to that of the beginning of the eruption (Figure 1).
Figure 1: Evolution of the RSAM (volcanic tremor and eruption intensity indicator) between January 31st and February 15th (16h local time) on the seismic station of Château Fort, located on the southern flank of the volcano. (© OVPF / IPGP)
– No seismicity was recorded during the day under the summit of Piton de la Fournaise.
– No significant deformation has been observed in the last few days.
– CO2 concentrations in the soil at the level of the volcano deposit are low.
Surface flows are estimated to be <1 and 2.4 m3 / s, based on satellite data from the HOTVOLC (OPGC – Clermont Ferrand) and MIROVA (Turin) platform.
The escaping layer of lava was measured at 14 m thickness and the regular flow of the lava is of the order of 10 m3 / s. Since the beginning of this eruption (January 31st), the volcanology observatory estimates the amount of lava sprayed by la Fournaise at a range of 5 to 8 million m3.
The front of the flow is now located at the top of the great slopes, about 6 km from the sea, but it is a priori unlikely that it descends lower.
Source : Ovpf
Nevado Del Ruiz , Colombia :
Weekly activity bulletin of the volcano Nevado del Ruiz, from 7 February to 13 February 2017
The level of activity continues: at the level activity yellow or (III): changes in the behavior of the volcanic activity.
Regarding the monitoring of the activity of the volcano Nevado del Ruiz, the Colombian Geological Survey reports that:
During the week, various monitoring parameters show that the volcano Nevado del Ruiz remains unstable. Seismic activity related to the fracturing of volcanic rock under the volcano showed a slight increase in the number of recorded earthquakes and a decrease in the seismic energy released compared to the previous week. This seismicity was located mainly in the South-East, South-West, North-East and, to a lesser extent, in the Arenas crater and in the North and North-West sectors. The depths of the earthquakes were between 1.0 and 6.8 km. The maximum magnitude recorded during the week was 0.8 ML (local magnitude), which corresponds to the earthquake recorded on 10 February at 00:08 (local time), 3.4 km 4 km southwest of the Arenas crater.
Seismicity related to fluid dynamics in the volcanic structure ducts was characterized by the appearance of earthquakes with varying levels of energy, long period (LP) and very long period (VLP), Tremor pulses and multiple fluid earthquakes. This type of seismicity has retained the same tendency both in number and in seismic energy released, as observed during the previous week. The earthquakes were mainly located in the Arenas crater and to a lesser extent in the southeast sector of the volcano. Some of these seismic signals have been associated with emissions of gases and ash into the atmosphere, as confirmed by the cameras installed in the volcano region and reports from the Los Nevados National Park (Pnnn). Several volcanic tremor pulses recorded on 13 February, resulted in volcanic ash emissions deposited in the northeast sector of the volcano in the towns of Murillo and Libano (Tolima) due to the direction and speed of the wind . The recording of seismic signals of this kind is not excluded with higher energy levels which may be associated with emissions of gas and ash. It is important to remember that ash emission processes can occur over several days and sometimes several times a day, without involving an individual report for each episode.
Volcanic deformation, measured from electronic inclinometers, Global Navigation Satellite Systems (GNSS) and satellite images to determine changes in tilt, position and shape of the volcano, continues to record in recent months a deflationary process and intermittent inflation / deflationary impulses, possibly linked to the emission of gas and ash.
The volcano continues to emit significant amounts of water vapor and gases, including sulfur dioxide (SO2), as evidenced by the values obtained by the SCANDOAS stations installed in the volcanic analysis area and on the satellite image. In the monitoring of the information provided by the Mirova site, 6 thermal anomalies were identified on 09, 10, 12 and 14 February with different energy values, the most important of which was recorded on 12 February with a value of 21 MW .
The column of gas, steam and ash from time to time reached a maximum height of 1500 m measured on the top of the volcano on February 09. The direction of dispersal of the column was in line with the dominant wind regime in the area, which predominated during the week to the southwest and sometimes south-east and north-east of the volcano.
The volcano Nevado del Ruiz continues to activity level Amarillo.
Source : SGC
Fuego , Guatemala :
Activity type: Vulcanian
Morphology: composite stratovolcan
Geographical location: 14 ° 28’54˝ Latitude N; 90 ° 52’54˝ longitude W.
Weather conditions: Clear
Wind: Northeast 5 km / h
Precipitation: 23.5 mm.
Maintains of low white degassing fumaroles at an altitude of about 4,200 meters (13,779 feet) scattered to the south, southwest and west. 27 explosions were reported, 16 low, 11 moderate, resulting in columns of gray ash at a height of about 4,500 to 4,800 meters (14,763 to 15,748 feet) extending 11 km to the south, southwest and west . Some explosions were accompanied by weak rumblings. An incandescence at a height of 150-200 meters above the crater generated weak to moderate avalanches on the outline of the crater towards the ravines of Santa Teresa, Ceniza and Taniluyá. Ashes fell in the areas near Morelia, Panimache I and II, among others.
Source : Insivumeh
Photo : Archives