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1

Testing the congruence of the macrofossil versus microfossil record in the Turonian-Coniacian boundary succession of the Wagon Mound-Springer composite section (NE New Mexico, USA)

Walaszczyk I., Lees J., Peryt D., Cobban W., Wood C.

Acta Geologica Polonica

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2012

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Vol. 62, no. 4

581-594

EN

The Turonian-Coniacian boundary succession from the Wagon Mound-Springer composite section in the US Western Interior shows a virtually identical macrofaunal record to that revealed in the proposed candidate Coniacian GSSP in the Salzgitter-Salder-Slupia Nadbrzezna composite section in central Europe, with easy identification in both regions of the base of the Coniacian Stage, as defined by the first appearance of the inoceramid bivalve species, Cremnoceramus deformis erectus (Meek). The macrofaunal boundary definition is additionally confirmed by the foraminiferal and nannofossil data, demonstrating the high potential of the inoceramid marker for the base of the Coniacian. The former claims about distinct diachroneity between macrofossil and microfossil dates in the trans-Atlantic correlations, resulted from methodological deficiencies, and have no factual basis.

2

The Salzgitter-Salder Quarry (Lower Saxony, Germany) and Slupia Nadbrzezna river cliff section (central Poland) : a proposed candidate composite Global Boundary Stratotype Section and Point for the Coniacian Stage (Upper Cretaceous)

Walaszczyk I., Wood C., Lees J., Peryt D., Voigt S., Wiese F.

Acta Geologica Polonica

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2010

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Vol. 60, no. 4

445-477

EN

An integrated account of a candidate composite Global Boundary Stratotype Section and Point for the base of the Coniacian Stage, comprising the Salzgitter-Salder Quarry section (Lower Saxony, Germany) and the Słupia Nadbrzeżna river cliff section (central Poland), is provided. Documented are all the main biostratigraphically significant macrofossil and microfossil groups: ammonites, bivalves (inoceramids and the genus Didymotis), planktonic foraminifera and calcareous nannoplankton. also provided are correlations based on stable carbon isotope curves. The base of the Coniacian is defined by the first occurrence (FO) of the inoceramid bivalve Cremnoceramus deformis erectus (Meek, 1876), a cladogenetic successor of the C. waltersdorfensis (Andert, 1911) lineage. This event is well above the first appearance of the classic ammonite marker of this boundary, Forresteria petrocoriensis (Coquand, 1859), which is first noted high in the Upper Turonian Mytiloides scupini inoceramid bivalve zone at Słupia Nadbrzeżna. The boundary at Salzgitter-Salder cannot be precisely defined by means of ammonites; however, there is an apparent local change in one scaphitid lineage a short distance below the boundary. In calcareous nannofossil terms, the boundary falls within the interval between the first occurrence of Broinsonia parca parca and the last occurrence (LO) of Helicolithus turonicus. at present, no planktonic species found in both sections can be used as a close proxy for the base of the Coniacian, as defined by the inoceramid bivalve marker. In terms of carbon stable isotopes, the Turonian Coniacian Boundary lies in the inflection point from falling to rising [delta^13]C values. a comparison of the Salzgitter-Salder and Słupia Nadbrzeżna carbon isotope curves indicates a hiatus at the former locality. The base of the Coniacian in the Salzgitter-Salder section is marked by a flood occurrence of Cremnoceramus deformis erectus, constituting the deformis erectus I event. The boundary interval at Słupia Nadbrzeżna is expanded: here the first occurrence of C. deformis erectus is separated from both the terminal Turonian C. waltersdorfensis waltersdorfensis event and the C. deformis erectus I event, also indicating the existence of a hiatus at the boundary in the Salzgitter-Salder section. In view of this hiatus at the critical level, it is proposed that the two sections should constitute a candidate composite Coniacian GSSP.

3

New observations on the inoceramid biostratigraphy of the higher part of the Upper Turonian and the Turonian - Coniacian boundary transition in Poland, Germany and the UK

Wood C., Walaszczyk I., Mortimore R., Woods M.

Acta Geologica Polonica

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2004

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Vol. 54, no. 4

541-550

EN

New studies of sections in southern England (Bridgewick Pit, Downley, Shoreham Cement Works Quarry), eastern England (Kiplingcotes Station Quarry, Arras Road Pit), Germany (Salzgitter-Salder Quarry, a potential candidate GSSP for the Coniacian Stage) and central Poland (Słupia Nadbrzeżna, another potential candidate GSSP) have enabled a re-evaluation and refinement of the inoceramid biostratigraphy of the higher part of the Upper Turonian and the Turonian-Coniacian boundary transition. The inoceramid record at Słupia Nadbrzeżna below the terminal Turonian entry of Cremnoceramus is shown to be more complete than at the standard Salzgitter-Salder Quarry section. A new inoceramid event (Inoceramus lusatiae Event) identified at Słupia Nadbrzeżna is inferred to be present at the Sonnenberg Quarry, Waltersdorf, the type locality of Inoceramus lusatiae, as well as of I. glatziae and Cremnoceramus waltersdorfensis,and it is possibly represented in the condensed Navigation Hardgrounds in southern England. The absence of this event at Salzgitter-Salder suggests a significant hiatus. An inoceramid assemblage characterised by a taxon of uncertain affinities that immediately precedes the flood occurrence of Cremnoceramus (waltersdorfensis I Event) at Salzgitter-Salder has been identified at a comparable biostratigraphic position in eastern England (Yorkshire) and, tentatively, also in southern England. Inoceramids from this assemblage in the UK had previously been incorrectly assigned to Cremnoceramus waltersdorfensis and the basal Coniacian marker taxon, C. deformis erectus. The position of the base of the Coniacian has accordingly been revised upwards in both the southern and eastern England successions.

4

Early Cenomanian (Cretaceous) inoceramid bivalves from the Kronsberg Syncline (Hannover area, Lower Saxony, Germany) : stratigraphic and taxonomic implications

Wilmsen M., Niebuhr B., Wood C.

Acta Geologica Polonica

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2001

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Vol. 51, nr 2

121-136

EN

An Early Cenomanian inoceramid bivalve assemblage collected from material excavated from a temporary exposure in the Kronsberg Syncline east of Hannover (northern Germany) is described. It consists of "Inoceramus" crippsi MANTELL, 1822, "I" hoppenstedtensis TROGER, 1967, Inoceramus virgatus scalprum BOHM, 1914 and I. virgatus virgatus SCHLUTER, 1877, as well as transitional forms between I. virgatus virgatus and I. virgatus scalprum and an apparently undescribed sulcate form. The inoceramid fauna is well preserved and very rich in individuals. Many of the inoceramids occur either as double-valved individuals or with the valves in close association and appear to be cocentrated in distinct layers. Co-occurring ammonites are Mantelliceras dixoni SPATH, Mantelliceras sp., Schloenbachia varians (J. SOWERBY), Hypoturrilities gravesianus (D'ORBIGNY) and Scaphites obliquus J. SOWERBY. Using event stratigraphy, the stratigraphic interval of the collected fauna can be assigned to the lower part of the Lower Cenomanian Mantelliceras dixoni ammonite Zone. It predominantly comprises material from the Inoceramus virgatus acme-event (the Schloenbachia/virgatus event of German event stratigraphy) at the top of the lower subzone (Mantelliceras dixoni & M. saxbii Subzone) of the dixoni Zone, which is known from the Lower Saxony, Cleveland (eastern England) and Anglo-Paris basins, where it invariably occurs in carbonate-rich rocks with low diversity faunas. The lithofacies and geochemistry of the strata are documented and the "Inoceramus" crippsi and Inoceramus virgatus groups are discussed, including the problematic provenance of the type series of Inoceramus virgatus scalprum.

5

Inoceramids and biostratigraphy at the Turonian/Coniacian boundary; based on the Salzgitter-Salder Quarry, Lower Saxony, Germany, and the Słupia Nadbrzeżna section, Central Poland

Walaszczyk I., Wood C.

Acta Geologica Polonica

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1998

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Vol. 48, no. 4

395-434

EN

The candidate Global Standard Stratotype-section and oint for the base of the Coniacian Stage, the Salzgitter-Salder section, Germany, and the Słupia Nadbrzeżna section, central Poland, provide together a continuous record of the inoceramid succession and events across the Turonian/Coniacian boundary interval, that can be correlated throughout Europe and beyond. The Turonian/Coniacian boundary interval marks a radical change from the Upper Turonian Mytiloides/Inoceramus - dominated fauna to the Cremnoceramus-dominated fauna of the tompost Turonian and Lower Coniacian. The Cremnoceramus clade is basically composed of three lineages: waltersdorfensis, with subspecies waltersdorfensis (ANDERT) and hannovrensis (HEINZ); deformis, with subspecies erectus (MEEK), dobrogensis (SZASZ) and deformis (MEEK); and crassus, with subspecies inconstans (WOODS) and crassus (PETRASCHECK). Rare Inoceramus species range throughout the boundary interval, and in the middle Lower Coniacian representatives of the genus Tethyoceramus SORNAY (non HEINZ) appear. Twelve species and/or subspecies of these genera are described and illustrated. The inoceramids provide the basis for the subdivision of the uppermost Turonian - Lower Coniacian boundary interval into 7 inoceramid zones. The upper Upper Turonian is divided into the Mytiloides scupini Zone and the Cremnoceramus waltersdorfensis Zone. In the Lower Coniacian the following zones are distinguished, in ascendin order: Cremnoceramus deformis erectus, C. waltersdorfensis hannovrensis, Cremnoceramus crassus inconstans, Cremnoceramus crassus + C. deformis deformis and Inoceramus gibbosus. The inoceramid marker proposed for the base of the Coniacian, formerly referred to as Cremnoceramus rotundatus (sensu TROGER non FIEGE) is a synonym of Cremnoceramus erectus (MEEK), and its first appereance marks the base of the deformis erectus Zone and the base of the Coniacian Stage. The Salzgitter-Salder section, despite some problems concerning a possible hiatus or condensation at the boundary represents the best avaiable potential stratotype for the Turonian/Coniacian boundary.