Great excursions - Slovakia 2015
Two weeks through Slovakia and Hungary with almost 50 stops
Overview map Slovakia and Hungary 2015
The two weeks of the excursion were divided thematically:
In the first week, numerous raw material geological sites in Hungary and Slovakia were studied. Among others, former as well as active deposits, processing industries and areas under prospecting were visited.
In the second week, the tectonics and the regional geological structure of the Western Carpathians were discussed. The different units and their geodynamic development were treated at numerous outcrops across Slovakia.
The students would like to thank Prof. Dr. Juraj Majzlan, Prof. Dr. Kamil Ustaszewski, Prof. Dr. Dušan Plašienka (University of Bratislava) and Prof. Dr. Georg Büchel for the organization. In particular, the students would like to thank GFG Jena de and other sponsors for their financial support.
1st week
The excursion began on September 18 about 50 km west of Budapest with a visit to a former bauxite deposit. Furthermore, a processing plant for quartz sand was visited, which serves as a basic raw material for the glass industry. In addition, a company for metal scrap processing was also visited, as an example of secondary raw materials. The second day began with a visit to an open-cast lignite mine.
lignite opencast mine near Gyöngyös.
This was followed by a visit to a company mining zeolites and another company mining perlite as a raw material for mineral insulating material. On a single day, the former gold and silver mining region near Telkibánya, eastern Hungary (about 60 km northeast of Miskolc) was visited. The mining area is located in the Tokaj Mountains and was exploited from the 14th to the 19th century. The genesis of the deposit, the history of the region and the different mining methods of the different centuries were explained to the students at several localities. On September 21, the excursion was continued in Slovakia. First, a talc deposit was visited, which is currently being exploited. This was followed by a guided tour of a scheelite deposit currently being prospected by a prospecting geologist.
Fluorescence of the Scheelite when illuminated with a UV lamp.
The excursion participants also entered a disused lignite mine underground, where they were given an explanation of the mining process. This was followed by two examples showing the consequences of coal as an energy source: Near a landfill for coal ash left over from combustion, there was an accident in 1965 so that the area below was flooded by the arsenic-containing ash. The floodplain was then covered with loose material. Even today, high arsenic levels can be measured in the "Nitra" river. In addition, depressions on the land surface were and are still being formed in the region due to subsidence phenomena of the mine field.
Prof. Majzlan explains to the students the contamination of a river meadow by coal ash and the remediation concept.
The last two days of the first week were devoted to ore deposits. Near Banská Štiavnica and Banská Belá outcrops of neovolcanites were visited. The visit of several localities around Kremnica followed. A tunnel was entered, an open pit was visited and an outcrop of a rhyolite dome was studied. As a conclusion of the first excursion week a former copper ore deposit was visited in Ľubietová. The mine is visited by many mineral collectors, as very beautiful malachite specimens can be found here. This was followed by a visit to a dump of a gold ore deposit in the Low Tatras and an outcrop of melaphyres near Banská Bystrica.
2nd week
During the second week the different tectonic units of the Western Carpathians in Slovakia were studied at various outcrops. It was started on September 26 with the visit of outcrops of the Meliaticum with radiolarites of the Lower Triassic and platform limestones of the Upper Triassic as well as ophiolites and shelf limestones. In addition, metamorphic rocks (glaucophane schists - high pressure and low temperature) of the Bôrka cover were also visited, as well as the Wetterstein limestone of the Silica cover. These units belong to the Inner Western Carpathians. The Meliaticum is the relict of the former Meliata Ocean, which was closed in the Jurassic to Cretaceous. The Bôrka cover consists of obducted rocks (ophiolites) and the Silica cover of the sediments of the former continental shelf.
Prof. Plašienka (University of Bratislava) shows the tectonic units on the geological map of Slovakia.
This was followed by a visit to the units of the Central Western Carpathians. The students were first shown outcrops of the Gemericum and Veporicum, which form the crystalline basement, and the Muráň cover. The Gemericum has partly overlain the Veporicum and is allochthonously overlain by rocks of the Muráň cover. Among others, granitoids of the basement (Veporicum) and its cover by Mesozoic metasediments (e.g., quartzite, dolomite) were inspected. Then the boundary between the Tatricum and Veporicum was visited, as well as other outcrops of the Tatricum. The Tatricum was overlain by the Veporic unit. Fatricum and Hronicum were thrust over the basement as blanket structures in the Upper Cretaceous. These blanket structures were also studied at other outcrops. On a single day, the sequence of Fatricum and Hronicum cover was hiked in the Little Fatra, about 30 km west of Žilina. The hike started in the Tatricum and was followed by a 16 km long hike through the Fatricum units.
The exposed Dolomites of the Veľký Rozsutec in the Little Fatra.
The last two days of the excursion were spent visiting outcrops of the Pieniny Cliff Belt, which is the boundary between the Central and Outer Western Carpathians. The cliff belt is the relic of the subduction of the Piedmont-Liguria Ocean, which is also called the Pieniny Ocean here. The belt is divided into several tectonic units, most of which are composed of deformed Jurassic and Cretaceous sediments.