Tertiary Magmatism along the Periadriatic Lineament

By Unknown -

Alpenseminar by Verena Frey

On the 18th of May we learnt about Tertiary magmatism along the prominent Periadriatic Lineament. During the previous seminars we discovered that the Periadriatic Lineament represents an important tectonic feature across the Alps and also plays an important role in controlling many surrounding geological processes, including stress release. Curiously, much Tertiary magmatism seen within the Alps appears to be aligned along the Periadriatic Lineament, as can be seen below:


Overview of the Periadriatic Lineament and surrounding Tertiary intrusive bodies, after von Blanckenburg and Davies, 1995


The Periadriatic Lineament formed in response to dextral movement along the European and Adriatic collisional zone and is often characterised by steeply-inclined mylonitic structures. Age dating of the Adamello pluton has helped constrain the age relationship of magmatism to being syn-collision:


Overview of the range of age dating for the Adamello Pluton, after Rosenberg, 2004


The mechanism that resulted in the magmatic activity during the Teriary is thought to be associated to the breaking off of the lower (European) slab during the collision process with the Apulian (upper) plate. This would ultimately result in melting of the broken and descending slab and rising up of the more buoyant melt product. These melt products were then funneled along intricate shear structures of the Periadriatic Lineament. We may summarise this process in the following figures, after Schmidt et al., 1996:

1. Convergence between the European and Apulian Plates:




2. Slab break-off, melting and magmatic uprising: 



  


Location: Jena, Germany

Comments

Post a Comment

Popular posts from this blog

Paleogeography of the Alps

By Unknown -
Image
Alpenseminar by Taufeeq Dhansay The formation of the Alpine Mountains can be broadly defined by the convergent movement of several continental plates and the associated opening and closing of oceanic basins. The science of Paleogeography aims to travel back in deep time and figure out how these different plates would have moved, and ultimately collided to form these magnificent mountains.  The protagonists Firstly, we should identify the main players (i.e. plates) in this story. This includes the larger African/Nubian and European plates, and the smaller Adriatic/Apulian and Iberian Plates. Below is a figure of the present-day alps and how its underlying tectonic units fit together: Broad overview of the major plates associated with the Alpine Orogeny, after  Handy et al., 2010 Importantly, zones between these plates (i.e. demarcated by darker colours on the above map) represent regions that, in particular, experienced varying levels of tectonism and/metamorp
Read more

Active Tectonics in the vicinity of the Alps

By -
Image
Alpenseminar by Benjamin Schmitz On the 27th of April we had a presentation on the active tectonics across the Alps by Benjamin Schmitz . To begin, we considered the tectonic setting across the Eastern Mediterranean by looking at the most recent Paleogeographic reconstruction of the Alpine orogeny. Recent Paleogeographic setting of the Alpine orogeny, after  Handy et al., 2015 The effect of the orogenesis linked to the indentation of the Adriatic Plate (brown on the above figure) into the European Plate (blue on the above figure) resulted in the formation of several faults and collisional zones. We may now consider: What tectonic effect remains? To better elaborate on this question, we may now consider the GPS velocities across Europe, Asia and North Africa, which is further associated to Nubia-Eurasia-Convergence: GPS-measured relative plate motions between the African and European/Eurasian Plates, after  Facenna et al., 2014 Importantly, this
Read more

Historical and Catastrophic Landslides

By Unknown -
Image
Alpenseminar and Blog post by Thomas Biehl On the 14th of May we had a presentation about really impressive and destructive landslides in the Alps. These landslides are generally related to large earthquakes and there are few examples that we may consider here: 1. Dobratsch - Carinthia In 1348 a destructive earthquake occurred near the town of Villach on the Austrian/Italian border. This earthquake resulted in several landslides along the 2166 m high Dobratsch massif, which lies atop the Periadriatic Lineament. Overview of the Dobratsch landslides, after  Lenhardt, 2007   The largest of these landslides was known as the "Rote Wand". This caused the destruction of a dam and the flooding of the whole Gail River Valley. Overview of the regional structure of the Dobratsch Mountains, after Stefan et al., 2004 2. Köfelsberg - Tirol Rapid Alpine deglaciation during the Holocene, approximately 9000 BC, resulted a massive landslide near th
Read more