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As a result of a lithological, sedimentological and biostratigraphic study of well sections from the Danish sector of the North Sea, including some recently drilled exploration wells on the Ringkøbing–Fyn High, the lithostratigraphic framework for the siliciclastic Palaeogene to Lower Neogene sediments of the Danish sector of the North Sea is revised. The sediment package from the top of the Chalk Group to the base of the Nordland Group is subdivided into seven formations containing eleven new members. The existing Våle, Lista, Sele, Fur, Balder, Horda and Lark Formations of previously published lithostratigraphic schemes are adequate for a subdivision of the Danish sector at formation level. Bor is a new sandstone member of the Våle Formation. The Lista Formation is subdivided into three new mudstone members: Vile, Ve and Bue, and three new sandstone members: Tyr, Idun and Rind. Kolga is a new sandstone member of the Sele Formation. Hefring is a new sandstone member of the Horda Formation. Freja and Dufa are two new sandstone members of the Lark Formation. Danish reference sections are established for the formations, and the descriptions of their lithology, biostratigraphy, age and palaeoenvironmental setting are updated.

Abstract: A new dinoflagellate zonation scheme for the New Zealand Arowhanan Stage (upper Cenomanian–lower Turonian) is proposed based on a study of the dinoflagellate assemblage from four onshore East Coast Basin sections, including the boundary stratotype section for the Arowhanan Stage. The existing Endoceratium ludbrookiae Zone is emended; its top now coincides approximately with the base of the Arowhanan Stage, at the highest occurrence of Endoceratium turneri. Three new interval zones are proposed above it: Ascodinium serratum Zone, Cyclonephelium clathromarginatum Zone and Hapsocysta peridictya Zone. The three zones together cover all but the uppermost part of the Arowhanan Stage. The Cenomanian/Turonian (C/T) stage boundary is located above the top of the Hapsocysta peridictya Zone, below the Arowhanan/Mangaotanean stage boundary. The boundary between the inoceramid bivalve Magadiceramus rangatira haroldi Zone and Magadiceramus rangatira rangatira Zone, which informally subdivides the Arowhanan into lower and upper substages, is located in the upper part of the Cyclonephelium clathromarginatum Zone. The distribution pattern of key dinoflagellate taxa in the Mangaotane Stream section indicates that the C/T boundary interval may be condensed or missing from that section. The new dinoflagellate Pareodinia mangaotanensis, which is restricted to the Arowhanan Stage, is described from the sections. [Copyright &y& Elsevier]

Abstract: Stratigraphic sections across the Cenomanian/Turonian boundary (C/T boundary) are identified in New Zealand and were deposited in southern high latitudes of the palaeo-Pacific. Lithological evidence for Cretaceous Oceanic Anoxic Event 2 (OAE2), which preceded and spanned the C/T boundary, is lacking in these sections. The correlative interval is identified, however, from a positive 2‰ carbon isotope excursion (CIE) and from clustered highest occurrences of Cenomanian-restricted dinoflagellate taxa together with the lowest occurrence of Turonian Heterosphaeridium difficile. A zone lacking benthic macrofossils encompasses the CIE. In some sections, this interval is also characterized by distinctive red mudstone beds; the thickest such red bed (6–18m thick) may overlap or just overlie the main part of the CIE interval. Shelly macrobenthos, notably inoceramid bivalves, disappeared >500kyr prior to the CIE. This suggests that environmental deterioration associated with OAE2 may have preceded the inferred volcanic trigger that has been identified from other regions. Strong intermediate water depth oxia during OAE2, which contrasts with oceanic anoxic conditions that occurred elsewhere on the globe, apparently prevailed during the later phase of OAE2 in the southernmost Pacific. New data from New Zealand indicate that causal mechanism(s) of OAE2 may be complex. [Copyright &y& Elsevier]

Abstract: High-resolution carbon isotope stratigraphy of the upper Campanian–Maastrichtian is recorded in the Boreal Realm from a total of 1968 bulk chalk samples of the Stevns-1 core, eastern Denmark. Isotopic trends are calibrated by calcareous nannofossil bio-events and are correlated with a lower-resolution δ13C profile from Rørdal, northwestern Denmark. A quantitative approach is used to test the reliability of Upper Cretaceous nannofossil bio-events and provides accurate biohorizons for the correlation of δ13C profiles. The Campanian–Maastrichtian boundary (CMB) is identified through the correlation of dinoflagellate biostratigraphy and δ13C stratigraphy between Stevns-1 and the Global boundary Standard Stratotype-section and Point at Tercis les Bains (SW France), allowing the identification of new chemical and biostratigraphic markers that provide a precise placement of the stage boundary on a regional scale. The boundary interval corresponds to the third phase of a stepwise 0.8‰ negative δ13C excursion, lies in calcareous nannofossil subzone UC16dBP, and encompasses the last occurrence of nannofossil Tranolithus stemmerikii and first occurrence of nannofossil Prediscosphaera mgayae. Fifteen δ13C events are defined and correlated to sixteen reliable nannofossil biohorizons, thus providing a well-calibrated standard high-resolution δ13C curve for the Boreal Realm. [Copyright &y& Elsevier]