An 8.30 am start and we are off!
It becomes immediately clear how geologically spectacular
the island is. Lava flows over lava flows, lava channels some deeply incised,
a'a' flows, pahoehoe flows, cooling fractures, lava tubes, cones, craters, the
list is pretty long I must say. And I love it!!!!!!
It certainly is 'La Isla Bonita'.
So today I started on the soil gas sampling under the
watchful eye of Samara and Hannah started on the CO2 efflux and
surface temperatures under the watchful eye of Paulo.
Me getting stuck in to sampling for Helium.
The equipment used for soil gas sampling is surprisingly
simple. Syringes, tubes, valves, needles, all medical. Glass tubes with one way
rubber inserts so the gas will go in, but not come out. and a metal rod (a
proof). The proof is hammered in to the ground to a depth of 40cm then a needle
attached to a tube, valves and a syringe, is inserted in to the top of the
proof. Gas is drawn out, then evacuated by adjusting the valves. The gas is
drawn from the soils a further 2 times and each time emptied in to a glass
tube; at 10% of the sites a third sample is collected. The amount of samples
collected at each site can be adjusted based on the location you want to survey
and what it is you want to analyse. Today 35 sites were sampled, totalling just
under 80 little glass tubes for the day.
Some of today's sample sites were close to the coast. Here
we could see the saltpans, the Fuencaliente lighthouse or 'Faro' and Volcan de
Teneguia, the location for the 1971 eruption, the most recent on La Palma.
Faro de Fuencaliente in the foreground with Volcan de Teneguia (the source of the 1971 eruption) behind
There are few contrasts as striking as white salt on black
basalt, interspersed with the reddish colour of the heating basins of a
saltpan. The Fuencaliente saltpans, "Salinas Marinas de Fuencaliente",
are a perfect example of the interplay of colours. A family of master salt
producers built these saltpans in the last third of the 20th century and had
the good fortune to be spared by the lava from the Teneguia volcano, which
avoided the construction as it flowed to the coast.
The Salinas Marinas de Fuencaliente - the saltpans
Today, the salt produced here is of a very high quality, and
great care is taken of the area. The site is also an important stop for
migratory birds, giving the area a biological SSSI (Site of Special Scientific
Interest).
The lighthouse marks the end of the Volcano path, Ruta de Los
Volcanes. Most of this coastal platform was created by the 1677 eruption of San
Antonio and the 1971 eruption of Teneguia. The abrupt nature of the platform
shows where the lava reached the ocean.
The lighthouse is made of Arucas stone, brought to the
island by sea from Gran Canaria. The old lighthouse was a welcome sight to
sailors and travellers alike, but is now used as an exhibition space with a
taller, but less aesthetically pleasing lighthouse taking over the traditional
lighthouse role.
On returning back to our home for the next three weeks, all
the equipment is prepared for the next day. Batteries, GPS and PDA's are
charged, equipment is replenished and some of the equipment is disposed of to
reduce contamination.
The samples are the split according to what they are needed
for. In this case one sample is for Micro-Chromatography (µCG)
.
.
Now it is time to chill, eat and have a beer!
Just outside our little house is a little church where
peaceful singing can sometimes be heard. When we arrived there was the Corpus
Cristi (flower carpet) festival going on which was followed by the Transvulcanica
race.
A very small snippet of the Corpus Cristi displays
Transvulcania winners plaques - this years was added while we were there
Every day is an adventure!
Buenas noches de La Palma!
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