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28 octobre 2010 4 28 /10 /octobre /2010 22:10

Last summer we returned to Coulouma, where we wanted to visit some other spots in the neighbourhood of the ‘chemin du banc du Touring Club’. When we had passed the village of St-Jean-de-Minervois we met a sign 'routé barrée',  indicating the road was clossed. Apparently, road works were going on further on the road. As a car came from the opposite direction, we ignored to sign and continued our way to Coulouma. After a few turnings, we fell on yet another road sign, but we also ignored it, as we were now close to our objective. When we came out of the next turning, we could hardly believe our eyes. A huge bagger equipped with a big pneumatic hammer was destroying the rocks of the Cambrian outcrops along the road. 


One of the big baggers used to destroy the site.

We were horrified, but had no choice as to wait until the workers went home. We parked the car and went for a walk, looking for other fosiliferous outcrops. There were Cambrian rocks all over the territory, but we did not find any trilobite. Around 4 P.M. the activity on the road stopped. We returned to the car and pushed further. 



Rocks from point 22 and 13 were thrown in the ravine to enlarge to road, destroying the outcrops.

What we saw was shocking. They were enlarging the road and to do so they took big portions out of the hill and threw these in the ravine. By doing so, the small mountain road was changed in a big road. The famous French palaeontologist Robert Courtessole compiled a detailed log of the road section, identifying seven different points with each a different fauna. His points Coulouma 13, 22, 14 were already destroyed. More were to follow. Inspecting the remaining rocks, we could only conclude that the layers were relatively thin and that all the fossilliferous material had been thrown in the ravine.  


What remains of poit 13.

In Coulouma, a geological monument was destroyed. But why. This road is a small road in a deserted area were little traffic passes. The village of Coulouma it self has very narrow streets, and further on and near St-Jean-de-Minervois the road is also narrow. What is the use of this! This will not allow traffic to advance faster, this is just a track were you will be able to pass a truck or car that is driving slowly. To do so one of the important outcrops of the Middle Cambrium of the Montagne Noire was scarified. Why? Clearly, France has a strange way to deal with its geological monuments. 


Exploring the rocks of Coulouma 15.

As we could not find fossils in the remaining rocks, we went searching in the rocks thrown in the ravine to enlarge the road. The ones on the surface had suffered from the tracks of the baggers, but knocking open the big blocks of ‘schistes troués’ from point 15 proved to be very rewarding. We found numerous cephalons of  Ctenocephalus antiquus, Pardailhania hispida, Pardailhania multispinosa and Paradoxides rouvillei. At point 14 our finds were even more interesting, with cephalons of Calodiscus foveolatus, Badulesia granieri, Agraulos longicephalus and Paradoxides rouvillei.

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9 octobre 2009 5 09 /10 /octobre /2009 21:35

Last year our summer holiday took us to Brittany. This was the occasion for a trilobite trip to the South of Rennes. We concentrated on the Bain de Bretagne, La Dominelais and Le Grand Fougeray area. This zone is typical for the higher Llanvirn. (Ordovicum) and part of the ‘formation de Traveusot’ in the synclinorium of Martigné-Ferchaud.

French friends gave us some hints where to look, but in fact big parts of this area are fossiliverous. If you ride trough these villages, just look for small pits. Local farmers often have a private quarry where they exploit the schist’s. These are used for private roads, drainage of fields and even construction of walls. A quick look at the debris allows you to see if the schist’s contain any fossils. This is often the case and trilobites can be found relatively easy. Do not forget that you are on private ground and ask for permission, she mostly granted.

The Neseuretus tristani is very common over here. You find them mostly in nodules. Locals call these nodules often ‘cercueils’ (= coffins). The conservation is often poor and complete specimens are rare. You can also look for nodules on the fields, but then you need to be there when there aren’t any crops. In one of the quarries we found a Neseuretus of 25 cm in a nodule. In another quarry we visited, it was possible to search in the deeper parts of the formation. Here the conservation of the trilobites is much better and if you are lucky you can catch one of the big guys. We got one of 22 cm. You do not pick up these so easily, the rock is harder here, and getting the big blocks out is hard labour.

Neseuretus tristani

Among the other species we found are Colporyphe roualty and Eodalmatina destombesi destombesi. The first taxa is relatively easy to find, but for the Eodalmatina you need a lucky day.

Colporyphe roualty

Road works can also be interesting. One day we went shopping in the Super U in Bain the Bretagne. They were constructing new roads to access the shop and while my parents were filling their basket, I inspected the heaps with debris. Here also a lot of parts of trilobites were laying around, unfortunately nothing complete. Just when I was leaving, I discovered a Isabelinia glabrato. It’s slightly damaged, but I was very happy to find it.

Eodalmatina destombesi destombesi

Isabelinia glabrato
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14 juin 2009 7 14 /06 /juin /2009 12:11

I was able to lay hands on a selection of trilobites from the upper Cambrian of in Sweden. All come from an old collection. The labels that lay with the trilobites indicate they come from Ottenby/Öland.

Ottenby is a small village on the island Öland, the second largest Swedish island of Sweden. Öland is located in Baltic Sea just off the coast of Småland. The island is connected to the mainland across the Kalmar Strait through the Öland bridge.

Trilobites of Ottenby were found in beds or lenses of dark grey limestones, the so called stinkstones or orsten. Stratigraphically these sections belong to the Peltura scarabaeoides Zone. The fauna of these sediments is generally dominated by trilobites. The material contains (according to the labels) following taxa:

Peltura scarabaeoides (Wahlenberg 1821)

cranidium of 1,4 cm.


Sphaerophthalmus humilis (Phillips, 1848)

Compared with S. major S. humilis has narrower fixed cheeks. The eyes are further back in S. humilis and the eye-ridges are more oblique, the occipital and genal spines are shorter.

Cranidium of 2,2 mm long.

Sphaerophthalmus major (Lake 1913)

General features of the cranidium are very like those of S. humilis.

Cranidium of 2,5 mm long.

Sphaerophthalmus majusculus (Linnarsson 1880)

Has wider fixed cheeks than S. major, distinct eye-ridges, and a node in place of the occipital spine.

Cranidium of 5 mm.

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5 juin 2009 5 05 /06 /juin /2009 21:32


If talking about Belgian trilobites, then the area east of Tournai (Allain, Vaulx, Antoing) definitely figures among the well known and studied outcrops. Among the taxa described from this region are Piltonia (Piltonia) kuehnei, Cummingella (Cummingella) belisama belisama, Paladin (Kaskia) arduennensis, Parvidumus cernunnos and Witrtryides rosmerta.

Tournai is situated in the basin of the river Schelde/Escaut along the border with France in the Hainaut/Henegouwen province. From the geological point of view, the region is based on carboniferous limestone. It’s part of the eastern Synclinorium of Namur, belonging to the lower Carboniferous – Ivorian - period ( 359 to 345 million years). The so called “ Calcaire de Tournai” can be divided into two formations. The Tournai Formation is the lower and rather rich part; the Antoing Formation is situated above and not very fossiliferous. Both formations are divided into members. The famous trilobites come from the Allain, Providence, Pont-à-Rieu and Vaulx members of the Tournai Formation and from the lower part of the Calonne member of the Antoing Formation.
The Carrière du Milieu in Gaurain-Ramecroix

The carboniferous limestone is covered with meso-cenzoic formations and so one need to visit quarries and abandoned quarries to collect samples. During the 19th century numerous quarries were opened for building material. Today, remain several carries that exploit the black or grey limestone: the C.C.B SA, and the Carrière du Milieu at Gaurain-Ramecroix; the Carrière Lemay at Vaulx and the Carrières d’Antoing S.A. at Antoing. Unfortunately the quarry owners have recently become very restrictive and so it ‘s getting harder and harder to get access to the quarries. The abandoned quarries are not really an option. Most of them are inundated and have become rather dangerous. Access is often prohibited.

The Cimescaut SA quarry

We were able to visit the Cimescaut SA quarry in Antoing with our friends from the C.M.P.B. This is certainly not the richest quarry if you are looking for trilobites. Parts of trilobites are easy to find, but complete specimens are very hard to discover. Among our findings were an enrolled Piltonia kuehnei and a plate literally covered with pygidia of the same species. Some months later we could search in the Carrière du Milieu in Gaurain-Ramecroix. This is a huge quarry where trilobites are hard to catch.

Identifying trilobites from the “ Calcaire de Tournai” can be tricky, especially when dealing with damaged or only partial exoskeletons. The articles ‘Die Trilobiten des belgischen Kohlenkalkes’ by G. and R Hahn and C. Brauckmann in Geologica et Palaeontologica and the excellent volume by G. Daumeries ‘ Atlas de détermination des Trilobites Carbonifères de la Belgique’ can be a great help. The Daumeries book can be obtained through the ‘Cercle  Géologique du Hainaut’.

With Guy Daumeries in the Carrière du Milieu.


More trilobites from the Carboniferous of Tournai can be found in the album.

Tournai Tournai

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28 mai 2009 4 28 /05 /mai /2009 20:46


One of my father's favourite outcrop is the so called 'Mur des Douanniers'

in Vireux-Molhain (Ardennes - France). If you follow the D.47 from Vireux-Molhain to Treignes, you can not miss this famous spot, it's just before crossing the border into Belgium. Since 1991, the site is has become a natural reserve where fossil collecting is strictly prohibited. The penalty for illegal collecting is high, and the French police seem often present in the neighbourhood. Information panels give an overview of the taxa that were found here. Most of the names given are not correct. According to these panels the site belongs to the St. Joseph Formation. Recent research by V. Dumoulin and S. Blockmans assigns the outcrop to the Membre du Vieux Moulin, a new nember of the Jemelle Formation (Eifelian age), which fits better with the presence of the trilobites Geesops and Septimopeltis.

My father visited the site as a youngster and found the two phacopines that occur here, Geesops sparsinodosus gallicus Struve, 1982 and Pedinopariops sp. A lot of material was collected before the closure and so trilobites of Vireux are often offered for sale. We were able to buy some additional species like Gerastos catervus (van Viersen, 2006a), Cyphaspis n. sp. (van Viersen, 2006a) and nice Asteropyginae gen. & sp. indet. on fossil shows. Last year we found nice partly enrolled Cornuproetus sp. on a temporary outcrop not far from the famous 'Mur des Douanniers'. The rare ones (Lichids and Odontopleurids) on the contrary are very hard to get.

One can understand the French authorities closed the site; some fossil hunters were using heavy equipment and did a lot of damage. However the situation of the outcrop today is far from ideal. There is no physical protection (roof or so) and nature, especially erosion continues to do its work. The cliff is partly overgrown and its top layer is completely disintegrated; all fossils it contained are lost forever. There was no or poor research on trilobites from Vireux-Molhain, and it's only recently that van Viersen started a nomenclatural revision of the trilobites from this Early Eifelian Fossil-Lagerstätte. To do so he has to base on the many specimens collected by amateurs before closure and preserved in private collections and museums. A limited and temporary re-sampling at the outcrop would certainly allow a more thorough research.

The situation of the 'Mur des douanniers' in Vireux-Molhain clearly proves that any fossil collected even by an amateur, is a fossil saved; there where fossils remaining in the rock are often lost for research.


Vireux Vireux

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21 mai 2009 4 21 /05 /mai /2009 10:53


The Montagne Noire is a mountain range in southwestern France. It is located at the south-western end of the Massif Central in the border area of the Tarn, Hérault and Aude departments. Its highest point is the Pic de Nore at 1,210 m.


Since the 19th century trilobites make the paleontological celebrity of the Montagne Noire. One can find trilobites in every stratigraphic level, from the Cambrien to the lower Carboniferous. Certain levels of Cambrien, and especially of the lower Ordovician are famous. In this last stage, there are sometimes locally accumulations of phosphated nodules, and each one can contain a trilobite; the famous “schistes à gâteau”.


There are numerous fossils sites in the Montagne Noire. To visit them all, one probably needs a lifetime. We only made a short trip and could only visit a couple of sites.


Minerve is one of the 'most beautiful villages of France'. It’s a fortified medieval village, on top of the gorge carved by the River Cesse. In 1210, a group of Cathars, under attack in the Albigensian crusade, found refuge in the heavily fortified village. It took six weeks of siege, but eventually the village surrendered. The 140 Cathars were burned at the stake.


Nowadays is a lovely and attractive place. The landscape around the city is stunning and the gorges are the perfect hiding place for trilobites.

For more pictures, just open the album.




Our next stop was the small village of Vélieux. Outside this place lays another middle Cambrian fossil site, where trilobites can be found. We had little time to search, but still found some nice fragments of Eccaparadoxides brachyrachys, Conocoryphe brevifrons and Bailiella seguieri, all from the lower Languedocien, Zone à Solenopleuropsis.  


For more pictures see the album below.

Vélieux Vélieux


Coulouma is a small town in the Mounts of Pardailhan to the SE of Saint-Pons. This little village is well know for it’s fossils and gave it’s name to the ‘formation de Coulouma’. The locality is built on white limestone of the base of the middle Cambrian; around the “schistes à Paradoxides” are dominating. The fossils there abound and are often in a great state of conservation.

If Ferrals was the theatre of the first Cambrian discoveries, it is especially in Coulouma that was worked out between 1893 and 1948 the complete stratigraphy of the series of the Cambrian and the Ordovician. This was mainly the work of Miquel (1893 - 1912) and of Thoral (1925 -1935).

For a visit on the spot, the best study is once more that of Abbée Courtesolle (Le Cambrien moyen de la Montagne Noire) which describes not less than 23 fossiliferous layers. Our time being limited we decided to concentrate on the famous track of the “banc du Touring Club” and fossiliferous points 14 and 16.

At point 14 one finds the oldest fauna of the corner. The rock consist of sandy shales, white and brown, without limestone nodules, but presenting small cavities filled with limonite clay. Certain plates are constellated with small pyrite iron cubes. The layer is hardly 1 meter thick and not easy to find. If you do, one discovers there rather quickly some cephalons of Baduleisia granieri (Thoral) and Pardailhania hispida.

At point 16 the schists are green with limestone nodules; they are found in broad plates and thin beds. This 5 meter thick layer is literally full of parts of trilobites. Occasionally a complete specimen is found.

Searching for trilobites.

The path of the Bench of Touring Club crosses all the levels of middle Cambrian. Along this track Courtesolle describes six interesting spots (Coulouma 3, 4, 5, 7, 8 and 9). We inspected the open grounds just in front of the breech. The place is covered with debris and one has to search for a spot were the rock is still surfacing. We were not very successful and our findings were somewhat disappointing.

Me at work near the Banc du Touring.

A strange visitor at Coulouma 18, praying mantis inspecting Gyrocystis barrandei.


This locality is well known for it’s fossils since the publications by Bergeron (1888), Thoral (1935) and Courtesolle (1973). Ferrals offers a succession of the almost complete Lower and Middle Cambrian with an abundant presence of trilobites.

One of the important outcrops of the ‘Coulouma formation’ is located on the road to Authèze in the hamlet  “Causse”, close to a small quarry. This spot is one of the two hypostratotypes and offers a variety of fossils (trilobites, brachiopods and echinoderms). The layers have been dated to the middle Cambrian, from the lower Caesaraugustien to the Languedocien.
This formation is composed of green pelites, locally purplished, containing intercalations of carbonated nodules.


Bailiella levyi Munier-Chalmas and Bergeron, 1889

Among the trilobites described from this outcrop are varieties of: Eccaparadoxides, Solenopleuropsis, Conocoryphe, Bailiella, Ctenocephalus, Pardailhania, Velieuxia, Agraulos, Badulesia, Calodiscus, Pseudoperonopsis, Phalagnostus, Galagnostus, Condylopyge, Phalacroma, …

Cranidium of Conocoryphe brevifrons

Ctenocephalus begeroni

More images can be found in the album.

Ferrals-les-Montagnes Ferrals-les-Montagnes



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21 mai 2009 4 21 /05 /mai /2009 10:33

Hi visitors,


I’m 15 years and I love fossils. I’m a lucky person, I managed to pass the bug to my father and so I have a chauffeur and a companion to go fossil hunting. At first, we collected all kind of fossils, but for some time now, we concentrate on our favourite fossils, the trilobites.


On these pages you will be able to follow our travels and findings. Do not hesitate to comment and correct our mistakes.



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