Avant-propos

Avant-propos

AVANT-PROPOS FOREWORD N. N E U M A N N & R. S C H R O E D E R M. N E U M A N N & R. SCHROEDER Au Cr6tac6 moyen (en particulier pendant l'Albien et...

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AVANT-PROPOS

FOREWORD

N. N E U M A N N & R. S C H R O E D E R

M. N E U M A N N & R. SCHROEDER

Au Cr6tac6 moyen (en particulier pendant l'Albien et le C6nomanien) des plates-formes carbonat6es prennent une tr~s grande extension dans la r6gion m6diterran6enne. La faune benthique de ce milieu particulier est caract6ris6e surtout par des grands Foraminif~res dont les repr6sentants les plus importants peuvent parfois ~tre si abondants qu'ils forment l'essentiel du s6diment.

During the Middle Cretaceous (and particularly during the Albian and the Cenomanian), carbonated platforms developed considerably in the Mediterranean region. Benthic fauna in this particular environment is mainly characterised by larger Foraminifera, the most important of which may be considered as rock-builders as they are so abundant.

Les Ammonites et Foraminif6res planctoniques marqueurs pr6cieux pour les d6pSts p61agiques - sont g6n6ralement absents ou tr6s rares darts le milieu n6ritique. Pour cette raison les grands Foraminif~res, dont la valeur stratigraphique est incontest6e depuis longtemps, jouent un r61e important pour la datation des plates-formes carbonat6es. Bien que plusieurs auteurs aient d6j~ propos6 des 6chelles r6gionales de r6partition avec des r6sultats souvent contradictoires, il manquait jusqu'ici une synth6se critique de toutes les donn6es particuli~res, valables dans un vaste domaine. Les grands Foraminif+res sont des organismes structure interne souvent tr6s complexe dont l'interpr6tation est parfois assez difficile. Pour cette raison, il n'est pas 6tonnant que de nombreuses esp~ces soient encore mal d6finies ou insuffisamment connues. Une bonne d6finition des taxa est donc la base principale pour fixer leur r6partition stratigraphique. Conscients de cette situation, M. Neumann (Paris) et R. Schroeder (Frankfurt) ont d6cid6 en 1978 de constituer un groupe de travail dans le cadre du Working Group 9 du projet I.G.C.P. ~ Mid Cretaceous Events ~. Ce groupe a rassembl6 des sp6cialistes europ6ens, universitaires et p6troliers, pour 6laborer un

The valued pelagic deposit markers such as Ammonites and/or planktonic Foraminifera are usually absent or very rare in neritic environments. Therefore, larger Foraminifera whose stratigraphical importance is no longer to be argued, play a significant role in enabling carbonated platforms to be dated. Although several authors have already suggested regional chronostratigraphical ranges with often controversial results, a critical synthesis of all the relevant data, valid for a wide area, has been lacking up until now. Larger Foraminifera are organisms which often have a complex internal structure and which can be quite difficult to interpret. It is not surprising, therefore, that numerous species still remain poorly defined or insufficiently described. A good definition of taxa is thus the principal basis on which to determine their stratigraphic distribution. Several European university and oil specialists, aware of this, formed a group in 1978 headed by M. Neumann (Paris) and R. Schroeder (FrankfurO, within the activities o f Working Group 9 o f the L G. C.P. project ~ Mid-Cretaceous Events ~, to draw up a catalogue of species and a chronostratigraphic

catalogue d'espbces et un tableau de r6partition stratigraphique des grands Foraminif~res du Cr6tac6 moyen de la r6gion m6diterran6enne. Participent h ce (( Groupe de Travail europ6en des grands Foraminif6res ) ) : A . Arnaud-Vanneau (Grenoble), P.-Y. Berthou (Paris), L. Brun (Boussens), A. Cherchi (Cagliari; secr6taire du groupe), M. Chiocchini (Camerino), P. De Castro (Napoli), E. Fourcade (Paris), A. Garcia Quintana (Madrid), M. H a m a o u i (Pau), M. Lamolda (Bilbao), E. Luperto Sinni (Bari), M. Neumann (Paris), B. Prestat (Boussens), R. Schroeder (Frankfurt) et G. Tronchetti (Marseille). Les probl6mes pal6ontologiques et stratigraphiques ont 6t6 discut6s au cours de 5 r6unions : 1 - Paris (2 novembre 1978) : buts et modalit6s de travail. Etablissement d'une liste de grands Foraminif6res h 6tudier ;

range chart o f Larger Foraminifera in the Mediterranean region during the Middle Cretaceous. Participating in this European Working Party on larger Foraminifera are: .4. Arnaud-Vanneau (Grenoble, France), P.-Y. Berthou (Paris), L. Brun (Boussens, France), A. Cherchi (Cagliari, Italy ; group secretary), M. Chiocchini (Camerino, Italy), P. De Castro (Napoli, ltaly), E. Fourcade (Paris), A. Garcia Quintana (Madrid), M. Hamaoui (Pau, France), M. Lamolda (Bilbao, Spain), E. Luperto Sinni (Bari, Italy), M. Neumann (Paris), B. Prestat (Boussens, Prance), R. Schroeder (Frankfurt, W. Germany) and G. Tronchetti (Marseille, France). Paleontological and stratigraphical issues have been discussed at .five meetings as follows : 1 - Paris (2nd November 1978) : aims and methods of work. Establishment of a list of larger Foraminifera to be discussed and studied ;

2 - Paris (13-14 novembre 1979) : s6ance sur le genre Orbitolina (pr6sent6 par R. Schroeder) ;

2 - Paris (13th - 14th November 1979) : conference on the genus Orbitolina (presented by R. Schroeder) ;

3 - Pau (18-19 d6cembre 1979) : s6ance sur les genres Nezzazata, Biconcava, Biplanata, Merlingina, Trochospira, Reticulinella (pr6sent6s par M. Hamaoui) ; Broeckina (par A. Cherchi et R. Schroeder) ; Cyclopsinella (par A. Cherchi) ;

3 - Pau (18th - 19th December 1979) : conference o f the genera Biconcava, Biplanata, Merlingina, Trochospira, Nezzazata and Reticulinella (presented by M. Hamaoui) ; Broeckina (presented by A. Cherchi and R. Schroeder) ; Cyclopsinella (presented by A. Cherchi) ;

4 - Napoli (28-29 f6vrier 1980) : s6ance sur les Alv6olinid6s de la M6diterran6e centrale et orientale (Ovalveolina p.p., Sellialveolina, Cisalveolina) (pr6sent6s par P. De Castro) ; les Alv6olinid6s de la M6diterran6e occidentale (Ovalveolina p.p., Praealveolina (par M. Neumann) ; Pseudedomia (par M. Hamaoui)

4 - Napoli (28th - 29th February 1980) : conference on the Alveolinidae o f the middle and western Mediterranean (Ovalveolina p.p., Praealveolina) (presented by M. Neumann), and Pseudedomia (presented by M. Hamaoui) ;

5 - Frankfurt (24-25 avril 1980) : s6ance sur les Orbitolinid6s primitives (Neoiraqia, ~ Valdanchella ~, Simplorbitolina, Neorbitolinopsis, Paracoskinolina, Coskinolinella) (pr6sent6s par R. Schroeder) ; P6n6roplid6s (par. P. De Castro) ; Chrysalidina (par M. Neumann & P. De Castro) ; Praechrysalidina (par E. Luperto Sinni).

5 - Frankfurt (24th - 25th April 1980) : conference on primitive Orbitolinidae (Neoiraqia, ~ Valdanchella ~, Simplorbitolina, Neorbitolinopsis, Paracoskinolina and Coskinolinella) (presented by R. Schroeder) ; Peneroplidae (presented by P. De Castro) ; Chrysalidina (presented by M. Neumann and P. De Castro) ; Praechrysalidina (presented by E. Luperto Sinni).

Au cours de ces r6unions chaque esp6ce a fait l'objet d'une mise au point par un rapporteur sp6cialis6 dans l'6tude de ce taxon. Une discussion cons6cutive au rapport a permis d ' a p p o r t e r parfois des d6tails suppl6mentaires. L'attribution g6n6rique actuelle des diff6rentes espbces n ' a pas 6t6 discut6e, car elle doit reposer sur la discussion d'esp6ces/l extension d6bordant l'espace de temps envisag6.

During these meetings, each species was presented by the ~ specialist ~ o f the particular taxon. A discussion following the report between the members o f the group present sometimes brought to light additional details which have altered or emended the original diagnosis. However, the real generic attribution o f the different genera was not dealt with ; such a project must take into account species which extend beyond the space o f time we intended to study.

La r6partition stratigraphique propos~e pour chaque esp~ce, fond6e soit sur des propres observations, soit sur des donn6es sores extraites de la litt6rature (contr616es par la pr6sence d ' A m m o n i t e s ou de Foraminif6res planctoniques) a dt6 6galement discut6e. Ainsi le r6sultat final peut s'appuyer sur les observations et exp6riences de tout le groupe. Le r6sultat de nos efforts a 6t6 consign6 darts deux publications : 1 - Le ~ Tableau de r6partition stratigraphique des grands Foraminif~res du Cr6tac~ m o y e n de la r6gion m~diterran6enne ~ a 6t6 6labor6 par tous les membres du groupe. R. Schroeder a present6 ce tableau au X X V I I ~ Congr~s-Assembl6e pl6ni6re de la Commission Internationale pour l'exploration scientifique de la M6diterran6e (Cagliari 1980 ; Rapp. C o m m . int. Mer M6dit., vol. 27, n ~ 8, p. 121-123, Monaco 1981) et /l la Conference Internationale du projet MidCretaceous Events (Uppsala 1981). Une version plus 61abor6e avec les r6f6rences bibliographiques les plus importantes a 6t6 publi6e dans la revue ~< Cretaceous Research )), vol. 2, p. 383-393 (Uppsala 1981).

The stratigraphical distribution o f each species based either on personal observations, or on data taken from reliable sources (corroborated by the presence o f Ammonites and/or planktonic Foraminifera) was equally discussed by the other members. Thus the final result is based upon the observations and experiences o f the whole group. The results o f our efforts have been set out in two publications : 1 - The ~ Stratigraphical distribution chart o f Middle Cretaceous larger Foraminifera in the Mediterranean region ~ which was drawn up by all the members o f the group. R. Schroeder presented this chart at the 27th plenary Congress-Assembly o f the International Commission for scientific exploration in the Mediterranean (Cagliari, 1980) and at the International Conference of the project Mid-Cretaceous Events (Uppsala, 1981). A more detailed version containing the most important biostratigraphical references has been published in the periodical ~ Cretaceous Research ~, vol. 2, pp. 383-393 (Uppsala, 1981).

Le tableau pr6sent6 dans ce pr6sent volume (tabl. 1 ; p. 9) correspond en substance ~ celui d6jh publi6 en 1980/1981 mais il s'en distingue par deux 616ments :

The distribution chart presented in this volume (p. 9) corresponds essentially to that already published in 1980/1981 but differs from it on two points :

- la r6partition stratigraphique de plusieurs esp6ces (marqu6es par un ast6risque) a 6t6 16g~rement modifi6e par le rapporteur ;

- the stratigraphical distribution o f several species (indicated by an asterisk) has been slightly modified by the corresponding author ;

- plusieurs esp6ces (marqu6es par un rectangle) ont 6t6 6tudi6es et ajout6es au tableau ult6rieurement.

- several species (indicated by a rectangle) have been studied and added later to the distribution chart.

2 - Le pr6sent volume sur ~ Les grands Foraminif6res du Cr~tac~ m o y e n de la r~gion m6diterran6enne >7 a 6t6 ~labor6 par les membres du groupe qui ont pr6sent6 les esp~ces ~ chacune des r6unions. Chaque auteur a repris les d6finitions et les figurations originales et dans la plupart des cas a apport6 une contribution personnelle sous forme d'observations compl6mentaires relatives soit it des d6tails de structure, soit it des pr6cisions stratigraphiques. Pour cette raison les auteurs sont responsables de mises au point pr6sent6es pour chacune des esp~ces.

2 - Thepresent volume o f ~ The Middle Cretaceous larger Foraminifera in the mediterranean region ~ was drawn up by the members of the group who presented the species at each meeting. Each author reviewed the original descriptions and in most cases has brought a personal complementary contribution and new observations. These are either related to anatomical details or stratigraphical emendations. Therefore each author is responsible f or his own subject entry.

L'id6e premiere 6tait de constituer un catalogue des diff6rentes esp6ces. Tr6s rite il nous est apparu que le travail personnel de chacun des auteurs d6passait le cadre de la r6alisation d'une telle pr6sentation. Aussi cette publication correspond en fait a une v6ritable r~vision des taxa et non pas it une simple compilation de faits d6jfi publi6s. De plus, dans la plupart des cas,

The original idea was to prepare a catalogue o f the different species studied. However, it soon became apparent that the author's work had in fact been overlooked. The present publication is therefore not only a mere compilation of data already known but is indeed a substantial revision of the given taxa. Moreover, most o f the species dealt with here are abundantly illustrated, thus supplying additional and detailed complementary information.

l'illustration est tr6s abondante, apportant des pr6cisions sur la structure de ces diff6rentes esp6ces, par rapport aux publications ant6rieures. Les esp6ces 6tudi6es appartiennent aux Lituolidae, Ataxophragmiidae, Nezzazatidae, Barkerinidae, Orbitolinidae, Soritidae et Alveolinidae. A l'int6rieur de chacune de ces families, les esp+ces ont 6t6 class6es la plupart du temps par ordre de complexit6 croissante. Ce m6moire, regroupant des esp6ces bien d6finies morphologiquement et dont l'extension stratigraphique a 6t6 pr6cis6e, constitue doric un outil de travail fondamental ~ des fins syst6matiques et stratigraphiques. Nous regrettons de n'avoir pas pris en consid6ration plusieurs groupes parfois tr6s fr6quents comme les Cuneolines, Dicyclines, Dictyopsella, etc... Ces formes posent encore des probl6mes d'ordre structural et taxonomique et feront l'objet d'6tudes ult6rieures. La publication de ce m6moire a 6t6 rendue possible grace/t l'aide financi6re du C.N.R.S. et d'Elf Aquitaine qu'il nous est agr6able de remercier.

The studied species belong to the families Lituolidae, Ataxophragmiidae, Nezzazatidae, Barkerinidae, Orbitolinidae, Soritidae and Alveolinidae. The species are presented within each of these families according to the increasing complexity of their anatomy. This publication gathers together morphologically well defined species, the stratigraphical range of which has been emphasized. It is therefore a fundamental and practical tool both for systematic studies and in chronostratigraphy. We are unfortunately unable to produce a similar study of some other groups which may frequently occur in the Mediterranean Middle Cretaceous deposits such as Cuneolina spp., Dicyclina spp., Dictyopsella spp. and others. These forms are still be subject of anatomical and taxonomical problems to be solved. They will, however, be dealt with in the near future. We gratefully acknowledge the sponsoring of this publication by the C.N.R.S. and Elf Aquitaine.

ALBIEN.

?

ESPECES

CENOMANIEN ITURO NIEN moyenlsuD.

~Coski~*olinella d ~ o i . ; S[mplorDit~fina ma~asi o

Orbitelina (iV/,) texatta

o

=Preechry~alidi~a

~~

infracretac~,~

Orbitofine (M.) subconcava =Sabaudia minute aChare~tia c~v[/ilez; aCo~:kinoHneJla sa~tanderensis ~DJotyoconus" pvre~aicu~ S[mplorbit~ii~ze eo~ulu~ aCu~-kinolfnel/a navarrens[s

l

NeorbitoJiHQp~/c co~olus Orbitolina (M.) aperta =Ot'hilOi~n~ (0 } sefin~ *Neoiraqia convexa Dictyocot~u~ (C-) ca~tcrasi OrJ~tc;Jina (C,) cr Orbitoiino (0./durgtlddelgaf =-

='~

=

N~zzazat~ sJtr~p/~x =Neoiraoia msolita "'Valda~chell~ ~ derco~lrti ~-P ~ r O p t i ~ p~r~tS

;a "~_

~.

~'

=Sellialveohna viallii =O t b j t o l i n a (C) corbarica ~Ov~[veolina cr~ss~ ~OvoIv~ol[tla tD~ccagnoae Orbitoima dC_)conica Orbitotina fO.) ceecava Broeckjna (R) biplane

t~

*PraeaJveo)[~o I~erico ~

reich~l~

Ptaealveolinu simplex ~ Z~ax]a ~;erlomana *Nezzazata gr # y ~

l

Ps~udorhapydionJna dubia T [ o e h o s p i ~ avna~eiechi Biconcave b e n t o r i Btplanata peneroplifozn~is ~M a y n c i n a ~rbignyi Pseudedot~Ja d r o r i ~ n ~ } $ ~Cyc/oJlnD czetace~ Cyclopsinefla n e . m a n n a e Ou~lvP.olin~ ~ v ~ r ~ Ch[vsaJidf~g 9 t a d ~ t ~ * Precalvco/i~o c r c t e c c e c~r~lv~t[I]~

pet~ne~Jsss

c Pr~eal~eoJin~ brevi~ Merlin~ina cretocee

~

p

u

l

~

* Cisaiueoflna / ' r a ~ Pseudorttapyd/ont~ 'faurinen~l~ Broeckino (PJ ba(canica

"Pteeatveofh~ tet~uis Pse~dorhipidfonfna r =CJJ~<~lV~of~rl~ f F ~ J R~r

~eiChel~

--I ITI