A Tour in Geology – Gneiss

I offer you  a little tour in geology with Devin Denny – a wandering geologist.

In this walk, Denny takes us into a canyon, located near the town of Golden, Colorado. This is a great opportunity for you to get to know  geology  in details, with all the knowledge that Front Range, the foot of the Rocky Mountains, offers.

In similar canyons, through which a river stems, various  volcanic and metamorphic rocks are located, all from the Precambrian Period. The rocks are highly deformed due to the force, which led to erection of the Rocky Mountains. There, one can see large, old, stone pieces – memories of the magma, that has flown during the above mentioned period.

In some places, one can see veins, which appear to be fairly intact – an indication that they are still young. However, in other places, they seem quite deformed. It is obvious  that some kind of force has impacted those volcanic igneous rocks, once their formation was done.
Together, we can observe what has happened with the rocks: the way they were formed indicates the way in which this valley was formed.
Many of the igneous rocks, which can be found in the valley, belong to the category gneiss. Those are highly deformed rocks, due to the heat and the pressure exerted in the process of their formation.

Denny presents a wonderful model of gneiss, on which cracks are clearly visible. The way in which they are cut and the direction they face offer some valuable information about the rocks. Watching this deformation, we can definitely determine that the gneiss rock seems to have been curled like an accordion. From here follows that it has been subjected to a strong pressure, that has pushed it in the given direction.

In conclusion, it can be said that this is a highly deformed rock piece, completely different from the one that it was in the beginning. Most likely, this is granite gneiss or diorite gneiss – a volcanic rock, created by the hot lava. After the lava has cooled, the rock has formed. Later, during the erection of the Rocky Mountains, the rock has been malformed, which has led to the creation of the modern gneiss, as we see it.

Towards the end, Denny reveals to us that some relatively young rocks were pushed into some of the old volcanic rocks. This has occurred thanks to a more recent magma, which has wedged itself into the cracks of the old stones, and then has cooled down. Exactly in these newer and younger volcanic and granite rocks, which have come to the surface, many minerals and elements have congregated. This has led to the emergence of heavy metals, that attract the attention of generations of gold – diggers.

Hopefully, you have enjoyed our tour in geology and it has enriched your knowledge about gneiss, the oldest stone in the world, and its formation.

If you want to learn more about gneiss and where it can be bought in Bulgaria, please, take a look at our website and scan through the other articles we have and the products that we offer.