Bellier, Jean-Pierre

Kuhnt, Wolfgang

Moullade, Michel

Renard, Maurice

Tronchetti, Guy

Carnets de géologie (Notebooks on geology)

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Carnets de Géologie / Notebooks on Geology - Letter 2004/02 (CG2003_A02_MM_etal)
1
The Gargasian (Middle Aptian) of Cassis-La Bédoule 
(Lower Aptian historical stratotype, SE France): 
geographic location and lithostratigraphic correlations
Michel MOULLADE1
Guy TRONCHETTI2
Wolfgang KUHNT3
Maurice RENARD4
Jean-Pierre BELLIER5
Key Words: Stratigraphy; Cretaceous; Aptian; Gargasian; Bedoulian; stratotype; France
Citation: MOULLADE M., TRONCHETTI G., KUHNT W., RENARD M., BELLIER J.-P. (2004).- The Gargasian
(Middle Aptian) of Cassis-La Bédoule (Lower Aptian historical stratotype, SE France): geographic
location and lithostratigraphic correlations.- Carnets de Géologie / Notebooks on Geology, Maintenon,
Letter 2004/02 (CG2004_L02_MM_etal)
Mots-Clefs : Stratigraphie ; Crétacé ; Aptien ; Gargasien ; Bédoulien ; stratotype ; France
                                                
1 Centre de Recherches Micropaléontologiques, Museum d'Histoire Naturelle, 60 Bd Risso, 06000 Nice
(France); Centre de Sédimentologie-Paléontologie, CNRS UMR 6019, Université de Provence, Centre St Charles,
Case 67, Pl. Victor Hugo, 13331 Marseille Cedex 03 (France)
Michel.Moullade@unice.fr
2 Centre de Sédimentologie-Paléontologie, CNRS UMR 6019, Université de Provence, Centre St Charles, Case
67, Place Victor Hugo, 13331 Marseille Cedex 03 (France)
3 Institut und Museum für Geologie und Paläontologie, Christian-Albrechts-Universität, Olshausenstraße 40, D-
24118 Kiel (Germany)
4 Département de Géologie Sédimentaire et CNRS FR32, Case 116, Université Pierre et Marie Curie, 4 Place
Jussieu, 75252 Paris Cedex 05 (France)
5 Département de Géologie sédimentaire et CNRS FR32, Case 104, Université Pierre et Marie Curie, 4 Place
Jussieu, 75252 Paris Cedex 05 (France)
Manuscript online since March 21, 2004
In the middle of the last century
Gargasian strata overlying the historical
stratotypic beds of the lower substage of
the Aptian (Bedoulian) were still well
exposed in a number of quarries that
extended in a NNE-SSW trending belt from
the village of Roquefort-la Bédoule to the
vicinity of the Cassis railway station (Fig.
1).
In the La Bédoule region these quarries
first supplied the nearby lime kilns
abandoned early in the 19th century, and
then the Lafarge cement plant near the
Cassis railway station. By the middle of the
2 0th century their exploitation had stopped
completely and the plant had shut down.
The lack of replacement act ivity,
urbanization and the beginning of some
rehabilitation has had a deleterious effect,
so that in our day only the large and
southwesternmost quarry called "La
Marcouline" (Fig. 2) allows us to
investigate an almost continuous section of
Gargasian strata about 70 m thick, of which
the upper twenty meters are being rapidly
degraded.
T h e  f o l l o w i n g  biostratigraphic
investigation shows that the lower fifty
meters, still in a state that permits detailed
sampling, include only the lower Gargasian
and the lower part of the middle Gargasian.
The remainder of the series is represented
by a broad brush-covered tract where some
scattered outcrops of sandy marls of upper
Gargasian and possibly Albian age were
still visible in the sixties. Furthermore,
blocks of talus from the cliff of Cenomanian
limestones that caps the succession are
scattered profusely on the brush-covered
slope. The top of that resistant limestone
forms a line of crests that are a prominent
element of the topography from Cassis in
the SSW to the Pas d'Ouillier in the NNE.
Although the two are almost in direct
prolongation, it is impossible to correlate
precisely the base of the Gargasian
sequence in the La Marcouline quarry with
that of the Bedoulian of the historical
stratotype that was restudied in detail in
1998 (MOULLADE, TRONCHETTI & MASSE). The
Carnets de Géologie / Notebooks on Geology - Letter 2004/02 (CG2003_A02_MM_etal) 
2 
uppermost beds of the Bedoulian (sensu CONTE, 
1994) crop out (less and less, alas) at the top of 
the Comte quarry, just below the D1 
departmental road from Cassis to Roquefort-La 
Bédoule. They are separated from the 
Gargasian at La Marcouline by a covered zone, 
formed in part by the existence of the paved 
road at this place, but more substantially by the 
fact that the lowermost beds of the Gargasian, 
less resistant than beds of the Bedoulian below 
and the later Gargasian above, have flowed like 
mud and formed colluvium easily invaded by 
vegetation. So now these passage beds crop out 
almost nowhere in the entire area.  
 
Figure 1: Map of the Cassis - Roquefort-La 
Bédoule area. C = Comte quarry; M = La Marcouline 
quarry; T = Les Tocchis section.  
 
Figure 2: Map of the area near the Cassis railway 
station. C = Comte quarry; M = La Marcouline 
quarry.  
The situation was different in the sixties, at 
least in the vicinity of La Bédoule, in a tract, 
now a development, "Les Tocchis", 2 km ENE of 
the La Marcouline quarry. At this site a simple 
piecemeal survey resulted in the recording of 
about 15 meters of an uninterrupted sequence 
beginning at the limestone of Bedoulian bed 170 
(in the nomenclature used by MOULLADE et alii, 
1998) and ending in a triplet of limestone beds 
in the basal Gargasian sequence, numbered 
196, 197 and 198, slightly thicker and thus more 
conspicuous topographically than the remainder 
of the section (Fig. 3). The outcrops of this 15 m 
succession, more marly than the overlying and 
underlying beds, are today completely 
inaccessible because of urbanization. But in 
1963 one of us mapped and sampled it in detail 
(M.M.). We are now able to link the uppermost 
beds of the Comte quarry with the lowermost at 
La Marcouline only with the help of this Les 
Tocchis section and in particular the samples 
collected then (Fig. 3).  
 
Figure 3: Lithostratigraphic correlation of the 
Bedoulian-Gargasian transition using the Comte 
quarry (C), Les Tocchis (T) and La Marcouline quarry 
(M) sections as successive relays.  
A direct lithostratigraphic correlation 
between the Les Tocchis section and the 
presumably equivalent sequence at La 
Marcouline is rather difficult. The outcrops at Les 
Tocchis were both eroded and weathered. So 
harder beds there were conspicuous, whereas at 
La Marcouline the beds are in a steep, recently-
worked face so differences in the weathering 
profiles of hard and soft beds is less 
pronounced. In addition, the thicknesses of 
some beds seem to be different in the two sites. 
Figure 4: Gargasian section at La Marcouline 
quarry. !! 

Carnets de Géologie / Notebooks on Geology - Letter 2004/02 (CG2003_A02_MM_etal) 
4 
As mentioned, in the Les Tocchis section the 
196-197-198 limestone beds made up a hard 
triplet marker, clearly defined and forming a 
relief. At La Marcouline the basal succession has 
at least three triplets: beds 2-4-6; beds 10-12-
14; beds 22-24-26, all of them more or less 
alike and geometrically capable of representing 
the triplet at Les Tocchis. As it turned out, the 
last was slightly more prominent than the other 
two (Fig. 3). 
 
Figure 5: Variation in the CaCO3 content of the 
marly (dots) and limy (squares) Gargasian beds in 
the La Marcouline quarry section.  
Consequently, it was necessary to use 
biostratigraphy to calibrate these three groups 
with more accuracy and thus to arrive at a 
precise correlation of the Les Tocchis triplet 196-
197-198 with beds 22-24-26 at La Marcouline 
(Fig. 3) 
In fact the double micropaleontologic datum 
based on the simultaneity of the first 
appearance of the planktonic foraminifer 
Globigerinelloides ferreolensis (MOULLADE) and 
the disappearance of Schackoina (Leupoldina) 
cabri SIGAL occurs at La Marcouline 3.5 m below 
the base of bed 22, the lowermost of the triplet 
22-24-26 (MOULLADE et alii, this volume). At Les 
Tocchis, the sampling of that time was a little 
less closely spaced. Nevertheless this datum 
was found 3.3 m under bed 196, the lowest of 
the 196-197-198 triplet. The foraminiferal 
correlation is supported by the distribution of 
the calcareous nannofossils (BERGEN et alii, this 
volume).  
The equivalent of marker bed 170 near the 
base of the Les Tocchis section is also clearly 
recognizable in the Cassis sequence (Comte 
quarry). So, using Tocchis as an intermediate 
point, it was possible to calibrate the La 
Marcouline section to the Bedoulian stratotype 
(Fig. 3)  
At first glance the Gargasian sequence 
cropping out at Marcouline (Fig. 4) is 
distinguished by its marked rhythmicity caused 
by a fairly regular alternation of "limestones" 
and "marls". Calcimetric analyses (RENARD et 
alii, this volume) show that the well-marked 
difference in weathering pattern has only a 
slight relationship with the composition of the 
strata: calcium content (CaCO3) ranges from 53 
per cent in the most marly interbeds to 87.5 per 
cent in the most limy levels. The entire 
sequence can be split into several second order 
cycles that are differentiated mainly by changes 
in the amount of divergence between the 
limiting percentages (Fig. 5). We shall not 
discuss here the details of these analyses and 
the possible significance of the cyclicity. These 
topics are developed in full elsewhere in this 
volume (RENARD et alii; KUHNT & MOULLADE) and 
in addition will be compared (see the final 
chapter of syntheses in this volume) with the 
findings of the micropaleontologic analyses in 
order to refine paleoenvironmental and 
paleoclimatic interpretations. 
Acknowledgements 
The authors wish to express their gratitude 
to Nestor J. SANDER for his assistance in the 
translation of the French version of this paper, 
to Jean CHAROLLAIS for a critical review of the 
manuscript, and to the Lafarge cement 
company for allowing and facilitating our access 
to the La Marcouline quarry. 
References 
CONTE G. (1994).- La limite Bédoulien-
Gargasien dans la coupe stratotypique de 
Cassis-La Bédoule (Bouches-du-Rhône, 
France).- Géologie Alpine, Grenoble, Mém. 
H.S., N° 20, p. 321-326.  
MOULLADE M., TRONCHETTI G. & MASSE J.-P. 
(eds.) (1998).- Le stratotype historique de 
l'Aptien inférieur (Bédoulien) dans la région de 
Cassis-La Bédoule (S.E. France).- Géologie 
Méditerranéenne, Marseille, t. XXV, Nº 3-4, 298 
p.  
MOULLADE M., TRONCHETTI G., BUSNARDO R. & 
MASSE J.-P. (1998).- Description lithologique des 
coupes-types du stratotype historique de 
l'Aptien inférieur dans la région de Cassis-La 
Bédoule (SE France).- Géologie 
Méditerranéenne, Marseille, t. XXV, N° 3-4, p. 
15-29.  


The Gargasian (Middle Aptian) of Cassis-La Bédoule (Lower Aptian historical stratotype, SE France):geographic location and lithostratigraphic correlations

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The Gargasian (Middle Aptian) of Cassis-La Be´doule(Lower Aptian historical stratotype, SE France):geographic location and lithostratigraphic correlationsMichel Moullade, Guy Tronchetti, Wolfgang Kuhnt, Maurice Renard,Jean-Pierre BellierTo cite this version:Michel Moullade, Guy Tronchetti, Wolfgang Kuhnt, Maurice Renard, Jean-Pierre Bellier.The Gargasian (Middle Aptian) of Cassis-La Be´doule (Lower Aptian historical stratotype, SEFrance): geographic location and lithostratigraphic correlations. Carnets de Geologie, Carnetsde Geologie, 2004, CG2004 (L02-en), pp.1-4. <hal-00142249>HAL Id: hal-00142249https://hal.archives-ouvertes.fr/hal-00142249Submitted on 18 Apr 2007HAL is a multi-disciplinary open accessarchive for the deposit and dissemination of sci-entific research documents, whether they are pub-lished or not. The documents may come fromteaching and research institutions in France orabroad, or from public or private research centers.L’archive ouverte pluridisciplinaire HAL, estdestine´e au de´poˆt et a` la diffusion de documentsscientifiques de niveau recherche, publie´s ou non,e´manant des e´tablissements d’enseignement et derecherche franc¸ais ou e´trangers, des laboratoirespublics ou prive´s.Carnets de Géologie / Notebooks on Geology - Letter 2004/02 (CG2003_A02_MM_etal)1The Gargasian (Middle Aptian) of Cassis-La Bédoule (Lower Aptian historical stratotype, SE France): geographic location and lithostratigraphic correlationsMichel MOULLADE1Guy TRONCHETTI2Wolfgang KUHNT3Maurice RENARD4Jean-Pierre BELLIER5Key Words: Stratigraphy; Cretaceous; Aptian; Gargasian; Bedoulian; stratotype; FranceCitation: MOULLADE M., TRONCHETTI G., KUHNT W., RENARD M., BELLIER J.-P. (2004).- The Gargasian(Middle Aptian) of Cassis-La Bédoule (Lower Aptian historical stratotype, SE France): geographiclocation and lithostratigraphic correlations.- Carnets de Géologie / Notebooks on Geology, Maintenon,Letter 2004/02 (CG2004_L02_MM_etal)Mots-Clefs : Stratigraphie ; Crétacé ; Aptien ; Gargasien ; Bédoulien ; stratotype ; France                                                1 Centre de Recherches Micropaléontologiques, Museum d'Histoire Naturelle, 60 Bd Risso, 06000 Nice(France); Centre de Sédimentologie-Paléontologie, CNRS UMR 6019, Université de Provence, Centre St Charles,Case 67, Pl. Victor Hugo, 13331 Marseille Cedex 03 (France)Michel.Moullade@unice.fr2 Centre de Sédimentologie-Paléontologie, CNRS UMR 6019, Université de Provence, Centre St Charles, Case67, Place Victor Hugo, 13331 Marseille Cedex 03 (France)3 Institut und Museum für Geologie und Paläontologie, Christian-Albrechts-Universität, Olshausenstraße 40, D-24118 Kiel (Germany)4 Département de Géologie Sédimentaire et CNRS FR32, Case 116, Université Pierre et Marie Curie, 4 PlaceJussieu, 75252 Paris Cedex 05 (France)5 Département de Géologie sédimentaire et CNRS FR32, Case 104, Université Pierre et Marie Curie, 4 PlaceJussieu, 75252 Paris Cedex 05 (France)Manuscript online since March 21, 2004In the middle of the last centuryGargasian strata overlying the historicalstratotypic beds of the lower substage ofthe Aptian (Bedoulian) were still wellexposed in a number of quarries thatextended in a NNE-SSW trending belt fromthe village of Roquefort-la Bédoule to thevicinity of the Cassis railway station (Fig.1).In the La Bédoule region these quarriesfirst supplied the nearby lime kilnsabandoned early in the 19th century, andthen the Lafarge cement plant near theCassis railway station. By the middle of the2 0th century their exploitation had stoppedcompletely and the plant had shut down.The lack of replacement act ivity,urbanization and the beginning of somerehabilitation has had a deleterious effect,so that in our day only the large andsouthwesternmost quarry called "LaMarcouline" (Fig. 2) allows us toinvestigate an almost continuous section ofGargasian strata about 70 m thick, of whichthe upper twenty meters are being rapidlydegraded.T h e  f o l l o w i n g  biostratigraphicinvestigation shows that the lower fiftymeters, still in a state that permits detailedsampling, include only the lower Gargasianand the lower part of the middle Gargasian.The remainder of the series is representedby a broad brush-covered tract where somescattered outcrops of sandy marls of upperGargasian and possibly Albian age werestill visible in the sixties. Furthermore,blocks of talus from the cliff of Cenomanianlimestones that caps the succession arescattered profusely on the brush-coveredslope. The top of that resistant limestoneforms a line of crests that are a prominentelement of the topography from Cassis inthe SSW to the Pas d'Ouillier in the NNE.Although the two are almost in directprolongation, it is impossible to correlateprecisely the base of the Gargasiansequence in the La Marcouline quarry withthat of the Bedoulian of the historicalstratotype that was restudied in detail in1998 (MOULLADE, TRONCHETTI & MASSE). TheCarnets de Géologie / Notebooks on Geology - Letter 2004/02 (CG2003_A02_MM_etal) 2 uppermost beds of the Bedoulian (sensu CONTE, 1994) crop out (less and less, alas) at the top of the Comte quarry, just below the D1 departmental road from Cassis to Roquefort-La Bédoule. They are separated from the Gargasian at La Marcouline by a covered zone, formed in part by the existence of the paved road at this place, but more substantially by the fact that the lowermost beds of the Gargasian, less resistant than beds of the Bedoulian below and the later Gargasian above, have flowed like mud and formed colluvium easily invaded by vegetation. So now these passage beds crop out almost nowhere in the entire area.   Figure 1: Map of the Cassis - Roquefort-La Bédoule area. C = Comte quarry; M = La Marcouline quarry; T = Les Tocchis section.   Figure 2: Map of the area near the Cassis railway station. C = Comte quarry; M = La Marcouline quarry.  The situation was different in the sixties, at least in the vicinity of La Bédoule, in a tract, now a development, "Les Tocchis", 2 km ENE of the La Marcouline quarry. At this site a simple piecemeal survey resulted in the recording of about 15 meters of an uninterrupted sequence beginning at the limestone of Bedoulian bed 170 (in the nomenclature used by MOULLADE et alii, 1998) and ending in a triplet of limestone beds in the basal Gargasian sequence, numbered 196, 197 and 198, slightly thicker and thus more conspicuous topographically than the remainder of the section (Fig. 3). The outcrops of this 15 m succession, more marly than the overlying and underlying beds, are today completely inaccessible because of urbanization. But in 1963 one of us mapped and sampled it in detail (M.M.). We are now able to link the uppermost beds of the Comte quarry with the lowermost at La Marcouline only with the help of this Les Tocchis section and in particular the samples collected then (Fig. 3).   Figure 3: Lithostratigraphic correlation of the Bedoulian-Gargasian transition using the Comte quarry (C), Les Tocchis (T) and La Marcouline quarry (M) sections as successive relays.  A direct lithostratigraphic correlation between the Les Tocchis section and the presumably equivalent sequence at La Marcouline is rather difficult. The outcrops at Les Tocchis were both eroded and weathered. So harder beds there were conspicuous, whereas at La Marcouline the beds are in a steep, recently-worked face so differences in the weathering profiles of hard and soft beds is less pronounced. In addition, the thicknesses of some beds seem to be different in the two sites. Figure 4: Gargasian section at La Marcouline quarry. !! Carnets de Géologie / Notebooks on Geology - Letter 2004/02 (CG2003_A02_MM_etal) 4 As mentioned, in the Les Tocchis section the 196-197-198 limestone beds made up a hard triplet marker, clearly defined and forming a relief. At La Marcouline the basal succession has at least three triplets: beds 2-4-6; beds 10-12-14; beds 22-24-26, all of them more or less alike and geometrically capable of representing the triplet at Les Tocchis. As it turned out, the last was slightly more prominent than the other two (Fig. 3).  Figure 5: Variation in the CaCO3 content of the marly (dots) and limy (squares) Gargasian beds in the La Marcouline quarry section.  Consequently, it was necessary to use biostratigraphy to calibrate these three groups with more accuracy and thus to arrive at a precise correlation of the Les Tocchis triplet 196-197-198 with beds 22-24-26 at La Marcouline (Fig. 3) In fact the double micropaleontologic datum based on the simultaneity of the first appearance of the planktonic foraminifer Globigerinelloides ferreolensis (MOULLADE) and the disappearance of Schackoina (Leupoldina) cabri SIGAL occurs at La Marcouline 3.5 m below the base of bed 22, the lowermost of the triplet 22-24-26 (MOULLADE et alii, this volume). At Les Tocchis, the sampling of that time was a little less closely spaced. Nevertheless this datum was found 3.3 m under bed 196, the lowest of the 196-197-198 triplet. The foraminiferal correlation is supported by the distribution of the calcareous nannofossils (BERGEN et alii, this volume).  The equivalent of marker bed 170 near the base of the Les Tocchis section is also clearly recognizable in the Cassis sequence (Comte quarry). So, using Tocchis as an intermediate point, it was possible to calibrate the La Marcouline section to the Bedoulian stratotype (Fig. 3)  At first glance the Gargasian sequence cropping out at Marcouline (Fig. 4) is distinguished by its marked rhythmicity caused by a fairly regular alternation of "limestones" and "marls". Calcimetric analyses (RENARD et alii, this volume) show that the well-marked difference in weathering pattern has only a slight relationship with the composition of the strata: calcium content (CaCO3) ranges from 53 per cent in the most marly interbeds to 87.5 per cent in the most limy levels. The entire sequence can be split into several second order cycles that are differentiated mainly by changes in the amount of divergence between the limiting percentages (Fig. 5). We shall not discuss here the details of these analyses and the possible significance of the cyclicity. These topics are developed in full elsewhere in this volume (RENARD et alii; KUHNT & MOULLADE) and in addition will be compared (see the final chapter of syntheses in this volume) with the findings of the micropaleontologic analyses in order to refine paleoenvironmental and paleoclimatic interpretations. Acknowledgements The authors wish to express their gratitude to Nestor J. SANDER for his assistance in the translation of the French version of this paper, to Jean CHAROLLAIS for a critical review of the manuscript, and to the Lafarge cement company for allowing and facilitating our access to the La Marcouline quarry. References CONTE G. (1994).- La limite Bédoulien-Gargasien dans la coupe stratotypique de Cassis-La Bédoule (Bouches-du-Rhône, France).- Géologie Alpine, Grenoble, Mém. H.S., N° 20, p. 321-326.  MOULLADE M., TRONCHETTI G. & MASSE J.-P. (eds.) (1998).- Le stratotype historique de l'Aptien inférieur (Bédoulien) dans la région de Cassis-La Bédoule (S.E. France).- Géologie Méditerranéenne, Marseille, t. XXV, Nº 3-4, 298 p.  MOULLADE M., TRONCHETTI G., BUSNARDO R. & MASSE J.-P. (1998).- Description lithologique des coupes-types du stratotype historique de l'Aptien inférieur dans la région de Cassis-La Bédoule (SE France).- Géologie Méditerranéenne, Marseille, t. XXV, N° 3-4, p. 15-29.  

The Gargasian (Middle Aptian) of Cassis-La Bédoule (Lower Aptian historical stratotype, SE France): geographic location and lithostratigraphic correlations

The Gargasian (Middle Aptian) of Cassis-La Bédoule (Lower Aptian historical stratotype, SE France):geographic location and lithostratigraphic correlations

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