A preliminary quantitative study of Foraminifera within the paleoenvironmental record of the Aptian stratotypes

A

naaabr©

K

R

saafllée©

M

1

cT

0d

Revue de micropaléontologie 53 (2010) 193–208

Original article

A preliminary quantitative study of Foraminifera within thepaleoenvironmental record of the Aptian stratotypes

Étude quantitative préliminaire des Foraminifères dans lecontexte paléoenvironnemental de l’Aptien stratotypique

Michel Moullade a,∗,b, Guy Tronchetti b

a Centre de recherches micropaléontologiques, Muséum d’histoire naturelle de Nice, 60, boulevard Risso, 06300 Nice, Franceb EA 4234, centre de sédimentologie et paléontologie, laboratoire de géologie des systèmes et des réservoirs carbonatés,

université de Provence, campus Saint-Charles, case 67, place Victor-Hugo, 13331 Marseille cedex 3, France

bstract

In an attempt to decipher the biotic response of Foraminifera to the paleoenvironmental changes recorded in the Aptian historical stratotypes, aumber of quantitative parameters (i.e. specific diversity and abundance of dominant groups) were examined in three sections of upper Bedouliannd lower Gargasian beds in south-eastern France. In most cases, the established biotic changes do not correlate strictly with obvious lithologicalnd geochemical variations such as the percentage of CaCO3 and �13C. However, a pattern of cyclic fluctuations in various microfaunal parametersppears to exist in parts of the studied interval, which may record paleoenvironmental changes due to a cyclic orbital forcing. To test this hypothesis,ased on a preliminary study, a more closely spaced sampling of these continuous, expanded and relatively well calibrated stratotypic series isequired.

2010 Elsevier Masson SAS. All rights reserved.

eywords: Benthic foraminifera; Aptian; Historical stratotypes; Paleoenvironments; Paleobiodiversity; Quantitative micropaleontological methods

ésumé

Plusieurs paramètres quantitatifs, tels que la diversité spécifique et l’abondance des groupes dominants, ont été examinés dans le Bédoulienupérieur et le Gargasien inférieur de Cassis-La Bédoule et de La Tuilière-Saint-Saturnin-lès-Apt afin d’élucider la réponse des foraminifèresux changements du paléoenvironnement dans les stratotypes historiques de l’Aptien. Le plus souvent, les changements affectant la microfaunepparaissent assez décorrélés des évidentes variations lithologiques et géochimiques telles que le pourcentage de CaCO3 et �13C. Cependant, des
uctuations cycliques des différents paramètres microfauniques qui apparaissent dans certaines parties de l’intervalle étudié pourraient constituer
’enregistrement de changements du paléoenvironnement dus à un forcage cyclique de type orbital. Afin de tester cette hypothèse, résultant d’unetude encore préliminaire, il faudra recourir à une maille d’échantillonnage beaucoup plus dense dans ces séries stratotypiques, continues, dilatéest relativement bien calibrées sur le plan biostratigraphique.

2010 Elsevier Masson SAS. Tous droits réservés.

nviro

cs

ots clés : Foraminifères benthiques ; Aptien ; Stratotypes historiques ; Paléoe

. Introduction

Quantitative studies related to the environmental signifi-ance of living benthic foraminifera are relatively numerous.hese methods have been transposed without major diffi-

∗ Corresponding author.E-mail address: [email protected] (M. Moullade).

PpA11M1

035-1598/$ – see front matter © 2010 Elsevier Masson SAS. All rights reserved.oi:10.1016/j.revmic.2010.01.001

nnements ; Paléobiodiversité ; Méthodes micropaléontologiques quantitatives

ulties to the Quaternary, and even to the Neogene. Thesetudies are little less numerous for the Late Cretaceous-aleogene. The Early Cretaceous was primarily the object ofioneering work focused mainly on the Tethyan realm (paleo-tlantic, southeastern France) (e.g., Dupont, 1980; Guérin,
981; Darmedru, 1982; Moullade, 1984; Kuhnt and Moullade,991; Magniez-Jannin, 1992; Coccioni and Galeotti, 1993;agniez-Jannin and Dommergues, 1994; Erbacher et al., 1998,
999; Holbourn and Kuhnt, 2001; Holbourn et al., 2001;

dx.doi.org/10.1016/j.revmic.2010.01.001

mailto:[email protected]

dx.doi.org/10.1016/j.revmic.2010.01.001

1 e micropaléontologie 53 (2010) 193–208

D(

vtqowi12iitc

oofLtA

doc(amaw

••

2

swal

Atsss1smifiti

Fig. 1. Location of the Bedoulian and Gargasian stratotypes.C

BbaaGpTodf(

94 M. Moullade, G. Tronchetti / Revue d

auphin, 2002, etc. . .), and more rarely on the Boreal realmMichael, 1968).

Concerning the use of microfaunas to study the paleoen-ironments of the Aptian stratotypes, one can only mentionhe qualitative approach of Tronchetti (1981) and the semi-uantitative study of Moullade et al. (1998), within the framef primarily paleontological and biostratigraphic work. Recentork using the methods of integrated stratigraphy significantly

mproved knowledge of the Aptian stratotypes (Kuhnt et al.,998; Moullade et al., 1998, 2005, 2008; Ropolo et al., 2006,008; Babinot et al., 2007; Baudin et al., 2008). Consequently,t seemed of interest to use a quantitative approach to exam-ne fluctuations in the distribution of benthic foraminifera inhose localities where the biochronologic framework is wellontrolled.

Here, we present the results of a preliminary analysis, basedn three examples, of variations in the quantitative parametersf upper Bedoulian and lower Gargasian benthic and planktonicoraminifera. The stratotype sections involved are from Cassis-a Bédoule (Bouches-du-Rhône, southeastern France) and from

he area of Apt (sector of La Tuilière, near Saint-Saturnin-lès-pt, Vaucluse, southeastern France) (Fig. 1).Both Aptian stratotype series were deposited in moderately

eep intrashelf basins (Masse et al., 1998). In contrast to manyther areas of the world, these rocks display a detailed andontinuous record of the main geological events of this periodGranier et al., 2008). The benthic microfaunas have an over-ll similarity in composition from one basin to another and areoderately abundant and generally well-diversified. These char-

cteristics led us to carry out more focused and detailed tests,hich deal respectively with:

the upper Bedoulian of Cassis-La Bédoule;the Gargasian (pro parte: Praehedbergella luterbacheri andGlobigerinelloides ferreolensis zones) of Cassis and of LaTuilière.

. Paleoenvironmental setting of the Aptian stratotypes

The information on the paleoenvironment of the Aptiantratotypes is essentially available in the micropaleontologicalorks of Tronchetti (1981) for the Aptian of Basse-Provence

nd of Moullade et al. (1998) for the Bedoulian type-ocality.

The initial benchmark for the paleobathymetry of the lowerptian at Cassis-La Bédoule is the very shallow deposits of

he uppermost Barremian represented by the Urgonian lime-tone facies with neritic faunas (e.g., Rudists, Orbitolinids). Thisector of the type-area then recorded the effects of a progres-ive drowning during the Barremo-Bedoulian transition (Masse,998), as a consequence of the widespread Aptian transgres-ion on European platforms. The concomitant evolution of theicrofaunal composition during the lower part of the Bedoulian

s shown by the progressive appearance of increasingly diversi-ed planktonic foraminifera and in the simultaneous reduction,

hen the disappearance, of littoral benthic forms. These datandicate a progressive increase of water depth during the early

Blia

arte de localisation des stratotypes du Bédoulien et du Gargasien.

edoulian, with a culmination in the early Gargasian. Theenthic stock is dominated by genera with agglutinating testsnd calcareous cement such as Tritaxia and Falsogaudryinella,nd by genera with hyaline tests such as Lenticulina andavelinella. Benthic foraminifera remained an important com-onent compared with the proportion of planktonic forms.hese assemblages of outer platform type contrast with thosef the deep Vocontian basin, where planktonic foraminiferaominate (always ≥ 90%), benthic assemblages are sensibly dif-erent and in particular devoid of Tritaxia and FalsogaudryinellaMoullade, 1966). These observations indicate that from lateedoulian to early-middle Gargasian times, the water depth, at

east greater than a few tens of meters, hardly exceeded 100 mn the Cassis-La Bédoule basin. The late Bedoulian appear-nce of more diversified planktonic foraminifera, including

e mic

g(as

BocalaaoftifomnwsA

3

3

3

ctt(UClobM

3

FC

M. Moullade, G. Tronchetti / Revue d

enera and species with elongate chambers such as SchackoinaLeupoldina) and Pseudoschackoina, shows that this moder-tely deep distal basin had good connections with the openea.

Overall, the Aptian foraminiferal microfaunas of the Aptasin are not significantly different from those of the Aptianf Basse-Provence; there are, however, some minor discrepan-ies between the two assemblages. In the Apt sector, planktonicsre fewer, of smaller size and those with elongate chambers areess often present. Some benthic genera or species that occurt Cassis (e.g., Falsogaudryinella moesiana, Spiroplectinatand Globorotalites) are rare or even absent at Apt. Indicatorsf shallower paleodepths such as ornate ostracodes, relativelyew at Cassis, are more numerous. It should be also notedhat because drowning of the platform began later here thann Basse-Provence (Masse, 1976), the very shallow Urgonianacies persisted longer in the Vaucluse, attaining the lower partf the Bedoulian. On the basis of significant differences inicrofaunal composition, we may also assume that the commu-

ications of the Apt basin with the nearby Vocontian Troughere not easy. These characteristics suggest that depths were

lightly less and connection with the open sea more restricted inpt than at Cassis.

ttsp

ig. 2. Location of the studied sections in the Cassis-La-Bédoule area.arte de localisation des coupes du secteur de Cassis-La-Bédoule.

ropaléontologie 53 (2010) 193–208 195

. The studied sections

.1. The upper Bedoulian of Cassis-La Bédoule

.1.1. Location and lithologyThe Lower Aptian stratotype series is still more or less

ompletely visible in a continuous section that extends fromhe Villeneuve Quarry/Cassis-La Bédoule railway station to theop of the Comte Quarry (Fig. 2). The “La Bédoule Formation”Moullade et al., 1998) conformably overlies Barremian beds ofrgonian facies. This Formation is divided in three Members:alcareous, Marly-calcareous and Marly (op cit.) (Fig. 3). A

ithological discontinuity in the form of a subtle hardgroundccurs at the top of calcareous bed 128 and marks the boundaryetween the Calcareous Member and the Marly-calcareousember.

.1.2. Age controlAmmonite distribution, in particular that of the represen-

atives of the family Deshayesitidae, constitutes the principalool used to define the biogeochronology of the Bedoulian sub-tage in its type-area (Ropolo et al., 1998, 2006). The upperart of the Calcareous Member is assigned to the Weissi Zone

196 M. Moullade, G. Tronchetti / Revue de mic

Fig. 3. Composite section of the Cassis-La-Bédoule area.Coupe composite du secteur de Cassis-La-Bédoule.

aTZlal

actps

•

•

•

ropaléontologie 53 (2010) 193–208

nd constitutes the upper part of the lower Bedoulian (Fig. 4).he Marly-calcareous Member corresponds to the Deshayesione and constitutes the thickest part of the upper Bedou-

ian. Finally, the basal few meters of the Marly Member,ttributed to the Furcata Zone, represent the uppermost Bedou-ian.

Some reservations have been expressed by Moreno etl. (2007) about the identification of certain Deshayesitidaeollected in Cassis-La Bédoule by Ropolo et al. (1998). Addi-ional biogeochronologic calibration can be defined using otherroxies such as micropaleontological datums or geochemicalignatures:

the datum defined by the first occurrence of the plank-tonic foraminifer Schackoina cabri is interesting because thisspecies with radially elongated chambers is easy to identifyand is universally used in Tethyan biostratigraphy. How-ever, its level of appearance is often poorly calibrated. Inthe stratotype section, this cabri datum has been found atthe level of bed 145 (Moullade et al., 1998), thus permit-ting a division of the Deshayesi Zone into two nearly equalparts;the principal elements of dating provided by calcareous nan-nofossils (Bergen, 1998) are as follows:◦ first occurrence of Hayesites irregularis at the level of

bed 60, which corresponds to the Barremian/Aptian bound-ary; this limit is not involved in this study,

◦ last occurrence of Conusphaera mexicana (bed 114),◦ first occurrence of Rhagodiscus angustus (bed 129),◦ first occurrence of Eprolithus floralis, the marker which

defines the zonal limit NC6/NC7, at the level ofbed 169,

◦ the “Nannoconid Crisis” event (e.g., Erba, 1993; Herrle andMutterlose, 2003) is difficult to discern in the stratotype.Bergen (1998) saw three distinct episodes of decrease ordecline of nannoconids in the Cassis section, separated byepisodes of recovery. The most marked episode of declinefalls in an interval from beds 134 to 146 and may representthe world-wide nannoconid crisis (Erba et al., 1999) gen-erally seen as only one event. That single event recognizedelsewhere may be the consequence of slower rates of sed-imentation or even hiatuses, whereas in the expanded andcontinuous stratotype section details of the variations arerecorded more fully;

the curve of the �13C variations in Cassis, compiled here(Fig. 4) from Kuhnt et al. (1998), is roughly similar torecords obtained in many localities of the world (Weissertand Bréhéret, 1991; Weissert and Lini, 1991; Jenkyns, 1995;Vahrenkamp, 1996; Erbacher and Thurow, 1997; Menegattiet al., 1998; Herrle et al., 2004; Heldt et al., 2008; Li et al.,2008; Mutterlose et al., 2009). However, the curve from Cas-
sis is a little atypical in detail, so that the exact delimitation ofisotopic “stages” as defined by Menegatti et al. (1998) is notalways easy. A tentative interpretation in terms of Menegattiet al.’s stages, including the OAE1a event (from bed 136 to158) is presented in Fig. 4.

M.M

oullade,G.Tronchetti/R

evuede

micropaléontologie

53(2010)

193–208197

Fig. 4. Upper Bedoulian quantitative data from Cassis-La-Bédoule. CaCO3 content compiled from Masse and Machhour (1998) and from Renard and de Rafelis (1998), �13C values from Kuhnt et al. (1998). NB:niveau blanc; BS: black shales; d: discontinuity; C2 to C8: �13C isotopic subdivisions (nomenclature of Menegatti et al., 1998).Données quantitatives du Bédoulien supérieur de Cassis-La-Bédoule. Teneurs en Ca3CO compilées de Masse et Machhour (1998) et de Renard et de Rafelis (1998), valeurs de �13C d’après Kuhnt et al. (1998).NB : niveau blanc ; BS : marnes sombres ; d : discontinuité ; C2 à C8 : subdivisions de la courbe isotopique du �13C (nomenclature de Menegatti et al., 1998).

198 M. Moullade, G. Tronchetti / Revue de micropaléontologie 53 (2010) 193–208

Fig. 5. La Marcouline Quarry section.Coupe de la carrière de La Marcouline.

M. Moullade, G. Tronchetti / Revue de micropaléontologie 53 (2010) 193–208 199

FC

3

3

dubod(rc00i

3

bfs3sB

t6otGi

3

3

s(ea(tLLt

ig. 6. Location of the sector of Apt-Gargas-La Tuilière.arte du secteur d’Apt-Gargas-La Tuilière.

.2. The Gargasian of Cassis

.2.1. Location and lithologyAt Cassis and at La Bédoule, the 5 to 10 m thick pre-

ominantly marly layers which form the transition from theppermost Bedoulian to the basal Gargasian are now covered,ut most of the lower Gargasian and the middle Gargasian croput in quasi-continuity to a thickness of about 50 m in an aban-oned quarry known as La Marcouline (Moullade et al., 2004)Figs. 2 and 5). Here the succession is represented by a veryegularly rhythmic alternation of calcareous beds and marly-alcareous interbeds, the thickness of which can vary from.20/0.30 to 0.50/0.60 m for the limestones and from 0.40 to.60/0.70 m, sometimes a little more, for the marly calcareousnterbeds.

.2.2. Age controlRecently, dating of the Gargasian series at La Marcouline has

een improved using the stratigraphic distribution of planktonicoraminifera (Moullade et al., 2005) and of ammonites of the
ubfamily Cheloniceratinae (Ropolo et al., 2008). The lower3 m of the section are ascribed to the Martini ammonite zone,ubdivided in three subzones (successively Debile, Gracile anduxtorfi), and the uppermost part of the section is attributed
Ta

e

o the Melchioris zone. On the basis of foraminifera, the basal.5 m of La Marcouline section correspond to the upper partf the Praehedbergella luterbacheri zone, the following 13.5 mo the Globigerinelloides ferreolensis zone, the next 20 m to thelobigerinelloides barri zone and the upper 5 m to the Globiger-

nelloides algerianus zone.

.3. The Gargasian of La Tuilière

.3.1. Location and lithologyThe uppermost Bedoulian and the lower Gargasian can be

een in continuity by combining a series of overlapping sectionsPichouraz, La Tuilière W, Les Gays, Fig. 6; see also Moulladet al., 2006) located on either side of the hamlet of La Tuilière,distant (of 5 km) part of the village of Saint-Saturnin-lès-Apt

Vaucluse). Located only a few kilometers from Apt and Gargas,he historical Aptian and Gargasian type-localities, this sector ofa Tuilière can be considered as part of the stratotype area. Thea Tuilière composite section is continuous and preserves the

ransition from the Bedoulian to the Gargasian in great detail.
his was never the case at Gargas, even when outcrops were stillccessible.
The Aptian series at La Tuilière (Fig. 7) consists almostntirely of bluish to blue-yellowish marls, with the exception of

200 M. Moullade, G. Tronchetti / Revue de mic

FC

tk

•

•

3

aeficB

sBaCaS

eatoTsVlmTs

buabcpcao

4

es

ig. 7. Section of the sector of La Tuilière.oupe du secteur de La Tuilière.

wo levels, which constitute the only lithologically identifiableey beds within this very homogeneous marl:

a thin more calcareous bed, which is quite visible at the baseof the uppermost Bedoulian of the Pichouraz section; thisbed may represent the top of a small subunit of several thin
more calcareous layers interbedded within the marls (Dutour,2005). This subunit might be a homologue of the “WhiteLevel” defined in the Bedoulian of the Vocontian Basin (Friès,1987; Bréhéret, 1997; Dauphin, 2002);
aidu


a sequence of 10 meters of marls rhythmically interbeddedwith centimetric yellowish marly calcareous layers a littlemore hardened than the enclosing bluish marl. Because it isin a stratigraphic position similar to that of the volcanogenicepisode in the Vocontian lower Gargasian called the “VanGogh” level (Dauphin, 2002), we (Moullade et al., 2006) hadtentatively correlated these yellowish layers in the upper lowerGargasian (Globigerinelloides ferreolensis zone) of La Tuil-ière with that event. However, we are unable to support thisattribution using petrographic and/or geochemical data.

.3.2. Age controlAt La Tuilière, even though based on rich populations of

mmonites (Dutour, 2005), interpretation of the macrofaunallements for dating the Bedoulian/Gargasian transition is dif-cult. It is thus necessary to call upon microfaunas to makeonsistent comparisons with the sections of the Cassis-Laédoule area.

The base of the Pichouraz section contains the ammonitepecies Dufrenoyia furcata, which is the index of the uppermostedoulian zone. Its presence makes the lithologic correlationbove mentioned with the “White Level” equivocal, since atassis-La Bédoule and in the Vocontian realm, this level is dateds being in the underlying upper but not uppermost Grandisubzone.

In addition, at La Tuilière the range of the genus Dufrenoyiaxtends upward into the Gargasian series, an extension not seent Cassis-La Bédoule (Conte, 1994; Ropolo et al., 2008), nor inhe Vocontian realm (Dauphin, 2002). But at Cassis, the homol-gous basal Gargasian beds are more condensed than at Lauilière, and their outcrops were sparse even in the past andince then the urbanization has made them inaccessible. In theocontian Basin, these levels are extremely condensed, even

acunary (hiatus). And, according to Dutour (2005), the upper-ost specimens of Dufrenoyia from the lower Gargasian at Lauilière are not the Bedoulian index-species furcata but otherpecies (praedufrenoyi, dufrenoyi).

Because it is difficult to identify the Bedoulian-Gargasianoundary in the stratotypes using ammonite biostratigraphy, wesed a triple micropaleontological datum proxy (Moullade etl., 2006), which is based on the simultaneous extinction of aenthic foraminifer (Lenticulina cf. nodosa), an ornate ostra-ode (Protocythere bedoulensis) and the first occurrence of alanktonic foraminifer (Praehedbergella luterbacheri). In theurrent state of our research, this triple datum appears to coincidelmost exactly with the boundary determined by the extinctionf Dufrenoyia furcata.

. Methods

The samples used for this preliminary study came from sev-ral sources and were not originally processed for statisticaltudies of foraminifers (see Moullade et al., 1998, 2005). So we
ttempted to compensate for their heterogeneity by preservingnsofar as possible a certain consistency among the quantitativeata, although unable to apply the strict protocol defined andsed by Guérin (1981) for Mesozoic material.

e mic

tfFca

ald

netrfbFG

5

5

5

itmA2

tugn(Ttc

fcC

iic1v

fsf

•

•

•

5

1tmOtcsmtotttTtbtd

staOdvtstf


The moderate faunal density of the Aptian material led uso a quasi exhaustive picking of benthics from the > 63 �mraction of each sample using the same grid-plate (built byema-Salzgitter). This procedure makes it possible to refer theollected and counted microfauna to a given number of squares,nd thus compare the actual quantity of the various samples.

The microfaunas from the Aptian type localities are moder-tely well preserved overall; preservation is better in the marlyevels than in the calcareous ones, without obvious signs ofissolution in either.

The disparity of origin does not hinder reckoning withoutotable bias the number of planktonic and benthic species inach sample. Therefore, the main aim of our investigation washe study of specific diversity. We also took into account theelative abundance of agglutinated and hyaline benthic forms;or a more detailed analysis we used the numerically dominantenthic groups (cf. Plate 1) at the generic level, such as Tritaxia,alsogaudryinella, Praedorothia, Lenticulina, Gavelinella, andloborotalites.

. Quantitative analysis of foraminifera

.1. The upper Bedoulian of Cassis-La Bédoule

.1.1. DataThis study of quantitative micropaleontology deals primar-

ly with the uppermost part of the Calcareous Member andhe Marly-calcareous Member, using the lithostratigraphic ter-

inology defined by Moullade et al. (1998) for the Lowerptian stratotype series (Cassis section). Counts were made on2 samples from bed 121 to 173b.

The data obtained are graphically presented in a comparativeable (Fig. 4) juxtaposing the curves of CaCO3 content, �13C val-es, number of planktonic and benthic species of foraminifera,lobal abundance of benthic foraminifera and of aggluti-ated foraminifera, and the abundance of some benthic generaagglutinated: Tritaxia, Falsogaudryinella, Praedorothia andextulariopsis; hyaline: Lenticulina, Gavelinella and Globoro-alites) selected because they constitute the most representativeomponents of the microfauna.

Overall variations in the diversity and abundance oforaminifera are all in phase, whereas there appears no clearorrelation between the foraminiferal trends and variations inaCO3 content and �13C values.

The lower part of the foraminiferal curves (levels 121 to 147)s not very significant because sampling was too widely spacedn this part of the section. Nevertheless, this part of the sequenceomprises the highest (level 129) and the lowest (levels 136 and39) values of benthic abundance, and the lowest (level 139)alue of benthic diversity.

The most remarkable sequence is in the set of samplesrom bed 151 to 161. This interval includes three well-delimitedhort and successive episodes of variations in the quantitative
oraminiferal parameters:
marked increase (which culminates in 152a and 153a) suc-ceeding a long period of generally low values. A maximum

1Oca


of planktonic diversity coincides there with a strong globalbenthic abundance and with high values for most of the gen-era. It should be noted that this “recovery” at the end of theOAE1a event is concomitant with the fall of carbonate content(values hitherto equal to or most often higher than 80% aresucceeded abruptly by values of 75% or less), together witha positive shift (at least 2‰) of �13C;marked simultaneous decrease of foraminiferal abundanceand diversity from bed 153b to 159. This clear and brutal sig-nificant fall of biodiversity and abundance of all foraminiferais the most prominent of all such phenomena within thesection, but is not accompanied by a significant variationin CaCO3 content and �13C. In comparison with enclosingbeds, there is just a very slight increase of the organic mattercontent (TOC values – moreover quite low in the absolute –about 0.2/0.3% vs ≤0.1%, according to Masse and Machhour,1998);short and clear period of “recovery” in diversity and abun-dance from bed 159 to 161 that culminates in 159a. There areno changes in the geochemical parameters of these levels.

.1.2. InterpretationThe foraminiferal crisis recorded between samples 153b to

59, already described by Moullade et al. (1998) and thenhought to be unique, was regarded as an indication that this level

ight be an expression of the global oceanic anoxic sub-eventAE1a (Selli Event). This assumption was supported by the fact

hat this predominantly marly level, even though providing TOContents not significantly higher than in the remainder of the sub-tage, ended with a few meters of softer blackish shales. Thisore comprehensive study shows that the crisis, which affected

he foraminifers at this level, was in fact preceded by severalthers that were scarcely less intensive. These crises occur inhe interval between C3 to the lowermost part of C7 carbon iso-ope excursions of Menegatti et al. (1998), reinterpreted here onhe basis of the �13C curve published by Kuhnt et al. (1998).his reinterpretation correlates the main microfaunal crisis of

he 153b–159 interspace with an interval including most of car-on isotope stages C5 and C6 and the lowermost part of C7,hat is to say with the end of the OAE1a sub-event as recentlyelimited by Li et al. (2008).

Some authors (e.g., Erbacher et al., 1998) infer that a cri-is corresponding to an anoxic event (the OAE1b sub-event inhis case) appears to have directly influenced the distributionnd composition of benthic foraminifera in the Vocontian Basin.ur results for the OAE1a at the Cassis-La Bédoule stratotypeo not corroborate this point. In this area, faunal compositionaries only slightly during this period, and quantitative varia-ions reflect only a general cyclic trend which affect the entireeries in a regular fashion. At that time in the Aptian strato-ypes, the paleoenvironment was never anoxic or even hypoxic,or their content of TOC was very low (Masse and Machhour,
998; Baudin et al., 2008). It is only during the last phases ofAE1a (153b–159) that a tenuous hypoxic trend can be asso-iated with a faunal crisis slightly more marked than the othersnd which ends in dark shales.


Plate 1. 1–3: Tritaxia pyramidata Reuss, 1863. Les Gays section; 1, 2: sample 2328; 3: sample 2336; 4–6, 12: Praedorothia sp. gr. hechti-subtrochus. Pichourazsection; 4, 5: sample 2286; 6, 12: sample 2292; 7–9: Falsogaudryinella moesiana (Neagu, 1965). Les Gays section, sample 2336. 10, 11: Falsogaudryinella tealbyensis(Bartenstein, 1956). La Tuilière section, sample 2352; 13–16: Lenticulina cf. nodosa (Reuss, 1863). Pichouraz section 13, 14: sample 2288; 15, 16: sample 2293.17, 20, 21; Gavelinella sp. gr. flandrini Moullade, 1960. 17: Pichouraz section, sample 2359; 20: La Tuilière section, sample 2354; 21: Pichouraz section, sample2359. 18, 19: Gavelinella sp. aff. flandrini Moullade, 1960. La Tuilière section, sample 2368.

e mic

dCoLMIsaFrsscc

5

5

clff2

tvlT

s2crc

p(i(to“ipd

sa

ou

doahlb

5

(aigitnef�wfc

hsbcnumeonc

5

5

atGm

1dF1d2


This regular alternation of periods of marked increase andecrease of the biological parameters in the upper Bedoulian ofassis-La Bédoule (Fig. 4) is similar to cyclicity in other epochsf the Cretaceous reported by several authors (cf. Michael, 1968;eary et al., 1989; Coccioni and Galeotti, 1993; Tyszka, 2009).ost interpreted these fluctuations as being of orbital origin.

n the Lower Aptian stratotype confirmation of this hypothe-is would require much denser and more continuous samplings well as an even more precise biochronological framework.or this purpose, the upper Bedoulian of the type-locality wasecently drilled with a ∼100% core recovery. This unbrokenequence will allow very dense sampling so the signature andignificance of the cyclicity described in this preliminary studyan be better investigated and its cause identified more pre-isely.

.2. The Gargasian of Cassis

.2.1. DataOur study deals with the lower 21 m of the La Mar-

ouline Quarry section, which includes the Praehedbergellauterbacheri (pro parte) and Globigerinelloides ferreolensisoraminiferal zones. Counts were made on 17 samples takenrom bed M1 to M39 (numbering according to Moullade et al.,004).

The data obtained are presented graphically as a compara-ive table (Fig. 8), juxtaposing curves of CaCO3 content, �13Calues, number of planktonic and benthic agglutinated and hya-ine species of foraminifera, and the abundance of the generaritaxia, Falsogaudryinella, and Lenticulina.

The CaCO3 and �13C curves were obtained from a very denseampling (generally one every 0.50 m; Kuhnt and Moullade,007; Renard et al., 2007). These curves are generally inverselyorrelated. Both show a very clear cyclicity, which accuratelyeflects that of the lithostratigraphy (regular alternation of cal-areous and marly calcareous deposits).

The amplitude between the “calcareous pole” and the “marlyole” is better marked in the lower 13 m of the sectionCaCO3 values > 85% for limestones vs 55% for the more marlynterbeds) and culminates in three more massive calcareous bedsM22, M24, M26) which constitute a characteristic “triplet” inhe section (Fig. 5). In the upper 8 m of the section the contentf carbonate varies less (75–80% for limestones vs 60–70% formarly” interbeds). The pattern of CaCO3 values thus makest possible to divide the interval into a more calcareous lowerart and a more marly upper part; the boundary between these
ivisions is the top of the above mentioned “triplet”.
The �13C data also make it possible to divide the sequencetudied into two parts, but the boundary (a marked negative shiftt 10 m) is at the base, not at the top of the triplet. The �13C values

Bbt4

–3 : Tritaxia pyramidata Reuss, 1863. Coupe des Gays ; 1, 2 : échantillon 2328 ;e Pichouraz ; 4, 5 : échantillon 2286 ; 6, 12 : échantillon 2292. 7–9 : Falsogaudryalsogaudryinella tealbyensis (Bartenstein, 1956). Coupe de La Tuilière, échantillon4 : échantillon 2288 ; 15, 16 : échantillon 2293. 17, 20, 21 : Gavelinella sp. gr. flande La Tuilière, échantillon 2354 ; 21. Coupe de Pichouraz, échantillon 2359. 18, 19 : G368.


f the lower part range between 3.3 and 4.3‰. The values of thepper one range between 2.6 and 3.6‰.

The fluctuations of the biological parameters are less clearlyefined. The lower 2 m reflect more or less confusedly the firstrder lithologic cyclicity but the remainder shows no correlationt all. On the other hand, the curve of the diversity of benthicyaline species has clear cyclic fluctuations, of which the wave-ength is about 4 to 5 m; such fluctuations are less clearly definedy the other biological parameters.

.2.2. InterpretationTaking into account the pioneering works of Cotillon et al.

1980) and Cotillon and Rio (1984) in the Vocontian Basin,nd by using spectral analysis, Kuhnt and Moullade (2007)nterpreted the regular, small scale pattern in the lithologic andeochemical parameters (wavelength approximately 1 m) seenn the Gargasian of Cassis as an expression of a Milankovitch-ype cyclicity (precessional cycles). The fact that this cyclicity isot present in the biological curves may have been the result ofither or both of two factors: one because sampling for micro-ossils was not as closely spaced as that used for CaCO3 and13C. The other is that, except in the first two meters, countsere made only on samples from softer marly beds. Values of

oraminiferal diversity and abundance are lower in the morealcareous strata.

According to Kuhnt and Moullade (2007), in addition to theseigh frequency cycles, the stratonomy of La Marcouline sectionhows low frequency cycles (varying from 15 to 20 m) that maye interpreted as the expression of the 400 ky long eccentricityycles. As the interval studied here is short (21 m), this trend can-ot be detected in fluctuations of the biological parameters. Butsing Kuhnt and Moullade’s estimates, a wavelength of 4–5 mentioned above corresponds chronologically to 100 ky short

ccentricity cycles, which may be like that of the fluctuationsf the benthic hyaline species curve. This working hypothesiseeds to be tested with a more appropriate sampling and stricterounting procedures.

.3. The Gargasian of La Tuilière

.3.1. DataOur study deals with a composite section of ∼60 m which

ssociates the upper part of the marls of the Pichouraz section,he La Tuilière s.s. section and the major part of the marls of Lesays section (Figs. 6 and 7). The series thus includes the upper-ost part of the Schackoina cabri zone, that is to say the topmost
edoulian, all of the Praehedbergella luterbacheri zone, and thease of the Globigerinelloides ferreolensis zone, i.e., it includeshe major part of the lower Gargasian. Counts were made on4 relatively closely spaced samples (from one to two every
3 : échantillon 2336. 4–6, 12 : Praedorothia sp. gr. hechti-subtrochus. Coupeinella moesiana (Neagu, 1965). Coupe des Gays, échantillon 2336. 10, 11 :2352. 13–16 : Lenticulina cf. nodosa (Reuss, 1863). Coupe de Pichouraz ; 13,rini Moullade, 1960 ; 17 : Coupe de Pichouraz, échantillon 2359 ; 20 : Coupeavelinella sp. aff. flandrini Moullade, 1960. Coupe de La Tuilière, échantillon

204M

.Moullade,G

.Tronchetti/Revue

dem

icropaléontologie53

(2010)193–208

Fig. 8. Lower Gargasian quantitative data from La Marcouline. CaCO3 content compiled from Renard et al., 2007, �13C values from Kuhnt and Moullade (2007).Données quantitatives du Gargasien inférieur de La Marcouline. Teneurs en CaCO3 compilées de Renard et al., 2007, valeurs de �13C d’après Kuhnt and Moullade (2007).

e mic

mtsL

ctonpo(cpo

tsMotu

(SGvl(tdtct2

5

potclGg(cnnsafsbtts

crbLcC

6

lmse

•

•

tqistopbir

egvfccco

caAt


eters). Such a spacing implies a greater density of informa-ion than that obtained elsewhere for this is a very expandederies: the Praehedbergella luterbacheri zone is 50 m thick ata Tuilière instead of ∼10 m at Cassis.

We do not have yet geochemical data for this section and wean currently provide only incomplete micropaleontologic data;hese are related to the foraminiferal species diversity: numberf planktonic species, number of agglutinated benthic species,umber of hyaline benthic species. Curves of abundance of theredominant benthic species could not be constructed, becausenly semi-quantitative data were available for this parametercf. Figs 4-7 in Moullade et al., 2008). Nevertheless, diversityurves were prepared for this preliminary report (Fig. 9), as theyrovide a more significant pattern for this parameter than thosef the Gargasian of Cassis-La Marcouline.

La Tuilière curves show a more or less rhythmic alterna-ion of drops and peaks of diversity. When compared to theemi-quantitative data on foraminiferal abundance (Figs. 4–7 in

oullade et al., 2008), it appears that the declines and recoveriesf diversity coincide exactly with the variations of abundance ofhe corresponding populations; the same pattern was seen in thepper Bedoulian of Cassis-La Bédoule (see above).

Foraminiferal diversity clearly has two culminations≥ 55 species), one at the base of the section (end of thechackoina cabri zone) and the other at its top (base of thelobigerinelloides ferreolensis zone). Conversely, the inter-al between them, which corresponds to the Praehedbergellauterbacheri zone, houses the most marked crises of diversityminimum ± 10 species) and peaks lower (±40 species) thanhose of the bracketing zones. The lowermost values for theiversity and abundance are in the interval between 12 and 23 m,hat is samples 2309 to 2314 (Fig. 9). This maximal crisis coin-ides lithologically with the sequence thought to be equivalento the Vocontian “Van Gogh Level” by Moullade et al., 2006,008.

.3.2. InterpretationThe foraminiferal crisis in the interval bounded by sam-

les 2309 to 2314 of the lower Gargasian of La Tuilière is butne of an alternating sequence of similar events. This 2309o 2314 crisis is slightly more marked than the others andorresponds exactly to one of the two easily discernible litho-ogic changes (uppermost Bedoulian “White Level” and lowerargasian supposed “Van Gogh” level), in the otherwise homo-eneous marly series (see above). We had previously assumedMoullade et al., 2006, 2008) that the lower Gargasian changeould be the effects in the stratotype of the volcanogenic episodeamed “Van Gogh Level” defined by Dauphin (2002) in theearby Vocontian Basin. However, a volcanic origin for the pre-umed equivalent is not demonstrated in the La Tuilière section,nd the rhythmic repetition of similar – although less intense –oraminiferal crises in the remainder of the lower Gargasianeries may reflect only a Milankovitch-type cyclicity, as may
e the case in the other Aptian type-locality. The zonal calibra-ion made by Kuhnt and Moullade (2007) in La Marcouline ledo the inference that the wavelength of the cyclic fluctuationseen at La Tuilière might be related to 100 ky short eccentricity
orpo


ycles. Similar fluctuations of biological parameters not at alleflected by a very homogeneous lithology were already reportedy Cubaynes et al. (1990) in the Toarcian of SW France. Ata Tuilière a Milankovitch-type basic cyclicity (precessionalycles) is not expressed by the lithostratigraphy, contrary to theassis-La Marcouline section at the same period.

. Discussion and conclusion

To end this study, it is important to point out that this pre-iminary and to some degree pioneering work using quantitative

icropaleontology to study the paleoenvironment of the Aptiantratotypes, although providing some interesting leads, alsoncountered the limitations inherent in this kind of research:

the composition of a sample is an average of the assemblagesrepresenting a more or less long lapse of time; this flaw doesnot facilitate detection of short events or specific momentaryenvironments;the precise ecology of genera and species of fossilforaminifera that lived more than 100 My ago remains insuf-ficiently known. Many factors and parameters are involved,their respective influences are difficult to measure: chemicaland granulometric composition of the sediment, food sup-ply, the trophic and ecologic (endobenthos vs epibenthos)behavior of various taxa, the influence of the variations ofoxygenation of bottom waters and their substrate, etc. . .

In view of these difficulties, it would be illusory and prema-ure to draw definitive conclusions based on the qualitative anduantitative variations in the distribution of benthic foraminiferan the Aptian stratotypes. Furthermore, the samples used in thistudy were collected and some examined for purposes otherhan quantitative studies, like biostratigraphy. However, in spitef these drawbacks, this preliminary examination of benthic andlanktonic foraminifera of the Aptian stratotypes enabled us toring out some interesting data and facts; from this attempt ofnterpretation come working hypotheses, the bases for futureesearch.

The main result is the recognition of a kind of cyclicity, betterxpressed in the Bedoulian at Cassis-la Bédoule and in the Gar-asian at Saint-Saturnin-lès-Apt-La Tuilière, reflected by bothariations in abundance and diversity of benthic and planktonicoraminifera. This cyclicity is less clearly expressed in the moreondensed Gargasian series of Cassis-La Marcouline, whereloser sampling and the inclusion of samples from the morealcareous interbeds would certainly have increased the detailf the findings.

A similar cyclicity was brought to light in the Lower Creta-eous by Michael (1968, Barremian of NW Germany), Coccionind Galeotti (1993, Albian of Central Italy) and Tyszka (2009,lbian of NW Germany). These last two authors suggested that

his cyclicity might be related to variations in the parameters
f the earth’s orbit. These variations would influence climate,unoff, nutrient availability rhythmically, and in turn affect theroductivity of phytoplankton and zooplankton, the usual foodf foraminifera.


Fig. 9. Uppermost Bedoulian and lower Gargasian quantitative data from La Tuilière. CO: colour change; VG: van Gogh level.Données quantitatives du Bédoulien terminal et du Gargasien inférieur de La Tuilière. CO : changement de couleur ; VG : niveau van Gogh.

e mic

esptti(

A

FsmFmwfl

R

B

B

B

B

C

C

C

C

C

D

D

D

D

E

E

E

E

E

F

G

G

H

H

H

H

H

J


Further studies of the Aptian stratotypes should result in anven more precise control of their chronology, which in turnhould give rise to better discrimination, calibration and inter-retation of cyclic variations in the microfauna. To assess betterhe significance and accuracy of results based on biological data,hese variations should also be collated with the climatic cyclic-ty depicted by other methods, such as rock magnetic propertiesKößler et al., 2001).

cknowledgments

We are indebted to Taniel Danelian (University of Lille,rance) who encouraged us to undertake this study and madeuggestions which led to significant improvements to theanuscript, as well as to Bruno Granier (University of Brest,rance) for his advice. We also thank two reviewers, an anony-ous one and Mark Leckie (University of Massachusetts, USA),hose both scientific and linguistic suggestions were very help-

ul, as well as Nestor Sander (Modesto, USA) for his finalinguistic check of the paper.

eferences

abinot, J.F., Moullade, M., Tronchetti, G., 2007. Les Ostracodes du Bédouliensupérieur et du Gargasien inférieur du stratotype de l’Aptien : systéma-tique et corrélations biostratigraphiques. Carnets de Géologie/Notebookson Geology, Article 2007/05 (CG2007 A05), pp. 1–36.

audin, F., Moullade, M., Tronchetti, G., 2008. Characterisation of the organicmatter of upper Bedoulian and lower Gargasian strata in the historicalstratotypes (Apt and Cassis-la-Bédoule areas, SE France). Carnets de Géolo-gie/Notebooks on Geology, Letter 2008/01 (CG2008 L01), pp. 1–9.

ergen, J.A., 1998. Calcareous Nannofossils from the lower Aptian historicalstratotype at Cassis-La Bédoule (SE France). Géologie Méditerranéenne 25,227–255.

réhéret, J.G., 1997. L’Aptien et l’Albien de la fosse Vocontienne (des bor-dures au bassin). Évolution de la sédimentation et enseignements sur lesévénements anoxiques. Publications de la Société Géologique du Nord 25,614.

occioni, R., Galeotti, S., 1993. Orbitally induced cycles in benthonicforaminiferal morphogroups and trophic structure distribution patterns fromthe Late Albian “Amadeus Segment” (Central Italy). Journal of Micropale-ontology 12, 227–239.

onte, G., 1994. La limite Bédoulien-Gargasien dans la coupe stratotypique deCassis-La Bédoule (Bouches-du-Rhône, France). Géologie Alpine, H.S. 20,321–326.

otillon, P., Ferry, S., Gaillard, C., Jautée, E., Latreille, G., Rio, M., 1980.Fluctuation des paramètres du milieu marin dans le domaine vocontien(France SE) au Crétacé inférieur : mise en évidence par l’étude des for-mations marnocalcaires alternantes. Bulletin de la Société géologique deFrance 22 (7), 735–744.

otillon, P., Rio, M., 1984. Cyclic sedimentation in the Cretaceous DSDP sites535 and 540 (Gulf of Mexico), 534 (Central Atlantic) and in the VocontianBasin (France). In: Buffler, R.T., Schlager, W. (Eds.), Initial Reports of theDeep Sea Drilling Project 77, U.S. Government Printing Office, Washington,pp. 339–376.

ubaynes, R., Rey, J., Ruget, C., Courtinat, B., Bodergat, A.M., 1990. Rela-tions between systems tracts and micropaleontological assemblages on aToarcian carbonate shelf (Quercy, southwest France). Bulletin de la Société
géologique de France 6 (8), 989–993.
auphin, L., 2002. Litho-, bio- et chrono-stratigraphie comparées dans le Bassinvocontien à l’Aptien. Thèse de Doctorat, Université de Lille 1 (inédit).

armedru, C., 1982. La microfaune dans les alternances marne – calcaire pélag-iques du crétacé inférieur vocontien (Sud-Est de la France) – Mise en

K


évidence d’oscillations climatiques. Thèse de Doctorat, Université Claude-Bernard Lyon 1.

upont, G., 1980. Les communautés de foraminifères au Barrémien et auBédoulien dans le Bassin vocontien (chaînes subalpines méridionales). Leurévolution lors du passage du bassin aux plate-formes bordières. Consé-quences stratigraphiques et paléoécologiques. Thèse de Doctorat, UniversitéClaude-Bernard Lyon 1 (inédit).

utour, Y., 2005. Biostratigraphie, évolution et renouvellements des ammonitesde l’Aptien supérieur (Gargasien) du bassin vocontien (Sud-Est de la France).Thèse de Doctorat, Université Claude Bernard Lyon 1 (inédit).

rba, E., 1993. The Early Aptian “nannoconid crisis”: a paleobiologic responseto global change. Paleopelagos 3, 59–73.

rba, E., Channell, J.E.T., Claps, M., Jones, C., Larson, R., Opdyke, B., PremoliSilva, I., Riva, A., Salvini, G., Torricelli, S., 1999. Integrated stratigraphyof the Cismon Apticore (Southern Alps, Italy): a “reference section” forthe Barremian-Aptian interval at low latitudes. Journal of ForaminiferalResearch 29, 371–391.

rbacher, J., Gerth, W., Schmiedl, G., Hemleben, C., 1998. Benthic foraminiferalassemblages of late Aptian-early Albian black shale intervals in the Vocon-tian Basin, SE France. Cretaceous Research 19, 805–826.

rbacher, J., Hemleben, C., Huber, B.T., Markey, M., 1999. Correlatingenvironmental changes during early Albian oceanic anoxic event 1Busing benthic foraminiferal paleoecology. Marine Micropaleontology 38,7–28.

rbacher, J., Thurow, J., 1997. Influence of oceanic anoxic events on the evolu-tion of mid-cretaceous radiolaria in the North Atlantic and western Tethys.Marine Micropaleontology 30, 139–158.

riès, G., 1987. Dynamique du bassin subalpin méridional de l’Aptien au Céno-manien. École des Mines de Paris, Mémoires des Sciences de la Terre 4,370 p.

ranier, B., Moullade, M., Ropolo, P., Tronchetti, G., Kuhnt, W., 2008. TheAptian stage: Input from the historical stratotype. 33rd International Geo-logical Congress – Oslo, 2008, abstract.

uérin, S., 1981. Utilisation des foraminifères planctiques et benthiques dansl’étude des paléoenvironnements océaniques au Crétacé moyen : applicationau matériel des forages DSDP de l’Atlantique Nord et Sud. Comparaisonavec la Tethys. Thèse Doctorat, université de Nice, Travaux du centre derecherches micropaléontologiques « Jean Cuvillier » 2, 198 p.

eldt, M., Bachmann, M., Lehmann, J., 2008. Microfacies, biostratigraphy, andgeochemistry of the hemipelagic Barremian-Aptian in north-central Tunisia:Influence of the OAE 1a on the southern Tethys margin. Palaeogeography,Palaeoclimatology, Palaeoecology 261, 246–260.

errle, J.O., Kössler, P., Friedrich, O., Erlenkeuser, H., Hemleben, C., 2004.High resolution carbon isotope records of the Aptian to lower Albian fromSE France and the Mazagan Plateau (DSDP Site 545). A stratigraphic toolfor paleoceanographic and paleobiologic reconstruction. Earth and PlanetaryScience Letters 223, 303–318.

errle, J.O., Mutterlose, J., 2003. Calcareous nannofossils from the Aptian-Lower Albian of southeast France: palaeoecological and biostratigraphicimplications. Cretaceous Research 24, 1–22.

olbourn, A., Kuhnt, W., 2001. No extinctions during oceanic Anoxic Event1b: the Aptian-Albian benthic foraminiferal record of ODP Leg 171. In:Kroon, D., Norris, R.D., Klaus, A. (Eds.), Western North Atlantic Palaeogeneand Cretaceous palaeoceanography. Geological Society of London, SpecialPublications 183, pp. 73–92.

olbourn, A., Kuhnt, W., Soeding, E., 2001. Atlantic paleobathymetry, paleopro-ductivity and paleocirculation in the late Albian: the benthic foraminiferalrecord. Palaeogeography, Palaeoclimatology, Palaeoecology 170,171–196.

enkyns, H.C., 1995. Carbon isotope stratigraphy and paleoceanographic sig-nificance of the Lower Cretaceous shallow water carbonates of ResolutionGuyot, Mid-Pacific Mountains. In: Winterer, E.L., Sager, W., Firth, J., Sinton,J.M. (Eds.), Proceedings of the Ocean Drilling Program, Scientific Results
143, College Station, TX, pp. 99–104.
ößler, P., Herrle, J.O., Appel, E., Erbacher, J., Hemleben, C., 2001.Magnetic records of climatic cycles from mid-Cretaceous hemipelagicsediments of the Vocontian basin, SE France. Cretaceous Research 22,321–331.

2 e mic

K

K

K

L

L

M

M

M

M

M

M

M

M

M

M

M

M

M

M

M

M

M

R

R

R

R

R

T

T

V

W

08 M. Moullade, G. Tronchetti / Revue d

uhnt, W., Moullade, M., 1991. Quantitative analysis of Upper Creta-ceous abyssal agglutinated foraminiferal distribution in the North Atlantic– Paleoceanographic implications. Revue de Micropaléontologie 34,313–349.

uhnt, W., Moullade, M., 2007. The Gargasian (Middle Aptian) of La Mar-couline section at Cassis-La Bédoule (SE France): Stable isotope recordand orbital cyclicity. Carnets de Géologie/Notebooks on Geology, Article2007/02 (CG2007 A02), pp. 1–9.

uhnt, W., Moullade, M., Masse, J.P., Erlenkeuser, H., 1998. Carbon isotopestratigraphy of the lower Aptian historical stratotype at Cassis-La Bédoule(SE France). Géologie Méditerranéenne 25, 63–79.

eary, P.N., Cottle, R.A., Ditchfield, P., 1989. Milankovitch control offoraminiferal assemblages from the Cenomanian of southern England. TerraNova 1, 416–419.

i, Y., Bralower, T., Montanez, I.P., Osleger, D.A., Arthur, M.A., Bice, D.M.,Herbert, T.D., Erba, E., Premoli Silva, I., 2008. Toward an orbital chronologyfor the early Aptian Oceanic Anoxic Event (OAE1a ∼120 Ma). Earth andPlanetary Science Letters 271, 88–100.

agniez-Jannin, F., 1992. Enregistrement de l’eustatisme par les foraminifèresdans les séquences de dépôt du Crétacé inférieur du bassin vocontien(SE de la France). Palaeogeography, Palaeoclimatology, Palaeoecology 91,247–262.

agniez-Jannin, F., Dommergues, J.L., 1994. Foraminifères vs ammonites enfosse vocontienne vers la limite Valanginien-Hauterivien. Comptes Rendusde l’Académie des Sciences de Paris (II) 319, 957–962.

asse, J.P., 1976. Les calcaires urgoniens de Provence (Valanginien-Aptieninférieur). Stratigraphie, paléontologie, les paléoenvironnements et leur évo-lution. Thèse de Doctorat, Université d’Aix-Marseille II (inédit).

asse, J.P., 1998. Sédimentologie du stratotype historique de l’Aptien inférieurdans la région de Cassis – La Bédoule (SE France). Géologie méditer-ranéenne 25, 31–41.

asse, J.P., Machhour, L., 1998. La matière organique dans la série du stratotypehistorique de l’Aptien inférieur de Cassis-La Bédoule (SE France). GéologieMéditerranéenne 25, 55–62.

asse, J.P., Moullade, M., Tronchetti, G., 1998. Cadre régional du stratotype del’Aptien inférieur dans la région de Cassis-La Bédoule (SE France). GéologieMéditerranéenne 25, 11–14.

enegatti, A.P., Weissert, H., Brown, R.S., Tyson, R.V., Farrimoud, P., Strasser,A., Caron, M., 1998. High-resolution �13C stratigraphy through the earlyAptian “Livello Selli” of the Alpine Tethys. Paleoceanography 13, 530–545.

ichael, E., 1968. Variations in the number of species of benthonic Foraminiferain the Barremian of northwestern Germany. Palaeogeography, Palaeoclima-tology, Palaeoecology 4, 287–303.

oreno, J.A., Company, M., Delanoy, G., Grauges, A., Martínez, G., Salas,R., 2007. Precisiones sobre la edad, mediante ammonoideos y nautiloideos,de la Fm, Margas del Forcall en la subcuenca de Oliete (Cadena Ibérica,Espana). Geogaceta 42, 75–78.

oullade, M., 1966. Étude stratigraphique et micropaléontologique du Cré-tacé inférieur de la « fosse vocontienne ». Documents des Laboratoires deGéologie de la Faculté des Sciences de Lyon 15, 1–369.

oullade, M., 1984. Intérêt des petits Foraminifères benthiques « profonds »pour la biostratigraphie et l’analyse des paléoenvironnements océaniquesmésozoïques. In: Oertli, H.J. (Ed.), Benthos’83. IId International Sympo-sium on Benthic Foraminifera, Pau 1983, pp. 429–464.

oullade, M., Tronchetti, G., Balme, C., Kouyoumontzakis, G., 2006. TheGargasian (Middle Aptian) of La Tuilière - St-Saturnin-lès-Apt (area ofthe Aptian historical stratotype, Vaucluse, SE France): geographic setting
and outcrop correlation. Carnets de Géologie/Notebooks on Geology, Letter2006/01 (CG2006 L01), pp. 1–8.
oullade, M., Tronchetti, G., Bellier, J.P., 2005. The Gargasian (MiddleAptian) strata from Cassis-La Bédoule (Lower Aptian historical stratotype,SE France): planktonic and benthic foraminiferal assemblages and bios-

W


tratigraphy. Carnets de Géologie/Notebooks on Geology, Article 2005/02(CG2005 A02), pp. 1–20.

oullade, M., Tronchetti, G., Bellier, J.P., 2008. Associations et biostratigra-phie des Foraminifères benthiques et planctoniques du Bédoulien sommitalet du Gargasien inférieur de La Tuilière - St-Saturnin-lès-Apt (aire strato-typique de l’Aptien, Vaucluse, SE France). Carnets de Géologie /Notebookson Geology, Article 2008/01 (CG2008 A01), pp. 1–50.

oullade, M., Tronchetti, G., Kuhnt, W., Masse, J.P., 1998. Les Foraminifèresbenthiques et planctoniques de la série du stratotype historique de l’Aptieninférieur dans la région de Cassis-La Bédoule (SE France). GéologieMéditerranéenne 25, 187–225.

oullade, M., Tronchetti, G., Kuhnt, W., Renard, M., Bellier, J.P., 2004.The Gargasian (Middle Aptian) of Cassis-La Bédoule (Lower Aptian his-torical stratotype, SE France): geographic location and lithostratigraphiccorrelations. Carnets de Géologie/Notebooks on Geology, Letter 2004/02(CG2004 L02), pp. 1–4.

utterlose, J., Pauly, S., Steuber, T., 2009. Temperature controlled depositionof Early Cretaceous (Barremian-early Aptian) black shales in an epi-continental sea. Palaeogeography, Palaeoclimatology, Palaeoecology 273,330–345.

enard, M., de Rafelis, M., 1998. Géochimie des éléments traces de la phasecarbonatée des calcaires de la coupe du stratotype historique de l’Aptieninférieur dans la région de Cassis-La Bédoule (SE France). GéologieMéditerranéenne 25, 43–54.

enard, M., de Rafélis, M., Emmanuel, L., Beltran, C., Moullade, M.,Tronchetti, G., 2007. Fluctuations of sea-water chemistry during Gar-gasian (Middle Aptian) time. Data from trace-element content (Mg, Sr,Mn, Fe) in hemipelagic carbonates from La Marcouline Quarry (Cassis,SE France). Carnets de Géologie/Notebooks on Geology, Article 2007/03(CG2007 A03), pp. 1–28.

opolo, P., Conte, G., Gonnet, R., Masse, J.P., Moullade, M., 1998. Les faunesd’Ammonites du Barrémien supérieur/Aptien inférieur (Bédoulien) dans larégion stratotypique de Cassis-La Bédoule (SE France) : état des connais-sances et propositions pour une zonation par Ammonites du Bédoulien-type.Géologie Méditerranéenne 25, 167–175.

opolo, P., Conte, G., Moullade, M., Tronchetti, G., Gonnet, R., 2008. TheDouvilleiceratidae (Ammonoidea) of the Lower Aptian historical stratotypearea at Cassis-La Bédoule (SE France). Carnets de Géologie/Notebooks onGeology, Memoir 2008/03 (CG2008 M03), pp. 1–60.

opolo, P., Moullade, M., Gonnet, R., Conte, G., Tronchetti, G., 2006. TheDeshayesitidae Stoyanov, 1949 (Ammonoidea) of the Aptian historicalstratotype region at Cassis-La Bédoule (SE France). Carnets de Géolo-gie/Notebooks on Geology, Memoir 2006/01 (CG2006 M01), pp. 1–46.

ronchetti, G., 1981. Les Foraminifères crétacés de Provence (Aptien-Santonien) – systématique, biostratigraphie, paléoécologie, paléogéogra-phie. Thèse de Doctorat, Université de Provence, Travaux du Laboratoirede Géologie Historique et de Paléontologie 12, 559 p.

yszka, J., 2009. Foraminiferal response to seasonality modulated by orbitalcycles in the Cretaceous mid-latitudes: The Albian record from the LowerSaxony basin. Palaeogeography, Palaeoclimatology, Palaeoecology 276,148–159.

ahrenkamp, V.C., 1996. Carbon isotope stratigraphy of the Upper Kharaiband Shuaiba Formations: implications for the Early Cretaceous evolutionof the Arabian Gulf region. American Association of Petroleum GeologistsBulletin 80, 647–662.

eissert, H., Bréhéret, J.G., 1991. A carbonate carbon-isotope record fromAptian-Albian sediments of the Vocontian trough (SE France). Bulletin de
la Société géologique de France 162, 1133–1140.
eissert, H., Lini, A., 1991. Ice age interludes during the time of Creta-ceous greenhouse climate. In: Müller, D.W., McKenzie, J.A., Weissert, H.(Eds.), Controversies in Modern Geosciences. Academic Press, London, pp.173–191.