- DFMorvan solved the first part of the Name that Lava in a very short period of time. So i guess it was not very hard. I prepared the post in a hurry to provide some weekend entertainment and did not have much time to search around. Sissel and Chyphria got the other two points.
Here is the original image which Sissel detected correctly.
And a closeup shot nearby and from the same link showing the rocks in more detail.
Volcanic activity in Styria, Austria
Two Geological maps of Styria. The right one by Iris also showing recent earthquakes The other one comes from the best paper on the topic pointed out by chyphria and Kelda .
Some month ago, the question came up if there are any volcanoes to be found within the Alps. The hilly countryside in the southeastern part of Styria is not exactly “the Alps” but it lies very close and it is of the same origin as the Alps. The northafrican plate pushes against the europen plate and this caused the alps to be raised as well as some volcanic activity in Styria. Styrias volcanoes are part of the Transdanubian Volcano region ( Wikipedialink in German) This region stretches from Slowenia over Karintia and Styria to Burgenland and then well into Hungary.
Here is an image of the map found on the german site VulkanLand
The original map is interactive: http://www.vulkanland.at/de/steirisches-vulkanland/Vulkane/Karte/?template=popup
There seem to have been 2 phases of volcanism. One way back in the Miocene dating back around 17 million years and a later phase in the Gelasium in Pliocene ended around “only” 2 million years ago. The first phase was an acid volcanisim and produced mostly shield volcanoes like the ones in Gleichenberg. Many of those ancient volcanoes were only discovered when drilling operations took place, in the attempt to search for oil. The later phase produced mostly basic Vulkanites and you find old remanants in the countryside mostly in the form of tuff cones. The rest has been eroded over the milenia.
The european plate subsided under the african plate, the rocks melted and emerged through cracks. So what happened then, was subduction volcanism, which can now be seen in many volcanoes of the famous pacific “Ring of Fire”. ( Renatos “favorite!”) One example of the older eruptions is the “Gleichenberger Kogel”. An eruption over a period of 5 million years. Only the peaks of the ancient volcanoes are still standing out in the landscape, the rest was covered up with deposits. If you consider how much of those deposits are needed to fill up whole valleys in between the volcanic cones and this was done in a few million years, it shows how distinctively a landscape changes in just a few million years, especially if you keep in mind, our earth is 4,52 billion years old. So there was, most likely never a dinosaur standing in the exact spot were you now hold your BBQ in your backyard.
Around 40 volcanoes once dominated the southeastern parts of Styria.
The quarry in the “Schaufelberger Graben” needs an extra mentioning because one can find Quartztracyte there, a rarer version of the common trachite.
The rock of Riegersburg is a diatrem an old volcanic vent filled up with Basalt. The outer layers erroded away and only the hardest pieces were left standing.
This Image is originally found in the german paper: Geomagnetische Untersuchungen ...
Now there is the castle on top in all its glory.
A short hirstory of the “Riegersburg” the castle also called the last bastion of christianity because it never fell to the invading turks: The first castle being built on the volcanic rocks was called „Ruotkerspurch“ named after its building father Rüdiger von Hohenburg in 1138. Later it was extended in Renaisance style. The one woman who had most influence to the apperance of the castle was Baroness Katherina von Galler who made the greatest styrian fortress of the 17th century. Nowerdays the castle is one of the mayor tourist attractions of Styria. People can visit the fortress and some original rooms and get informed about the witch-hunt. The rocks can be climbed with several fixed rope routes.
Schilcher is a rosé wine speciality of souther Styria produced from the grape variety “Blauer Wildbacher”. It may ony carry the name if it was produced in this region, which is the smallest wine producing region in Europe. Many austrian wines are more acidic than mediteranian wines and so Pope Pius said: “They served a rosé vinegar which they called Schilcher.” Many of those wines may have been rather of little quality in oldern days but the quality improved lots and when i studied in Graz and made excursion to the southern styria wine country, we had some delicious samples of Schilcher. It is very typical for people living in Styria to head out into the countryside in autumn and drink the new wine or the not- quite – ready wine called SchilcherSturm with roasted chestnut. Be warned. Sturm tastes more like a grape juice, is really good but gets to your head easily and does wonders to your digestion.
Papers for further inquiry:
- The Neogene of the Styrian Basin – Guide to Excursions by Martin Gross, Ingomar Fritz and others. Found in 2 locations. This one of the University in Graz pointed out by chryphia and this one of the Landesmuseum Johanneum pointed out by Kelda.
- Tectonic development, morphotectonics and volcanism of the Transdanubian Range: a field guide. Laszlo Fodor, Gabor Csillag; Karoly Nemeth, Tamas budai, Tibor Cserny, Ulrike Martin, Karoly brezsnyansky and john Dewey.
- Das Eruptivgebiet von Gleichenberg in Ost-steiermark by Artur Winkler
- Kohlefazies und Sedimentologie der Eibiswalder Bucht (Miozän, Steirisches Becken) by Wilfred Gruber, Siegfried Hermann, Reinhard Sachsenhofer &Karl Stingl.
- Zur Geologie des südweststeirischen Tertiärbeckens by A. Winkler-Hermaden
- A Stratigraphic Enigma: The Age of the Neogene Depsoits of Graz ( Styrian Basin; Austria) Martin Gross, Mathias Harzhauser, Oleg Mandic, Werner Piller & Fred Rögl
- Über die sarmatischen und politischen Ablagerungen im Südostteil des steirischen Beckens. A. Winkler.