The 5th International Trilobite Conference in Prague, Czech Republic, 2012

The pre-conference fieldtrip to the Barradian area, southwest of Prague

 

by Kevin D. Brett

 

 Prague Trilobite Conference Cover

 

The pre-conference fieldtrip for the 5th International Trilobite Conference in Prague, Czech Republic took place in the Barrandian area southwest of Prague (between Prague and Plzeň) starting on June 26, 2012. Geologically, the 4-day long fieldtrip began in the Precambrian and ended in the Devonian. Each day we left Prague in the morning and toured the Czech countryside by bus, observing spectacular views, quaint villages, castles, and of course famous trilobite collecting locales. In my itinerary below, I mention mostly the collecting localities, although there were many other stops for stratigraphic interest and photos only. I must say that this fieldtrip was one of the best organized I have ever been on, and wish to congratulate our Czech hosts for a superb job!

 

A view of Praha along the Vltava Riversmall village in the Czech countryside

A view of Praha along the Vltava River and a typical small village in the Czech countryside.

Day 1 was in the Cambrian of the Příbram-Jince Basin, and included stops at : Medalův Mlýn, Vinice near Jince, Heydův dvůr near Rejkovice, and Ostrý Vrch Hill. The first stop was at Medalův Mlýn, which had outcrops of the Lower Cambrian Paseky Shale Member of the Holšiny-Hořice Formation. This shale has a low diversity soft-bodied fauna consisting of 3 arthropods (Kodymirus Association). These arthropods are extremely rare and of course none were found due to the short time we had at the site.

 

collecting in the Paseky Shalethe Paseky Shale

An Australian, a Russian, and a Canadian collecting in the Paseky Shale

The rest of the day we made several stops in the famous Jince Formation where many trilobites were found, several of which were complete. The first Jince Fm. locality was at Vinice near Jince where exposures of the stratotype section of the Jince Formation, middle Cambrian, occur along the Litavka River. This locality, as well as many of the others mentioned below, are protected sites and digging is prohibited. Although this is the case, many of the sites have been dug by local collectors, which provided much of the talus for us to search through on the fieldtrip. Palaeontologists in the Czech Republic are trying to work on more co-operative approaches with collectors in order to preserve valuable scientific specimens, while the collectors also get to keep their finds, but that is another story.

To get to the site, we had to walk a little over a kilometre and hike up to the localities on the side of the hill. The layers at this site were in the Paradoxides (P.) paradoxisimmus gracilis biozone and many parts of this large trilobite, and its relative Hydrocephalus carens, were found.

 

Searching for Paradoxides and other trilobites in the Jince FormationFieldtrip leaders Oldřich Fatka and Michal Mergl

Searching for Paradoxides and other trilobites in the Jince Formation. Fieldtrip leaders Oldřich Fatka and Michal Mergl

 

The next locality was at Heydův dvůr near Rejkovice, where the same formation is quarried by collectors along the side of a forest trail. This site is within the Paradoxides (Eccaparadoxides) pusillus zone. The fauna here is dominated by Ellipsocephalus and other polymerid trilobites, although none were found on this trip.

 

Collecting at Heydův dvůr Heydův dvůr near Rejkovice.  

Collecting at Heydův dvůr near Rejkovice.

The best stop of the day was on the slopes of Ostrý vrch Hill, between Rejkovice and Felbabka. This site is in the same biozone as Vinice and is a series of large pits dug by collectors in the woods. Going through their talus, many Paradoxides and Hydrocephalus partials were found. The total Jince Formation contains a high diversity fauna of trilobites (44 species), as well as echinoderms (14 spp.), crustaceans (6 spp.), and other fossil groups comprising a total of at least 170 species.

 

Collecting in the pits on Ostrý vrch HillFieldtrip leader Petr Budil  

Collecting in the pits on Ostrý vrch Hill. Fieldtrip leader Petr Budil in the white t-shirt.

After finishing up at this locality and departing on the bus for Prague, our gracious hosts provided a beer stop on a restaurant patio in a Czech village - a welcomed cold beverage on a hot, but successful day of collecting.

 

a young holaspidcephalona possible meraspid.      

Trilobites from the Jince Formation: all Paradoxides (Paradoxides) paradoxisimmus gracilis – Left to right: a young holaspid, cephalon, and a possible meraspid.

Day 2 was also in the Cambrian (this time in the Skryje- Týřovice Basin) and included stops at Týřovice, Luh near Skryje, Skryje, Buchava, and the monument to Joachim Barrande. After a Czech standoff with a truck on the narrow road, our first stop was an information stop only where Dr. Oldřich Fatka explained the Cambrian sequence of the area, from the Pre-Cambrian unconformity upwards.

 

 narrow Czech country roadsMartina Aubrechtová and Lukáš Lajbl    

Standoff with a truck on the narrow Czech country roads. Field trip leader Oldřich Fatka with student assistants Martina Aubrechtová and Lukáš Lajbl

 

Our first collecting stop was in the Buchava Fm., “Middle” Cambrian, at Týřovice. This site contains the famous Sao hirsuita baby trilobites (protaspid and meraspid stages) described by Joachim Barrande. Some meraspids and holaspids of Sao were found, along with a few agnostids. Everybody walked away happy from this site (especially my girlfriend, since she found a complete one).

 

 looking for Sao hirsuita in Týřovice

Splitting the layers very finely looking for Sao hirsuita in Týřovice

 

We then made a stop at a small roadside quarry (Orthisovy lumek) where Dr. Fatka gave a description of the local stratigraphy. This site, which is protected, shows the lower stratigraphic levels of the Buchava Formation unconformably overlying the Precambrian.

 

   Description of the stratigraphyprotected section

Description of the stratigraphy at a protected section

 

Our hosts then took us into the village of Skryje to the ‘Trilobit Restaurace and Pension’. They provided us with a traditional Czech meal and of course that famous Czech specialty – Pilsner beer! Our lunch was amazing and many of us sampled the traditional “mixed” beer (half and half light and dark Pilsner) and bought a trilobite t-shirt.

 

   The ‘Trilobit Restaurace and Pension’ in SkryjeThe ‘Trilobit Restaurace and Pension’

The ‘Trilobit Restaurace and Pension’ in Skryje, with me sampling the menu

 

After lunch we walked behind the restaurant to the Skryje museum and examined lots of complete trilobites and other fossils. Skryje really is a town dedicated to its trilobite heritage – with a trilobite hotel and restaurant, a museum, and a monument to Joachim Barrande.

 

 trilobites expositionHydrocephalus carens 

Checking out the trilobites and a Hydrocephalus carens

 

Following this, we walked over to Barrande’s monument and paid our tributes to this famous Czech trilobitologist. Joachim Barrande was originally French, but settled in Prague and wrote some of the first detailed monographs on trilobites in the world. His attention to detail and his voluminous works are still invaluable to this day. His ‘Systeme Silurien’ is the largest palaeontological work ever written! In the Czech world of palaeontology he is somewhat of a god. It was only fitting that we paid tribute to this world famous trilobitologist.

 

Oldřich Fatka beside Barrande’s Monument in SkryjeFieldtrip participants at the Barrande Monument in Skryje  

Oldřich Fatka beside Barrande’s Monument in Skryje. Fieldtrip participants at the Barrande Monument in Skryje: Front Row (sitting) left to right: Petr Budil, Oldřich Fatka, Gian Luigi Pillola, Kevin Brett, Evgeny Bushuev, Gulnara Mukhamedjarova. Back row (standing): Jan Jehlička, František Povolný, Gerardo Lopez-Mayoral, Paul Hong, Paul Hille, Joan Antoni Vela, Martina Aubrechtová, Lukáš Laibl, David Holloway, Jakub Vodička, Ilnara Mukhamedyarova, Robert Sensenstein (behind Barrande monument), Mary Hollingsworth, Euan Clarkson, Anastasiya Makarova, Stewart Hollingswoth, Tatyana Pegel, Martina Nohejlová, Benedicte van Lidth.

 

After lunch we continued onward to another famous trilobite site. This was Luh near Skryje in the Skryje and Slapnice Members of the Buchava Formation, middle Cambrian. This site has steep long talus slopes and collectors come here to dig the big Hydrocephalus. Several complete trilobites were found here including Hydrocephalus, Agraulos, and a solenopleurid.

 

slopes at Luh near Skryje. Agraulos ceticephalus  

Scouring the slopes at Luh near Skryje. A complete Agraulos ceticephalus found at the site.

 

The last stop of the day was at Buchava, the namesake of the Buchava Formation. A nice Agraulos was found here, as well as lots of Hydrocephalus partials.

 

 Gian Luigi Pillola hunting the outcrop at Buchava

Gian Luigi Pillola and me hunting the outcrop at Buchava

 

Day 3 was in the Ordovician of the Prague Basin with stops in the Dobrotivá Fm. at Ejpovice, the Zahořany Fm. at Loděnice, and the Chrustenice iron mine. The first stop was at an outcrop of the Dobrotivá Formation at a former iron mine in Epovice. Trilobites here occur in deepwater dark-grey to black shales. At least 2 complete cyclopygid trilobites were found here, as well as a harpid headshield (Eoharpes, rare at this locality). These cyclopygids have gigantic eyes, are considered pelagic, and perhaps even bioluminescent.

 

The international group at Ejpovice.   EjpovicePetr Kraft and Michal Mergl    

The international group at Ejpovice. Fieldtrip leaders Petr Kraft and Michal Mergl

 

After this we made a stop near the fields in Těškov. Here could be found the famous ‘Šárka’ (Rokycany) balls of the Ordovician Šárka Formation. Although collecting can only be done in the early spring or late fall, the hosts brought some concretions for us to split. The next 2 stops were trilobite faunas that occur mainly as partials, but are extremely important and rare faunas. These were the Řevnice quartzites of the Libeň Formation at Mýtský vrch Hill and the Mílina Formation at Olešná village. The first had rare trilobites preserved in quartzite, while the latter had a diverse, but rare, fauna preserved in chert.

 

Left: Michal Mergl in the Řevnice quartzites of the Libeň Formation at Mýtský vrch Hillexposures of the Mílina Formation at Olešná villageGulnara working hard      

Left: Michal Mergl in the Řevnice quartzites of the Libeň Formation at Mýtský vrch Hill. Center: Robert standing over the near vertical exposures of the Mílina Formation at Olešná village. Right: Gulnara working hard

 

After this, it was onwards to a roadcut in Loděnice. Here we collected in the Zahořany Formation, Upper Ordovician. Although the fauna is fairly diverse, we found mostly large Dalmanitina cephala and pygidia.

 

 Ordovician Zahořany Formation.Gulnara and the author with their finds 

Petr Budil of the Czech Survey explaining about the Ordovician Zahořany Formation. Gulnara and me with our finds

 

The last stop of the day was in the Chrustenice Mine at Lodenice. The temperature of 10 C was welcomed as most of the day we were collecting in 30-35 C. The tour included the mine guides starting up ancient equipment, us climbing ladders through narrow openings, a motorized mine cart ride, and detailed explanations of one of the oldest, deepest, and most complex oolithic ironstone mines in Europe.

 

   Chrustenice MineChrustenice Mine at Lodenice

Chrustenice Mine at Lodenice

 

For day 4, we were concerned with the Silurian and Devonian deposits of the Prague Basin. The first half of the day was in the Kopanina Fm (Silurian) at the famous Kosov Quarry at Beroun. There were several complete trilobites found here including Otarion diffractum and Diacanthaspis (Acanthalomina) minuta.

 

  

The famous Kosov Quarryhelping a buddy at Kosov Quarry.

The famous Kosov Quarry.

 

After a couple of hours in the quarry, we went onwards to climb Zlatý kůň Hill, near Koněprusy for an overview of the Devonian of the Prague Basin.

 

   Zlatý kůň HillKoneprusy quarry.

On top of Zlatý kůň Hill and a view from the hill of the Koneprusy quarry. Fieldtrip leader Petr Budil explaining the geology.

 

After this, we visited a quarry at Plešivec near Měňany to collect Devonian trilobites in the Koneprusy reef complex. Trilobites here are very well-preserved, but almost always partials. Some harpid headshields and phacopid partials were found here. The Koneprusy reef complex has the richest variety of all localities in the Devonian of the Barradian area.

 

Showing finds to Petr BudilGian Luigi Pillola and Robert hard at work.  

Showing finds to Petr Budil. Gian Luigi and Robert hard at work.

 

From here, we next visited the global stratotype section of the Silurian/Devonian boundary at Klonk near Suchomasty. The section exposes a complete fully marine sequence of alternating bituminous limestone and calcareous shale layers through the Silurian/Devonian boundary. This section is the first global stratotype of a system boundary ever selected (in 1972).

 

   The global stratotype monument Klonk

The global stratotype section monument at Klonk

 

The last stop of the day was at Černá rokle near Kosoř. This is one of the oldest quarries in the Czech Republic and is in the Lochov and Praha Formations, lower Devonian. After leading us up to the site, our hosts told us to collect for about 30 minutes and then mysteriously disappeared. When we walked back down to the trail, and surprise, surprise, here were our hosts beside a feast they had laid out along the trail. We dined on smoked salmon, smoked sausages, Hermelin cheese in oil, all sorts of pickles and condiments, and nice cold Pilsner beer. A nice treat at the end of our 4 day adventure.

 

 Examining the old quarry in KlonkTrilobite LunchTrilobite group     

Examining the old quarry, Lunch, and part of the group.

 

            After this grand finale, it was back to beautiful Praha and to attend the talks at the conference for the next few days.

 

  Church of Our Lady Before Tyn in Staroměstské náměstíBridges over the Vltava River in Prague.

Church of Our Lady Before Tyn in Staroměstské náměstí (old town square) and the bridges over the Vltava River in Prague.

 

All in all, we had wonderful weather, sunny and hot most of the time, and all participants found trilobites, many complete. There were approximately 20 participants on the trip from Russia, Canada, Spain, Australia, South Korea, Holland, Belgium, Italy, Scotland, the USA, and the Czech Republic. The hosts (Oldřich Fatka, Petr Budil, Petr Kraft, Michal Mergl, Jiří Kříž, and several students including Martina Aubrechtová, Martina Nohejlová, Jakub Vodička, and Lukáš Lajbl organized a fantastic trip that included classic localities, detailed stratigraphic and palaeontologic explanations, the finding of complete trilobites, exquisite locales for lunches, a mine tour, and of course lots of the Czech specialty – Pilsner Beer! We all made many friends and have memories to last a lifetime. For more photos from the conference, you may visit http://trilo2012.org/

 

Bohemian Glass trilobites 

Bohemian Glass trilobites

 
Acknowledgements:
            I would like to thank all of the fieldtrip organizers, leaders, and students (mentioned above) who made this fieldtrip a wonderful experience. Especially I would like to thank Olda Fatka, Petr Budil, and Michal Mergl for their assistance throughout the trip! Paul Hille provided some photographs and some extracurricular field collecting. Thanks to Nando Musmarra for converting the document and providing space on his webpage. Robert Sensenstein, Petr Budil, John Iellamo, and Paul Hille assisted in editing and provided helpful comments. My girlfriend Gulnara and daughter Ilnara made this fieldtrip even more wonderful, and their participation and interest greatly enhanced this trip. For all the participants, organizers, and assistants I did not specifically thank – Thank-you!

Kevin D. Brett ©