Monday, January 26, 2015

A winter day, somewhere in Navarra


This time I will not say where I've been, because I am going to show you 2 species in danger of extinction, but I think that will be many people with the tracks that I going to give you, who will recognize the place.
If someone  want to visit it, I'll be happy to do so.

Nummulites
Lets begin with the composition of the rocks of the place; as you will see, they are full of fossils of some 55 million years ago and  marine origin. They are called Nummulites, and is a composite Latin word (nummus / coins, litos / stone). If one sees flat, they look like coins with concentric circles, but if it turns out that the bug (not an animal but a unicellular be called protist) was on side when fossilized, or broke, then they are more elliptical.
They are foraminifera,   http://en.wikipedia.org/wiki/Foraminifera a kind of macroplacton, swimming in the waters of the prehistoric sea that disappeared when the Iberian peninsula was built against the European continent.
Among its concentric circles, sprouted a number of something similar to a little hairs with which they fed.
The main of the limestone of  the  Pamplona/Iruña basin, looking to the south, are made with skeletons of trillions of these beings (Alaitz and Sarbil ranges, pilatos balcony, above Urederra fountainhead, ..)
I have found this very good link about these things:(in spanish)

http://www.geoparquepirineos.com/contenidos.php?niv=&cla=_2OA1CD0KM&cla2=_2OB01HU8N&cla3=_3MD0KXM4T&tip=3&idi=1

The second clue corresponds to the river that flow in this area. Its waters have been carving in the rock several circular holes called potholes. Sometimes,  a stone  is trapped by the current in an imperfection of the rock, as a small hole, and with the water movement this stone begin Smoothing and getting bigger the hole until it can reach several meters in diameter.

http://es.wikipedia.org/wiki/Marmita_de_gigante

Pothole with the dead trout
In this small pothole beside the river which coming rise due to the snowfall of yesterday, a poor troutfound the death. I do not know if the rise would have pushed into the pothole which later it could not get away, or died of old age after a full life, but the truth is that was recently died there. Gills were still red, but the skin was beginning to fade.
I put my hand to hand as size reference.





A few meters we can see a small seam between two limestones  of crystallized calcite. When these rocks were forming, hot water and great pressure fill of lime circulated through a crack, until calcite began to accumulate on the walls of the crack, filling them and sealing like cholesterol in our arteries. This procedure is the same when we found a vein of copper, silver, gold and many other minerals, but in that case, would be other kinds of rocks which would have to look not in sedimentary rocks, but in metamorphic, and almost always attached to quartz.



Calcite crystals 


Latest clues!
It is the Bearded Vulture foraging territory, abundant colonies of griffon vulture, and now in winter, a rare bird jewel, the walcreeper (Tychodroma muralis)!


Bearded vulture (Gypaetus barbatus)
Griffon vultures (Gyps fulvus)

Wallcreeper (Tychodroma muralis)

This beautiful Wallcreeper was takin benefit of the sun's rays to eat the few bugs that appear in the heat rock or  refuge in the numerous cracks and holes.

So, although it seems that few things to see in winter, actually in all seasons there are many things to see



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