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€UROCK THE ELECTRONIC NEWSLETTER OF THE OPEN UNIVERSITY GEOLOGICAL SOCIETY MAINLAND

MAY 2010

BACK FROM THE OUGS AGM This concern is actually one that we discuss In April I went to the AGM and Committee within our Branch Committee along with how to meeting in Coventry, where among the other recruit new members. branch organisers I was happy to meet some In this newsletter I would also like to thank the “old acquaintances” from former memorable committee, Marion, Mike, Terry and Dave for all field trips and symposiums. I got a warm wel- the support and work they did since last January. come as the committee was pleased to see that We communicate on a regular basis via email and the European Branch is still an active branch share our ideas and comments. As it is difficult to and wants to stay one. meet most of you on trips, don’t hesitate to get in How to get in touch with people interested to join touch with us if you want to share information our Society was one of the topics that was men- about an event or about any other matter, tioned. With the demise of summer schools, it is geological matter of course! more challenging to get in touch with OU students I wish everyone a sunny summer and maybe I will and, at the same time, there might be a greater ne- meet some of you in Swansee, cessity to offer them the opportunity to join field Elisabeth d’Eyrames trips.

If you would like to get in touch with the A NOTE FROM THE EDITOR committee, simply drop us a line: Dear readers, > Branch Organiser: Elisabeth d'Eyrames [email protected] in this issue of the OUGS ME newsletter, we would like to introduce two new concepts. > Treasurer: Mike Molloy [email protected] First, we would like to give each of our branch members some space to introduce her- or himself, > Newsletter Editor: Marion Seitz in our “members’corner”. Eileen and Neil Lawley [email protected] are the first to do so and we hope that in every fu- > Librarian> Terry Warrington ture issue of the newsletter, one or two further [email protected] branch members will tell us a bit about them- > Webmaster: Dave Kopsc selves. So don’t be shy, send us your introduction, [email protected] at your leisure. Your text could be like Eileen’s and Neil’s or it could be very much different. After all, our branch is a very diverse one and this IN THIS ISSUE could (or should?) show in the members’ corner. The second novelty comes under the heading of The Valley and the Bayerischer Pfahl....1 “the science behind the news”. Here, we take a Introducing Neil and Eileen Lawley ...... 3 look - on occasion - at a major issue that has been covered in the media, if it has somehow been Ash clouds - it’s all up in the air...... 4 -related. Of course we don’t just want to Articles and Information from other re-tell the story but rather want to say more about branch newsletters ...... 6 the geological and scientific facts behind it. In this issue, Terry Warrington talks about the infamous The Jura weekend: archaeology and geology....7 ash cloud that has caused some trouble for a few Post-exam field trip: programme and weeks. background ...... 9 Marion Seitz THE REGEN VALLEY AND THE BAYERISCHER PFAHL A bike trip in / by Mike Molloy

My bike trip with Christian, Sigi and Rolf this out to be a good choice. There was a festival of folk year, was somewhat shorter than usual and ear- music in Regen over the Whitsun holiday, with over lier in the year. Our route was from Bayerisch 400 folk-music groups expected from the German Eisenstein to Regensburg, some 177 km along the speaking regions, the and even Swe- valley of the river Regen. We met at the Munich den. The festival beer they had brewed for the occai- main station on Tuesday, 18 May, in good time to sion was excellent. take the DB regional express from Munich to On Wednesday 19th, our planned etappe was 58 km Plattling, where we changed to the local private from Regen to Chamerau, via Viechtach. The tour railway, the “Waldbahn”, to take us to Bayerisch guide-book warned us that the 30 km or so to Viech- Eisenstein. tach were going to be difficult. This could qualify as Our traditional “second breakfast” of Regensburger the understatement of the year, they were brutal, sausages, “Butter-Bretn” and beer was delayed until even if we managed them without rain gear. Rain after Freising.That didn”t help to improve the gear became necessary as we entered Viechtach, weather, although all of us had reached Munich sta- which was also the first time that we had seen the tion without rain gear, things were deteriorating visi- river since leaving Regen. After a break for lunch, bly. The weather in during early we headed towards a large outcrop of quartzite of May, is dominated by what are known as the what is known as the Bayerischer Pfahl, which is “Eisheiligen”, these are the Saints’ days starting with one of the most significant Geotopes in Bavaria. St. Marmetus on the 11th of May and ending with St. Sophie on the 15th of May. Frost and snow are not only possible during this period, they frequently occur. This year, in Upper Bavaria, the “Eisheili- gen” manifested themselves as being wet and cold, with temperatures around 5° C. Things had not changed by Tuesday 18th, it would seem that “Cold Sophie”, as she is affectionately known, had forgot- ten to declare the freeze over. Bayerisch Eisenstein lies at some 760 m altitude in the Bavarian/, it is the border town between the Czech Republic and . This is reflected by the state border dividing the railway platforms into two halves. This is no problem today, but it did create some difficulties during the Cold War when both the platforms and the waiting room The is delineated from the Saxo- were separated into two halves by iron chains, run- Thuringian and Moldanubian tectonic zones to the ning across the border-line. The station also boasts west, by 3 major, over-lapping, reverse normal two station restaurants and we retired into the Czech faults. These are the Franconian Lineament, which restaurant to discuss our options over a plate of we shall be visiting during the OUGSME 2010 Post- tastey “Gulasch and Bohemian dumplings” and a Exam Field Trip, the Bayerischer Pfahl and the glass or two of genuine Budweiser beer. In the end, Fault. The faults mark the line of the we decided to continue the trip as planned. between the Bohemian Massif and the Saxo- Rain gear was now very necessary as were gloves Thuringian and Moldanubian tectonic zones. The and winter fleeces, but the track was good, well sign- zones were assembled in the Late Devonian to mid- posted and predominently downhill for the 30 km or Carboniferous, during Variscan orogeny. Around so to the town of Regen, where we found accom- Viechtach, the throw along the fault caused the modaion in the “Brauerei-Gasthof Falter”. It turned to be uplifted some 400 m, rela- arrived by Porsche coupé, accompanied by the tive to the Bohemian Massif. The fault was probably “Fuerstin” on her Harley-Davidson. activated more than once. Hydrothermal fluids enter- The stretch on Day 4 was deliberately kept short, ing the fault at depth caused the quartz present in some 30 km, to give us time to do some sightseeing the rocks to dissolve, as the fluids ascended, the in Regensburg before taking the train back to quartz crystalized out, filling the fault with a seam of Munich. Rolf had been nominated our guide around quartzite, up to 100 m wide and over 150 km long. Regensburg, he originates from Kehlheim not far Subsequent erosion has left the more resistant away, and knows the town well. He lead us initialy quartzite seam exposed along the fault, usually only to the “Wurstkuchl” for one of their famous apparent as a ridge of higher land, but outcrops of up “Bratwurst and Sauerkraut” “vespers”, where the to 40 m in height occur, which are a paradise for rest of the programme was fixed. rock climbers. Sir Norman Foster described Regensburg as “one of The colloquial name “Teufelsmauer” or “Devils the most beautiful cities in the world”, something Wall” seems to be more appropriate than “Bay- which the city gratefully quotes on their website. He erischer Pfahl”, as “Pfahl” is the German expression is not alone with his opinion, Regensburg was added for “post” or “stake”. The name probably originates to the list of UNESCO World Heritage Sites in July from the Latin expression “pallidus”, which means 2006, the centre of the old town consists of around “pale” in English or “fahl” in German. 1,000 authentic and well preserved historical build- We cycled along a road some 100 m from the out- ings. crop, just as the weather reached a climax of misery. Our first visit was to the “Bishop’s Court” now an To get any closer would have required dismounting elegant hotel and restaurant, the Bishop’s Court is and pushing our bikes up a short but very sharp adjacent to St. Peter’s cathederal. The cathederal has slope to get any where close to the outcrop. We re- a long history dating back to about year 730, a fire in sisted the temptation and continued towards Cham- 1273 ncessitated rebuilding and extensive additions erau, as we still had some 30 km to cycle and we and alterations were made up to 1828 when King were not sure how difficult this stretch was going to Ludwig I decreed redecoration in Gothic style. be. In the end, the track lead along a disused railway Maybe the most important features in the cathederal embankment, always welcomed by bikers, independ- are the mediaeval stained-glass windows, the win- ently of the direction of the slope. We were lucky dow depicting St. Peter dates from around 1320- and a 4-5 km downhill run took us into Chamerau, 1330. The artificial lighting in the cathederal is kept which compensated somewhat for the earlier torture. subdued, emphasizing the brilliant colours and work- Our accommodation in the Gasthof-Metzgerei manship of the stained glass. Recently, a new organ Baeckerwirt was excellent, if you can’t find a brew- has been installed, alledgedly the tallest eclesiastical ery with accommodation, a butcher is a good alterna- organ worldwide. tive. Our tour then took us through numerous narrow On Day 3, the route followed the river through some roads and eventually back to the “Wurstkuchl” very picturesque country. Not only are the quartzite where we had left our bikes. By now even the Sun outcops aong the “Pfahl” a paradise for rock had reappeared, so we carried out our tour debriefing climbers, the water meadows along the banks of the in the sunshine over beer and potato soup before river Regen are a paradise for storks. The meadows heading to the station for our train. were still in full bloom and for much of next 90 km Our route took us past the Thurn and Taxis Palace or so, access to the meadows was restricted from areal and St. Emeran’s church, where we stopped 15th March to the 15th of October each year, which briefly. St. Emeran’s was decorated by the Asam accounted for the abundance of storks nests visible brothers, Cosmas Damian and Egid Quirin Asam, in every settlement we passed through. Our goal on who were responsible for the internal decoration of a Day 3 was the “Gasthof Marienthal” which we number of outstanding late baroque churches in reached without having to resort to rain gear. The Bavaria. Our first evening meal on the Post-exam “Gasthof” served “Thurn and Taxis” beer and it had field trip will be in the “Asam Schloessl”, Cosmas been a favourite visiting place of the deceased Damian’s mansion in Munich-Thalkirchen. “Fuerst of Thurn and Taxis” in the summer, he Mike Molloy INTRODUCING NEIL AND EILEEN LAWLEY Marion has asked us to write a short introduction pay for her OU courses that the other students won- of ourselves for the Newsletter so apologies to dered who he was as he never did any lab work. those of you who already know quite a lot about Eileen first came across the OUGS at SXR260 Sum- us. mer School and was not sure about joining a UK- We met at Liverpool University a hundred years ago based society but the Mainland Europe branch has when we were both studying Physics. Neil went on just been formed and after reading some of the to do research on a 12 MeV Van de Graff generator Newsletters she was given and hearing about so measuring the half lives of Calcium 42 and 44 (a few many field trips she decided to join up in 2001. So nanoseconds), while Eileen undertook some palaeo- here we are after field trips, AGMs and Newsletter magnetic research on lavas from Iceland and Ireland. articles later. We actually drilled holes in the Giants Causeway if We left the Netherlands in our boat when Neil retired you ever come across them. and now we have reached Mallorca. We still return Neil joined Philips and Eileen began a career in de- home during the summer and winter months and for veloping computer systems which was interrupted medical appointments as well as OU exams. We from time to time by Neil’s career moves. We moved have seen a to the Netherlands in 1988 and after being diagnosed lot of geol- with rheumatoid arthritis in 1998 Eileen was unable ogy on the to work and after a year or two getting used to her way but I condition decided to begin OU studies in 2001, start- think that ing with S260 after many “government health warn- my favourite ings” about starting with a level 2 course. At first she formations did not really intend to take many courses or study are made of for (another) degree but was persuaded to take the . We exam and was inspired by the introduction of the are also in- BSc in Geosciences to study for this degree. Most of terested in birds, plants and sea life and also visit as the courses required for the this degree were ones many churches, houses, castles, art galleries and mu- that she was interested in anyway and a degree in seums as we come across them. Geosciences would be some atonement for giving Eileen has just finished S104 which is needed for a her geologist supervisor at university a hard time Geoscience degree and has tried to encourage other when he was trying to explain some geology to her. students to carry on studying geosciences and join It all seemed to be far to “fuzzy”’ compared with the OUGS. The Summer School SXR103 will be her physics. last course for a degree. Hooray! The OU arranged for a helper during the SXR260 The Netherlands is rather flat and watery. Our home Summer School and when Neil retired in 2002 he ac- is near Eindhoven companied her on Summer Schools. Eileen had which is 18m taught him so well in order to “earn” some income to above sea level and we actually live in the Moun- tains of Son, among sandhills about 5m high. We thought you might be more in- terested in some photos of our sail- ing travels. ASH CLOUDS - IT’S ALL UP IN THE AIR About the icelandic volcano that kept us busy We all know that from mid April 2010 consider- Eldfell, on Heimaey, to the southeast. If you are the able disruption to aviation took place not just in same vintage as me you perhaps remember the Europe, but spread itself around the globe. So Heimaey eruption in 1973. who or what was the guilty party behind this Eyjafjallajokull’s first recorded eruption was in 920, event? 1612, and again from 1821 to 1823 when it caused a Just in case anyone was not reading there papers or glacial lake outburst. It is known that the volcano watching television the source of the disruption re- has been periodically active for the last 800,000 sides in Iceland and has been around for about years. 800,000 years. The name of the guilty party is the It quietly came into life again on March 20 this year, Eyjafjallajokull volcano. causing some 500 local people to be evacuated The main crater of this volcano is about 3 to 4 km in briefly. But that was nothing to what occurred in diameter and at a height of 1,651 metres, the crater April, it erupted again but this time ten to twenty rim has three main peaks, being (clockwise from the times more powerful and it’s still going. And as they north-east) Guonastein, 1500 metres, Hamundar, say, what happened next is history, the atmosphere is 1651 metres and Gooasteinn, 1497 metres. The south full of ash. face of the mountain was once part of Iceland’s At- The Geology lantic coastline, from which, over thousands of years, the sea has retreated some 5 kilometres. The First some background information, the nature of a former coastline now consists of sheer cliffs with volcanic eruption is largely determined by the vis- many waterfalls, of which the best known is Sko- cosity and gas content of its magma. Low-viscosity gafoss. The volcano’s crater lies underneath the Ey- magma will be easily extruded as lava, for a more jafjallajokull ice cap which cover’s an area of around viscous magma the deciding factor in the degree of 100 square kilometres. explosiveness is its gas content, because a viscous magma by itself cannot be explosive. Viscosity is de- The volcano is fed by a magma chamber under the termined by the silica content, basaltic lava contains mountain, which derives from the tectonic diver- about 50% silica and has low viscosity, rhyolite lava gence of the Mid-Atlantic Ridge. It is part of a chain contains more than 65% silica and is very viscous, of volcanoes stretching across Iceland. Its nearest ac- andesitic lava has around 60% silica. Generally rhy- tive neighbours are Katla, to the northeast, and olite and andesite are produced at subduc- tion zones, basalt at mid-oceanic ridges. Since Iceland sits on top of a mid-oceanic spreading ridge we would conclude that its volcanoes would be high in basalt and have low viscosity. But to complicate things Iceland also sits over a Mantle Plume, this brings to the surface magma whose source lies at depths in excess of 400 Km. this interaction of two types of volcanism has created the Island of Ice- land, which has some 130 active volca- noes. And as we have all seen recently they can be very explosive and conform more to what is called a Plinian-type ex- plosion, here extremely viscous gas filled magma is blasted out of the vent at nearly twice the velocity of sound, ejecting tremendous volumes of pyroclastic material and can send the ash cier. Researchers at the University of Iceland esti- cloud up to 45 km into the stratosphere. The eruption mated that there was around 1cubic kilometre of ice of Mt Vesuvius in AD 79 was of Plinian type. in the summit crater and about 25% of this was The Eyjafjallajokull volcano is a Strato volcano or melted in the first two days of the eruption. This in- composite cone; these are much larger than the sim- teraction of magma and water created a plume of ple volcanoes, which rarely reach over 200 metres in volcanic ash and gas over 10 km high. The start of height. They are built up by many eruptions over a disruption to aviation activity occurred from this long time period, of lavas ranging from basalt to rhy- date. On Sunday 18 April it was estimated that about olite but the average composition is andesitic lava. A 750 tonnes of magma was ejected every second. By large amount of pyroclastic material is also ejected 20 April most of the ice in the crater appeared to from this type, consisting of have melted and the plume was only reaching heights of 4 Km. > Volcanic bombs or blocks (several metres to 6.4 cm) By the end of April explosive activity had virtually > Lapilli (6.4 cm to 2 mm) ended with a weak plume largely of steam, but some lava still flowed from the crater northwards for about > Volcanic ash (2mm to 0.25 mm) 2 Km. > Volcanic dust (less than 0.25 mm) Just when we thought things were returning to nor- > Pumice, vesicular glassy material mal, in early May Eyjafjallajokull started to increase > Scoria, vesicular material heavier and darker explosive activity, sending an ash plume up to 9Km than pumice. on occasions. During the first two weeks of May, the Along with the lava flows the resulting cone is com- activity became cyclical and earthquake activity posed of layers of lava alternating with pyroclastics recorded the rise of magma and gas from deep be- and can reach heights up to 2,000 metres. Typical neath the volcano. The explosive activity was now examples are Mt Fuji in Japan, Mt Mayan in the being driven by gas dissolved in the rising magma Philippines and Mt Agua in Guatemala. which expands rapidly as it nears the surface, no The history of the recent eruptions longer a water magma reaction. Around December 2009, seismic activity was de- But the explosive nature of the recent eruptions is a tected in the volcano area, with thousands of small product of the magma composition and this could earthquakes (mostly magnitude 1-2 on the Richter continue for some time, possibly easing and then magnitude scale, with only a couple greater than 3 erupting spasmodically. magnitude) 7-10 kilometres beneath the volcano. On What made this volcanic activity so disruptive to air 26 February 2010, unusual seismic activity alon with travel was the combination of the following four fac- rapid expansion of the Earths crust was registered by tors: the Meteorological Institute of Iceland. This gave 1. The volcano’s location is directly under the Jet geophysicists evidence that magma was pouring Stream. from underneath the crust into the magma chamber of the Eyjafjallajokull volcano and the pressure 2. The direction of the Jet Stream was unusually stemming from the process caused the huge crustal stable at the time of the eruption’s second phase, displacement at Porvaldseyri farm. The seismic ac- maintaining a continuous south-easterly heading. tivity continued to increase and from 3-5 March 3. The second eruptive phase took place under 2010, close to 3,000 earthquakes was measured at 200 m of glacial ice. The resulting melt water the epicentre of the volcano. flowed back into the erupting volcano which cre- The eruption is believed to have begun on 20 March ated two specific phenomena. from a fissure vent about 8 km east of the top crater a) The rapidly vaporising water significantly in- and was not under the glacier, this phase ejected creased the eruption’s explosive power. olivine, basaltic and andesite lava with little explo- b) The erupting lava cooled very rapidly which sive activity and ash only reaching a height of 4 Km. created a cloud of highly abrasive, glass-rich ash. this eruption then became subdued. 4. The volcano’s explosive power was sufficient to On 14 April 2010 Eyjafjallajokull resumed erupting, inject ash directly into the Jet Stream. this time from the top crater in the centre of the gla- Not to bother the reader too much, but the real con- pre-eruption levels. There have been no ash fall re- cern at present is the Eyjafjallajokull volcanoes near ports and low water discharge from the Gigjokull neighbour the Katla volcano some 25 km away. In a glacier. But volcanoes are very unpredictable crea- recent paper in the journal Developments in Quater- tures and renewed eruptions are possible. nary Science, a team led by University of Gothen- So if you plan on flying in the coming weeks, con- burg researcher Erik Stukell notes that the two sider the ash disruption insurance being offered by erupted together in 1612 and again from 1821 to most of the Airlines, when you book your seat. 1823. And their data indicates that Katla is capable of releasing far more material during an eruption, Compiled from a wide range of scientific and non-scien- tific sources, so that you the reader can understand the re- than Eyjafjallajokull cent events that caused such wide spread disruption to air Stop press: as of Monday May 24 2010 eruptions travel a little better have ceased, since Saturday there have been no ex- Terry Warrington plosions at the summit, and tremor has reduced to

ARTICLES AND INFORMATION FROM OTHER BRANCH NEWSLETTERS North West Branch Severnside Building Stones of Manchester University and its Why is there no Chalk in the Irish Sea; Prof John Environs, led by Norma Rothwell Cope (Cardiff University) A very interesting article which although specific to During the Cretaceous, sea levels were possibly 200 Manchester could equally apply anywhere. The gen- metres higher than present time. England, Ireland eral gist is that the older a building is then the more and Wales were all under water and so Chalk likely the stone used is local. But as transport links formed; so where has it all gone? From about 80 Ma and the wealth of towns and cities improved, so did there was uplift under NW Scotland and by the early the building stone, becoming more and more exotic Tertiary the uplift was in the area now occupied by and from distant lands. For example South Dakota, the Irish Sea forming a Dome now why is that? Norway, Egypt and more recently China “is there Speculation points to a mantle plume associated with nothing that does not come from China these days”? Atlantic rifting. Erosion was rapid, about 2 km of The rest of the article goes on to describe actual rock was lost close to the dome, accelerated by the stones found in more detail, but what this article rivers cutting through the rocks and soft chalk, evi- shows is that you do not have to live near rock expo- dence of which today is that most rivers in Ireland, sures to have an interest in Geology, just visit your England and Wales radiate around the Irish Sea. local Town Hall. When the dome subsided or the hot spot moved on the Irish Sea developed. So why is there no Chalk in the Irish Sea - well it was not there to receive it.

Having trawled through 10 Branch Newsletters what did I find, well to be honest, very little of interest to other than their own Branch Members. What they do have is a far greater quantity of field trips and talks available when compared to our own. However, this is not a good comparison since by its very name Open University Geological Society Mainland Europe covers a far greater catchment area, a bit like comparing Switzerland with Russia. I find our Newsletter equal in all respects to any other produced, but like them all we need contributions. So whether it’s about stones in your backgarden or an interesting article you have read, send it in. Correlated by your own librarian Terry Warrington. THE JURA WEEKEND: ARCHAEOLOGY AND GEOLOGY 12 -13 June 2010 / branch meeting / guests are welcome The preliminary programme: Saturday M. Leng who is an archaeologist employed by the local administration regarding conservatory work will give us a private visit of a small museum in Champagnole that displays models of the country- side and roman vestiges of a site he has been exca- vating. Then we will make our way up to the top of a local hill Mont Rivel to look at these remains. We will take time on that hill to visit a couple of quarries on the Mont Rivel that gives us an insight into Oxfordian Strata (UpperJurassic) and a place to look for some fossils. Elodie Molléon, a master stu- dent in archaeo-geology, will give us information about the quaternary around Mont Rivel. This hill is Sunday morning we will head again to the plateau an outlier and its history is linked with the last gla- above Champagnole, where we will have a look on cial periods. other geo features like karstic erosion patterns (lapiaz) and twisted strata in the Syam Faisceau (typ- After lunch some where in a sunny or shaded place ical local). Eventually we will meet Jean François as you feel like…, driving back, we will have a few Richard who discovered the Dino footprints and will stops along the plateau and the famous Reculée des tell us about it. Planches which both are specific landscape features of the western edge of the Jura. Robert Heslop who is a member of our Branch wrote an extensive article in the OUGS Journal Spring Edi- We will stop at another quarry cut into the Middle tion 2008 about these and other dinosaur footprints. Jurassic Strata, at the southern edge of the Reculée. Thereby we will have travelled through the main To finish the day, we will go back at the bottom of Jurassic strata. the reculée to visit the cave Grotte des Planches (http://www.grotte-des-planches.net) which is To finish that day we will go into the vineyards famous in Europe for its giant pots. growing on the Lias (Lower Jurassic) and Triassic. We will also taste some of it in a caveau. At the exit of the cave, excavations showed traces of occupation by people going 10,000 years back. Elodie will tell us more about this. To prepare that weekend I met Michel Campy (Pro- FOR FRENCH SPEAKERS: fessor emeritus of l'Université de Bourgogne) who "Le département de Physiolgie et de Géologie wrote in collaboration with Vincent Bichet (Maître de l'Institut Catholique de Lille" organises a de conférence [professor] at Université de Franche- week in Velay: Comté) an amazing book about the geology of the Géologie et Ecologie d'un terroir. Jura, two years ago (sorry, the book is in French…). From the 11th to the 16th of July. Anyone interested in the subjects is welcome! For more information,get in touch with Elisabeth d'Eyrames ([email protected]) PRELIMINARY PROGRAMME FOR THE POST-EXAM FIELD TRIP TO BAVARIA AND WESTERN from Sunday 24th October to Sunday 31st October Estimated cost (not including the journey to Munich, meals and drinks): 440,00 Euro

Sunday 24 October Travel to Munich, overnight stay in the YH Munich-Thalkirchen. Meet at 18:00 in YH meeting room, dinner at ca. 19:00 in “Asam Schloessl” in Munich-Thalkirchen.

Monday 25 October Depart YH 08:00 for Windischeschenbach ca. 13:00 Continental Deep Drilling Project KTB. Tour Guide Dr. Frank Holzförster, Head of the KTB Geocentre. ca. 15:30 meet with Dr. Andreas Peterek and visit the Tertiary basalt cone in Parkstein. Dinner and overnight stay “Gasthof zum Waldnaabtal” in Windischeschenbach.

Tuesday 26 October Start field trip, 08:00: The Geology of the western border zone of the Bohemian Massif (KTB surroundings, , Münchberg Nappe- Complex) (Guided by Dr. Andreas Peterek and Dr. Johann Rohrmüller) Dinner and overnight stay “Gasthof zum Waldnaabtal” in Windischeschenbach.

W’day 27 October Start field trip, 08:00: The Geology of the Teplá-Barrandium in the Mariánské Lázně region and Neotectonics along the Mariánské Lázně fault zone. (Guided by Dr. Andreas Peterek, N.N.) Dinner and overnight stay Kloster Hotel Teplá.

Thursday 28 October Start field trip 08:00: Evolution and neotectonics of the intra-continental Eger (Ohře) Rift (Guided by Dr. Andreas Peterek, N.N.) Dinner and overnight stay Kloster Hotel Teplá.

Friday 29 October Depart 08:00 for Regensburg, sight-seeing in the city centre, UNESCO World Heritage Site. Overnight stay in the YH Munich-Thalkirchen. Dinner ca. 19:00 in “Alter Wirt” in Munich-Thalkirchen.

Saturday 30 October Depart YH 09:00 for Munich Mineral and Fossil Fair (Mineralientage). Dinner ca. 19:00 “Augustiner Keller” in the City centre. Overnight stay YH Munich-Thalkirchen.

Sunday 31 October Travel home

For more information regarding the excursions planned for 26th-28th October, see the following abstracts from Dr. Andreas Peterek. The Geology of the western border zone of the Cadomian units. We will discuss the Bohemian Massif (KTB surroundings, Fichtel tectonometamorphic evolution of the Tépla-Bar- Mountains, Münchberg Nappe Complex) randium especially with respect to the adjacent Guided by Dr. Andreas Peterek (Bayreuth University Moldanubian and Saxothuringian units. We will also and Geopark Bayern-Böhmen) and Dr. Johann present results from our own studies dealing with the Rohrmüller (Landesamt für Umwelt, Geological recent tectonic activity along the prominent Marián- Survey) ské Lázně fault zone which is along its northern branch one of the source areas of the Northwest Bo- The western border zone of the Bohemian Massif is hemian swarm earthquakes. one of the best geologically investigated regions in Central Europe due to the German Continental Drilling Project (KTB). Following the N-S direction Evolution and neotectonics of the intra-continen- we will present the tectonometamorphic units of the tal Eger (Ohře) Rift North-Bavarian basement (Moldanubian Unit, Guided by Dr. Andreas Peterek (Bayreuth University Saxothuringian Unit, Münchberg Nappe Complex) and Geopark Bayern-Böhmen) and N.N. including the late-Variscan and will discuss one of the most spectacular fault zones in Central The Eger Rift with the central Eger Graben is one of Europe, the Franconican Lineament. the most prominent neotectonic structures in Central Europe. In its southwestern part, the Cheb Basin, strong evidence is given for active magmatic intru- The Geology of the Teplá-Barrandium in the sions which most probably induce seismic activity in Mariánské Lázně region and neotectonics along this region. We will discuss the evolution of the Eger the Mariánské Lázně fault zone Rift and of the Cheb Basin as it can be reconstructed Guided by Dr. Andreas Peterek (Bayreuth University from the volcano-sedimentary record as well as from and Geopark Bayern-Böhmen) and N.N. neotectonic and morphotectonic criteria. The field- trip will be completed by the visit of the world- The Teplá-Barandium belongs to the internal zone of famous spa town Karlovy Vary. the Variscides. Nevertheless, it is built up by supracrustal anchi- and non-metamorphic Palaeozoic rocks (Barrandium) that unconformably overly

SOME BACKGROUND ON THE LOCATIONS OF THE POST-EXAM FIELD TRIP If you wish to locate the geographical region where Bohemia. During a visit to discuss the trip with our we will spend most of the week, find a decent map chief guide, Dr. Andreas Peterek, I was well and of Central Europe and locate Munich. The city of truly made aware of the significance of the neotec- Regensburg lies about 125 km NNE of Munich. Re- tonic activities in this region and they will now play gensburg is the provincial capital of the Upper an equally important part of the programme as the Palatinate or Oberpfalz. The Oberpfalz is approxi- basement rocks. To quote Dr. Peterek, 'The Eger Rift mately trapeze-shaped and consists of the region Valley is one of the most striking neotectonic struc- northwards from Regensburg to the town of Mark- tures in Central Europe'. tredwitz, eastwards up to the border with the Czech The reconstruction of past continents and their con- Republic and westwards to the town of Neumarkt figurations seems to work fairly well, back to about i.d. Opf. Windischeschenbach and the KTB are 750 Ma, the Cryogenian, when the collision of East about 70 km north of Regensburg and Münchberg is , Laurentia and Amazonia resulted in the about 15 km south of Hof. Marienbad, or Mariánské formation of the Rodinia, just north Lázně, and Teplá are located in western Bohemia of the South Pole. This reconstruction is based some 45 km and 55 km, respectively, east of the mainly on palaeomagnetic data and the location of town of Marktredwitz. Grenvillian orogens. When the movement and as- When I originally started planning this trip, I con- sembly of microcontinents are involved, things be- centrated solely on the aspect of the Cadomian and come more speculative. Variscan basement rocks in the Oberpfalz and West It is generally proposed that rifted from north-verging thrusts that override Stephanian coal- Gondwana sometime between the Late Cambrian bearing foreland basins. and Early Ordovician, ca. 490 Ma ago and subse- 2) The central Saxo-Thuringian zone which was a quently drifted towards and collided with Laurentia, source of the Late Devonian to Early Carboniferous during the Caledonian collision, ca 440 Ma, to form flysch of the Rheno-Hercynian zone. A high-grade the basement rocks of much of England, Wales and gneissic core is thrust northwards over lower-grade southern Ireland. It is often assumed that Armorica, lower Palaeozoic sediments. Granites are common. consisting of a number of , also rifted from Gondwana by the Early Ordovician (488 Ma-478 3) The southern Moldanubian zone represents the in- Ma) and collided with Laurussia by the Late Devon- ternal zone of the orogen comprising high-grade ian (ca. 375 Ma), as the closed. metamorphic rocks, commonly Precambrian, and abundant (80 per cent) Late Devonian to Late Car- Recent publications now assume that this rifting of boniferous granites and migmatites. However, low- Armorica from Gondwana never occurred and that grade Lower Palaeozoic sediments occur locally. In Armorica was still part of northern Gondwana when the south of this zone structures verge southward; Pangea formed as a result of the Variscan collisions. that is, the folds are inclined or overturned in a As Pangea split up during the Late Jurassic to Late southerly direction. Further south, basement inliers Cretaceous (ca.150 Ma-85 Ma), Armorica finally or windows within the Alpine nappes and the Pyre- rifted from what is now Africa, to form the basement nees, contain Cambrian to Devonian sediments af- rocks of the much of central Europe. fected by pre-Stephanian with syn- So where does the Cadomian orogeny fit in to all and post-tectonic granites. this? There is a lot of confusion when the terms An important feature of all the Variscan zones is that Cadomia or Cadomian are used, as to what is actu- they have a basement which is typical of Gondwana ally meant. The Cadmonian orogeny is defined by and were deformed during the Pan-African Cado- McCann, T. (ed) 2008 . The Geology of Central Eu- mian orogeny (600–550 Ma). The Saxo-Thuringian rope. Volume 1: Precambrian and Paleozoic. Geolog- and Moldanubian zones also contain Ordovician ical Society London, as: faunas and glacial deposits typical of Gondwana. ‘A series of complex sedimentary, magmatic and If you have access to The Geology of Central Eu- tecto-metamorphic events that commenced during rope, edited by T. McCann and published by the Ge- the mid-Neopoterozoic (ca. 750 Ma) and extended ological Society, London, you can find much of the into the earliest Cambrian (ca. 540-530 Ma). These current information available about the geology of events occurred along the periphery of the supercon- Central Europe, although the entry regarding the tinent of Gondwana and were the last of a series of Eger Rift Valley is very modest. However, you need events which formed the crystalline basement rocks to be prepared to search through this massive work, of Europe’. containing a total of about 1,500 pages, to find the Assuming Armorica was still part of Gondwana as information relevant to the area and the era that you Pangea was formed by the collision of Laurussia and are interested in. I found Chapter 1 ‘The introduction Gondwana during the Variscan Orogeny, (Late and overview’, Chapter 2 ‘Precambrian’ and in par- Devonian to the mid-Carboniferous), three distinct ticular, Chapter 11 ‘Variscan tectonics’ to be very in- tectonic structual units or zones were formed, in fomative. what today is represented by Central Europe. These A good alternative to the The Geology of Central structural units or zones are defined in the following Europe is the paper: ‘Tectonic and Plate Tectonic website: Units at the North Gondwana Margin:Evidence from http://science.jrank.org/pages/48241/Variscan- the Central European Variscides’ by Wolfgang orogeny.html: Variscan orogeny - Fig. 1., verge, Franke (Intsitut fuer Geowissenschaften, Justus- Tectonophysics, Geological Society of America Spe- Libieg Universitaet, Giessen.) 1999 and published cial Paper. The evolving continents. by the ‘Austrian Geologischer Bundesanstalt’ in 1) A northern Rheno-Hercynian zone, of low meta- Vienna. morphic grade, with mainly Devonian sediments and (The Bundesanstalt kindly permit the reproduction a few granites. It is bounded to the north by of their publications for educational purposes, for which we wish to express our gratitude.) This publi- The continuation of the Frankonian lineament cation is much shorter than the information con- through the Moldanubian zone comprises mainly of tained in The Geology of Central Europe, but it the Bavarian Pfahl and Donaurandbruch faults. covers the main effects of the Variscan Orogeny on The northern boundary of the Bohemian Massif is the geology of Central Europe and it supplies a geo- formed by the Eger or Ohře Rift Valley, which is ap- logical map and an informative sketch or plate kine- proximately 300 km long and 50 km wide. The rift matic cartoon of the Central European Variscides, system is part of the European Cenozoic Rift Sys- from the Late Silurian to the Late Devonian, (ca. tem, together with the Rhine and Auvergne Grabens. 420 Ma-360 Ma). These are the events which were The Eger Rift evolved at the Upper Cretaceous/Ter- responsible for the formation of the three structural tiary boundary and reactivated the Variscan Saxo- tectonic units described above. These units are Thuringian/Moldanubian suture zone. The main shown assembled by the Frasnian, in the cartoon on rifting phase took place between 42-9 Ma, with the page 12, they are from left to right, or approximately graben formation and intraplate alkaline volcanism. north to south, the Rheno-Hercynian, the Saxo- The rifting process is still active today, this results in Thuringian and the Moldanubian zones. The paper CO2 emission at the surface in NW-Bohemia, the can be found on the website of the 'Austrian Geolo- source of the moffetes fields, and continued uplift in gischer Bundesanstalt' under some southern parts of the rift, accompanied by www.geologie.ac.at/filestore/download/AB0054_00 earthquake swarms. 7_A.pdf McCann et al describe the Bohemian Massif as I advise you to print pages 10, 11 and 12, and refer being the most important inlier of Cadomian and to these while you are reading the main body of the Variscan basement rocks in Central Europe. The text. The geological map on pages 10 and 11 also northern part of the massif forms a section of the shows the position of the KTB, the Münchberg Saxo-Thuringian Zone and its southern part lies in Complex, the Fichtel Mountains, the Teplá-Bar- the Moldanubian Zone, which also contains the randium unit and the Eger Graben. (Note, this docu- Teplá-Barrandium unit. During our trip, we will be ment starts with page 7! The pages numbered 10, 11 visiting sites and outcrops in both the Saxo- and 12 are the fourth, fifth and sixth pages within the Thuringian and Moldanubian western border zones document.) of the Bohemian Massif, as well as in the Eger The assembly of the Bohemian Massif together with Graben and in the Teplá-Barrandium unit. the Saxo-Thuringian and Moldanubian zones during Mike Molloy the Variscan orogeny, left the Bohemian Massif sur- rounded by major faults on all sides. On the western flank, it is bounded by the Franconian lineament, a NW trending system of deep reverse faults of late- to post-Variscan origin, which were reactivated by the Alpine Orogeny.