Volcanic eruptions can be devastating; damaging
infrastructure, spoiling crops, and leading to injuries and loss of life.
Volcanic monitoring can help mitigate against disaster, ensuring the safe and
timely evacuation of those living in the vicinity of a volcano on the brink of
eruption. Much of this monitoring is now conducted remotely, using satellites
and systems that send information back to where the data is processed. However,
some sampling methods still involve people going on site and getting up close
and personal with volcanic hazards. It is vital that these volcanologists are
well protected and wear the correct safety gear to keep safe.
Volcanologists
take samples of gas at a fumarole. The yellow on the rocks is sulfur from the
cooled sulfur dioxide (Wikimedia,
accessed 8/6/2020)
Gas sampling is a very important type of monitoring. When
magma begins to rise to the surface its pressure decreases, this releases gases
into the atmosphere, including carbon dioxide, sulfur dioxide, hydrogen sulfide
and water. This process is known as degassing. The gas is released at chimney
like structures on the volcano known as fumaroles. Sampling gases can be
hazardous for numerous reasons. There is a chance of asphyxiation and irritation
to eyes, skin and the respiratory system. The gas can also be extremely hot, with a
high risk of burns. For these reasons, when conducting gas sampling volcanologists
usually wear protective clothing such as full-length trousers and long sleeve
tops and gloves. Sometimes they also wear gas masks. The collection device is
at the end of a long stick so that the volcanologist does not need to get too
close to the hot gas.
Volcanologists also study lava as it flows out of a volcano.
From this, they can find out about the chemistry of the molten rock and learn
more about what is going on deep underground. They can also analyse samples
taken from further down the flanks of the volcano, which may have erupted some
days previous, to work out how the magma has evolved after eruption.
It is
difficult to comprehend just how hot lava is. When it first erupts it can be
above 1,000oC, even at its coolest it is still above 600oC.
Obviously, this is very hazardous to anyone who is working to collect samples. Volcanologists will often wear special full
body suits, which are heat resistant and look a lot like a space suit. They
will wear gloves and usually a mask or visor to protect them from lava
splatter. Thick soled boots are also
necessary as the ground they are walking on can often be hot..
- Here is a scientific video explaining why lava samples are taken and demonstrating how it is done: Lava Sampling on Kilauea, Hawaii
- Here is another more dramatic video showing the dangers of lava sampling, even in full protective gear: Scientist gets too close to lava lake!
With improvements in technology the need for humans to
conduct direct sampling will continue to decrease. Increasingly gas sampling is
being conducted by specialist instruments either mounted on site or on
satellites. In future, it is likely that lava sampling will be conducted by
remote controlled robots. Although, for some volcanologists it may take some
excitement away from their jobs, this will lead to much safer scientific data
collection.
Useful activities and websites:
- For hands on activities relating to designing protective clothing for volcanologists, have a look at our Monitoring a Volcano WASP STEM package.
- For more information on how volcanoes are monitored, read our Volcanic Predictions blog.
- To learn more about gas sampling methods and the hazards associated with volcanic gas have a read through the USGS Volcano Hazards Program.