Wednesday, January 23, 2019

Columnar Basalts

After hearing all sorts of explanations about their origin, today I would like to talk about columnar basalts.
Here in Sicily we have several outcrops of this kind of rocks, like the ones at Alcantara river, at Lachea island or along the Timpa of Acireale, in Aeolian Islands and Pantelleria.

 
Above: Timpa di Acireale and Alcantara Gorges.
Below: Acitrezza' Stacks and Timpa di Acireale.


These morphologies are typical in lavas of basaltic composition (therefore with percentages of SiO2 between 45 and 53%) that during cooling have fractured in a very particular way due to thermal contraction.

This type of fracturing, which isolates long polygonal (often hexagonal) columns (hence the name "columnar basalts") can be observed when large masses of lava are cooling down.
The portion that cools first is obviously the outermost part, such as the surface or the base or even the sides of this mass of lava and it is here that these contraction fractures are formed, leading to the growth of a polygonal mosaic on the surface. These polygonal cracks, interconnected to each other, propagate towards the central portions of the lava mass together with the cooling, thus isolating blocks that we will see as polygonal columns when the lava formation will be eroded and exposed.
The phenomenon, at least in its former stage, has been observed from the 1960s in Hawaii's crater lava lakes (lava pools at 1200 ° C almost one kilometer wide and up to 80 meters deep!).

So, all of these columnar basalts have been created when we have a big mass of lava slowly cooling down (e.g.: a crater lava lake; a lava pool along a lava flow; an injection of lava into the still plastic sea floor sediments).

Disclosing the temperature of columnar jointing in lavas Anthony Lamur, Yan Lavallée, Fiona E. Iddon, Adrian J. Hornby, Jackie E. Kendrick, Felix W. von Aulock & Fabian B. Wadsworth  Nature Communicationsvolume 9, Article number: 1432 (2018)
Insights:

The formation of columnar joints produced by cooling in basalt at Staffa, Scotland

Disclosing the temperature of columnar jointing in lavas


Wednesday, September 14, 2016

Taormina Trip

Today the sea was calm and the weather was not too hot, perfect to explore every rock corner on the Taormina coastline! Nice small group from three different countries!







Monday, August 22, 2016

August: season's end or just a break?

After a short break for the two central weeks of August we start again to travel around and along the South-East coastline of Sicily, guiding paddlers and hikers. This working year (not only as a guide) has been particularly intense and the break in the summer heat has been more than welcome. But, judging on the bookings and e-mails we started again to answer to it looks that the season is far to have ended. Here few pictures from the first week of August, just days before the luggage packing for our hoped holiday!

underwater grassland
sea life discovery
crowded beaches, empty seas
Mt. Etna lava tube

Mt. Etna volcano landscapes. 

Taormina's Blue Cave
Taormina
Columnar Basalts in Acitrezza






Wednesday, May 4, 2016

PAGAIA AZZURRA

Quest'anno anche la Federazione Italiana Canoa Kayak è entrata a far parte del framework Euro Paddle Pass (EPP)! Adesso i corsi tenuti dagli istruttori FICK secondo gli standard del nuovo sistema di Certificazione Nazionale Pagaia Azzurra, sono riconosciuti e validi in tutti i paesi aderenti: Danimarca, Francia, Germania, Inghilterra, Irlanda, Italia, Norvegia, Slovenia, Svezia.
Adesso che lo standard italiano per l'insegnamento delle tecniche del kayak da mare si è allineato con quello europeo sarà possibile esibire all'estero una certificazione riconosciuta, si potrà completare la propria formazione, nella propria disciplina, in uno qualsiasi dei paesi aderenti all'EPP, oppure si potrà proseguire in Italia la propria formazione iniziata all'estero. Sarà inoltre più semplice affittare canoe o kayak presso centri italiani ed europei ed iniziare un percorso formativo necessario per accedere al programma di formazione per i Tecnici FICK.
Speriamo anche che, come è avvenuto in altri paesi che hanno aderito al progetto EPP, il numero dei praticanti possa essere incrementato!




This year also the Italian Canoe Kayak Federation has joined the EuroPaddle Pass framework (EPP)! Now the courses delivered by FICK instructors according to the standards of the new National Certification Pagaia Azzurra system, are recognized and valid in all participating countries: Denmark, France, Germany, England, Ireland, Italy, Norway, Slovenia, Sweden.
Now that the Italian standard for the teaching of the sea kayak skills has aligned itself with the European ones, the paddlers will be able to exhibit abroad a recognized certification. You will be able to complete the training, in your own discipline, in any of the EPP member countries, or you can continue in Italy your education started abroad. It will also be easier to rent a canoe or kayak from Italian and European outdoor centers and to start a training program required to become an instructor.

We also hope that with this, as has happened in other countries that have joined the EPP project, the number of paddlers can be increased!

Sunday, November 29, 2015

November 29

Well, it's not like summer but it's a great weather.
This morning I made two laps: the first with a young couple from Germany, the second - a bit shorter - with two younger characters that wanted to learn too quickly...
Here few pics of this nice day.

 
 

Saturday, August 1, 2015

Full Moon Night Paddling

Having temperatures going even above 37°C during the day, a night paddling becomes almost mandatory!
With a bunch of friends we went out to look for a fresh full Moon night exploration of the rocks in front of the harbour of Acitrezza.
The current was going northward - almost 2 knots ! - and there was a nice swell going southward, giving us some fun behind Lachea island in shorth and steep waves in the darkness!
My wife was finally back in her kayak after a very long time and my doughter was playing with me in a double, screaming in the dark "my father is crazy!".
We all and someone more had a final "pizza&beer" in a lovely terrace above the sea. It was really great!