"The heat around the volcano will be with us for the rest of our lives"

The IGN points out that eight months after the end of the volcano's eruption, high temperatures continue to be recorded at various points in the cone and in the flows that could last tens or hundreds of years.

EFE Santa Cruz of Tenerife

The
high temperatures that eight months after the end of the La Palma volcano eruption there are still records in
various points of the cone and in the lava flows they could last dozens, even hundreds of years, points out the National Geographic Institute (IGN).

“This heat will accompany us for the rest of our lives. We have no choice but to normalize the temperatures in an area that has suffered an eruption and respect this environment (...) It is something natural, normal and expected«, warns the IGN volcanologist Stavros Meteltlidis.

Meletlidiswho recently published a thread on social networks where he emphasized the differences in terms of security between the
volcanoes of Iceland and La Palma, has published another in which he tries to explain what happens to temperatures after an eruption.

It details that the
magmacomposed of molten rock, minerals and volatiles, rises from the earth's mantle at a temperature of
1,400ºC and that on its journey to the surface, "for various reasons", it cools down and at the time of the eruption values ​​between 1,100 and 1,200ºC are measured.

Once the eruption is over, in the area of ​​the lava flows the outside is already cold at
"few weeks" in the case of thin flows.

Actually, Meletlidis abounds, the outside is already almost cold since it was installed, but the
molten material below it makes the whole body continue to be over 700ºC.

in the cone
“things are different”since the surface is covered by poorly consolidated material (ash, pyroclasts, slag...) that start at a lower temperature, but a few meters below that material the temperature is about 1,000ºC «and we will be like this much longer » than in laundry.

The IGN volcanologist emphasizes that the
minerals present in the lava have the
ability to store heatand although they crystallize and change, they continue to maintain it.

And since there is no combustion, no mass is lost, so the temperature will drop with
"slow cooling".

Meletlidis points out that the most important mechanism for
chill a flow it is the contact with the air and not the rain as one might think.

The greater the thickness of a flow and the closer it is to the
emission pointthe longer it will maintain temperatures, he stresses.

The question is: for how long?

The answer, according to Meletlidis, is that it depends on the thickness, composition, distance from the emission point, site temperature, conditions with a little
SO2, H2S, CO2... that come from the magmatic body and escape during its "slow cooling".

The expert emphasizes that "the surprise" comes a few meters deep and at the points of the paths that the magma has used to reach the surface or where it has filled fractures and discontinuities, since there are registered
temperatures around 1,000ºC and incandescent material is appreciated.

At this point, he clarifies that when the
basaltic magma at shallow depths or lavaon low surface Above 1,000ºC they stop flowing, so there is "no chance" that this hot rock can "come to life, that is, flow" again.

Also in this case the time
it takes time to cool down This material depends on the composition, the porosity, the path of the magma, the geometry of the body, the temperature of the host rock, the volume of material at a shallow depth and the thickness of the branches or dikes.

On the latter, Meteltlidis abounds in that from the surface to a depth of
between 10 and 12 kilometers there is a network of ramifications and magmatic bodies through which the
heat flow.

In the case of a feeding dam, although the
glow would disappear after a few months, the central part would drop to 800ºC after several years "if nothing changes first".

Meletlidis stresses that based on field measurements, laboratory analysis and numerical cooling models, a basalt dam between
4 and 5 meters that has participated in an eruption needs about 100 years to reach a temperature of 200ºC,
“and we always speak for the part near the surface”.

“Things change a lot in depth”abounds, and gives the example of Timanfaya in Lanzarote, where almost 300 years have passed since the eruptions and the magmatic body is almost 5 kilometers deep and, even so, 600ºC can be measured at 13 meters from the surface.

«If we apply this to La Palma we understand that this warmth will accompany us in the rest of our lives. We have no choice but to normalize the
temperatures in an area that has suffered an eruption and respect this environment. As I have always said, it is something natural, normal and expected », she concludes.

Pedro Sánchez will visit La Palma this Tuesday

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