Acta Geologica Polonica, Vol. 53 (2003), No. 1, pp. 1-18 Uppermost Cenomanian ammonites from Eure, Haute-Normandie, northwest France W. J. KENNEDY1, P. JUIGNET2 & J. GIRARD3 1Geological Collections, University Museum of Natural History, Parks Road, Oxford OX1 3PW, U.K. 2Département de Géologie, Université, 14032 Caen Cedex, France 3Rue du 8 mai 1945, 76530 Grand-Couronne, France ABSTRACT: KENNEDY, W.J., JUIGNET, P. & GIRARD, J. 2003. Uppermost Cenomanian ammonites from Eure, Haute-Normandie, northwest France. Acta Geologica Polonica, 53 (1), 1-18. Warszawa. Temporary exposures of chalks spanning the Cenomanian – Turonian boundary to the east of Brionne, Eure, Haute- Normandie, France, yielded well-preserved ammonite faunas. The Metoicoceras geslinianum Zone assemblage is: Pseudocalycoceras angolaense (SPAT H , 1931), Sumitomoceras cautisalbae (WRIGHT & KENNEDY, 1981), Calycoceras (Calycoceras) sp. juv., Eucalycoceras pentagonum (JUKES-BROWNE, 1896), Euomphaloceras septemseriatum (CRAGIN, 1893), Metoicoceras geslinianum (D’ORBIGNY, 1850), Hamites cimarronensis (KAUFFMAN & POWELL, 1977), Allocrioceras annulatum (SHUMARD, 1860), and Sciponoceras gracile (SHUMARD, 1860). The succeeding Neocardioceras juddii Zone assemblage is: Thomelites serotinus WRIGHT & KENNEDY, 1981, Neocardioceras juddii juddii (BARROIS & GUERNE, 1878), Neocardioceras juddii barroisi WRIGHT & KENNEDY, 1981, and Thomasites gongilensis (WOODS, 1911). Imprecisely localised are Pachydesmoceras sp., and Nigericeras aff. scotti COBBAN, 1972. The majority of the species are new for northern France, and confirm the northwards extension of typically Tethyan taxa (Thomasites, Nigericeras) into the Boreal region during the uppermost Cenomanian, and previously rec- ognized in southern England, as well as the occurrence of cosmopolitan acanthoceratids well-known at this level in the United States (Pseudocalycoceras, Sumitomoceras). Key words: Ammonites, Cenomanian, Turonian, Cretaceous, France. INTRODUCTION most Cenomanian zones of Metoicoceras geslinianum and Neocardioceras juddii, the latter not previously rec- In the west of the Paris Basin, in the Roumois ognized in the chalks of northwestern France. Many of region between the valleys of the Seine and Risle (Text- the species present are new to the region, and include a fig. 1) exposures of Cenomanian and Turonian chalks range of Tethyan and cosmopolitan taxa. were documented by JUIGNET (1974). Since that account, a temporary exposure at the now obscured Trou Tassin quarry on the plateau east of the Risle, STRATIGRAPHY close to Neuville-du-Bosc (Eure) exposed some tens of metres of chalk during the 1980’s, exploited for agricul- The sequence across the Cenomanian-Turonian tural purposes. One of us (J.G.) collected a suite of boundary interval is shown in Text-fig. 2. The section well-preserved ammonites from the upper part of the compares well with that exposed in the cliffs of Haute- section, which demonstrated the presence of the upper- Normandie at St-Jouin-Bruneval, Antifer-Le Tilleul, 2 W. J. KENNEDY & al. Fig. 1 Locality map for the Brionne area, Eure, Haute-Normandie, France, showing the position of the Trou Tassin Quarry and Fécamp (JUIGNET & BRETON 1994). From bottom Section for the base of the Turonian stage is shown in to top, the sequence is as follows. Text-fig. 3, as is that recognized in Southern England 1. Craie de Rouen (2 m exposed): bioturbated chalk (WRIGHT & KENNEDY 1981, 1984). The definition of the with a line of black flints. The sequence passes up into base of the Turonian Stage adopted here follows that a nodular chalk, terminated by a glauconitized hard- provisionally adopted by the Turonian Working Group ground, equivalent to the hardgrounds Antifer 1 and 2 of the Subcommission on Cretaceous Stratigraphy at its of the regional reference sections. meetings during the Second International Symposium 2. Craie d’Antifer (60 cm): bioturbated chalk with on Cretaceous Stage Boundaries held in Brussels from nodules and glauconitized pebbles resting on the top September 8-16, 1995 (BENGTSON 1996): the first occur- surface of the underlying hardground. The unit is ter- rence of the ammonite Watinoceras coloradoense minated by a hardground that can be correlated with WRIGHT & KENNEDY, 1981, at the base of Bed 86 of the the regional Antifer 3 hardground. This unit yields the Pueblo section. Metoicoceras geslinianum Zone fauna documented The fauna from the Craie d’Antifer is as follows, below. and can be referred to the western European 3. Craie du Cap Fagnet (5.8 m): bioturbated chalks Metoicoceras geslinianum Zone and the coeval United with nodular horizons and incipient hardgrounds, States Western Interior Sciponoceras gracile Zone: notably in the upper part, the latter equivalent to the Pseudocalycoceras angolaense (SPAT H , 1931), regional Fagnet Hardground. Lines of small black flints Sumitomoceras cautisalbae (WRIGHT & KENNEDY, occur in the upper part. The sparsely nodular chalks in 1981), Sumitomoceras cf. conlini (WRIGHT & KENNEDY, the lowest part of the sequence yielded the 1981), Calycoceras (Calycoceras) sp. juv., Eucalycoceras Neocardioceras juddii Zone ammonites described below. pentagonum (JUKES-BROWNE, 1896), Euomphaloceras 4. Craie du Val St-Nicolas (1 m exposed): chalks septemseriatum (CRAGIN, 1893), Metoicoceras geslini- with scattered nodules, common inoceramid debris, anum (D’ORBIGNY, 1850), Hamites cimarronensis and a course of black flints. KAUFFMAN & POWELL, 1977, Allocrioceras annulatum (SHUMARD, 1860), and Sciponoceras gracile (SHUMARD, 1860). Elements of this fauna occur widely in Europe, THE AMMONITE FAUNAS and all but S. cautisalbae occur in the U.S. Gulf Coast and Western Interior, providing an excellent basis for The ammonite zonal sequence across the intercontinental correlation. Cenomanian-Turonian boundary recognized at Pueblo, The ammonites from the basal part of the Craie du Colorado, the candidate Global Boundary Stratotype Cap Fagnet can be referred to the Neocardioceras juddii CENOMANIAN AMMONITES FROM NORTHWEST FRANCE 3 Fig. 2. The Cenomanian-Turonian boundary interval at the Trou Tassin Quarry, Eure, Haute-Normandie, France 4 W. J. KENNEDY & al. Fig. 3. The ammonite zonal sequence across the Cenomanian-Turonian boundary recognised at Pueblo, Colorado, candidate Global Stratotype section for the base of the Turonian Stage, and in southern England Zone: N. juddii juddii (BARROIS & GUERNE, 1878), N. immediately prior to the Metoicoceras geslinianum juddii barroisi WRIGHT & KENNEDY 1981, and Zone (Calycoceras guerangeri Zone in Europe, Thomasites gongilensis (WOODS, 1911). Of particular Metoicoceras mosbyense/Dunveganoceras pondi Zone in interest is the occurrence of Thomasites, a typically the U.S. Western Interior) we see European incursions Tethyan genus of the uppermost Cenomanian and into the Interior, with Protacanthoceras proteus Lower Turonian (CHANCELLOR & al. 1994) which WRIGHT & KENNEDY, 1987, known from the Black spread northwards during the latest Cenomanian, and Hills in the Northern Interior and Calycoceras is frequent in the juddii Zone in southern England (Proeucalycoceras) guerangeri (SPAT H , 1926), (WRIGHT & KENNEDY 1981), and in the northern Eucalycoceras pentagonum, Euomphaloceras euom- Aquitaine (Port-des-Barques, south of La Rochelle, phalum (SHARPE, 1855), and Vascoceras diartianum Charente-Maritime: Oxford University Museum of (D’ORBIGNY, 1850) in New Mexico (KENNEDY & al. Natural History Collections). 1996; COBBAN & al. 1989). The record of Nigericeras aff. scotti COBBAN, 1971, Following this, Metoicoceras and Neocardioceras, is based on a specimen found loose. N. scotti character- present in the Western Interior in the lower Upper izes a narrow interval between the upper Cenomanian Cenomanian spread to Europe and elsewhere. As well juddii Zone and the basal Turonian Watinoceras colora- as this interchange there are other common taxa, doense Zone in the U.S. Western Interior (COBBAN & notably species of Sciponoceras and Euomphaloceras SCOTT 1973), and we presume it to be derived from the that occur in both Europe, the Western Interior and lower part of the Craie du Cap Fagnet; it too is an immi- much of the rest of the world at this time. grant, for Nigericeras is a common element in Tethyan Thomasites, common on the south side of Tethys in Upper Cenomanian faunas (e.g. MEISTER & al. 1992). the Upper Cenomanian of Nigeria other parts of West We have seen no ammonite evidence for the lowest Africa spread northwards into the Anglo-Paris Basin Turonian Watinoceras devonense Zone in the faunas and the Southern Interior for a brief interval in the jud- from the Craie du Cap Fagnet of Trou Tassin, but cor- dii Zone and immediately prior to this. relative sections on the coast yield ammonites of the Lower Turonian Mammites nodosoides Zone some metres above the base of the unit. CONVENTIONS The uppermost Cenomanian faunas from Haute Normandie agree closely with those known from else- Location of specimens: The following abbreviations where in the Anglo-Paris Basin (southern England, are used to indicate the location of specimens men- Boulonnais, Aube), Provence and Germany. They are tioned in the text: particularly characterised by the appearance of a range BMNH: British Museum (Natural History), London of taxa that had been previously restricted to the U.S. BGS: British Geological Survey, Keyworth Western Interior and Gulf Coast regions, as well as JG: Jerome Girard Collection, Museum d’Histoire some Tethyan incursors. This mingling of faunas