Abstract: The Albian–Cenomanian boundary coincides with a positive stable carbon isotope excursion that previously has been correlated with an oceanic anoxic event (OAE1d); however, there are other secular isotopic excursions associated with the Albian–Cenomanian boundary as well as the Early Cenomanian that are preceded by OAE1d. The focus of this study is Deep Sea Drilling Project (DSDP) Hole 547A (eastern North Atlantic), where multiple isotopic excursions spanning the Albian–Cenomanian boundary and Early Cenomanian have been correlated to the Albian– Cenomanian boundary event (ACBE) and Lower Cenomanian events (LCEs) I to III of the Mont Risou (France), the English Chalk, and Gubbio (Italy) sections using planktonic foraminifera biostratigraphy and stable carbon isotope stratigraphy. Although these excursions are recorded in numerous sections, very little information exists about the triggering mechanisms that led to these perturbations in the carbon cycle. This paper aims to assess the ACBE and LCEs I to III using the calcareous nannofossil assemblages at DSDP Hole 547A to determine stratigraphic changes associated with these excursions. The findings from this study indicate that there were changes in surface water productivity during these excursions, where Biscutum spp. abundances increased at the onset of the excursions, while species evenness and Shannon’s diversity index decreased. Given these findings, it can be inferred that an increase in surface water productivity led to rapid burial of isotopically light carbon, which resulted in the positive stable carbon isotope excursions associated with ACBE and LCEs I to III. It is posited that pulses of intensified mixing occurred along the northwestern African margin during the Late Albian through Early Cenomanian, which caused increased surface water fertility and paleoproductivity. These pulses have been linked to the gradual stabilization of mid-Cretaceous ocean circulation that resulted from plate reorganization and long-term sea-level rise. These events enhanced the connection between different ocean basins, creating a stable circulation mode with well-defined upwelling systems.

Abstract The Cenomanian–Turonian boundary interval of the Arobes section, northern Spain, represents the maximum depth of a relatively shallow succession. The investigated section extends within the Rotalipora cushmani and Whiteinella archaeocretacea planktonic foraminiferal zones, and from UC3 up to UC8 nannofloral zones, respectively. The Oceanic Anoxic Event 2 (OAE2) is about 16 m thick and includes a positive δ 13 C excursion, from 3 up to 5.5‰. The first peak of δ 13 C is situated towards the upper part of the Rotalipora cushmani planktonic foraminiferal zone, while the second peak of δ 13 C is situated in the lower part of the Whiteinella archaeocretacea planktonic foraminiferal zone. The plateau, the youngest phase of OAE2, ends slightly above the first occurrence (FO) of the nannofossil Quadrum gartneri . Based on nannofloral fluctuation, an unstable environment is recognized from the last occurrence (LO) of the nannofossil Axopodorhabdus albianus up to the FO of the nannofossil Quadrum gartneri . Mesotrophic, eutrophic and oligotrophic nannofossils have successive peaks throughout the OAE2. In the lower part of OAE2, especially in the trough phase and second build-up, productivity increased. The calcareous dinoflagellate Thoracosphaera spp. peaks up to almost 30% in the lower part of the second build-up phase. The critical nannofloral turnover episode is characterized by impoverished calcareous nannofossil assemblages and temporary disappearances of high-fertility taxa, such as Biscutum constans and Zeugrhabdotus erectus . This shift in nannofloral assemblages starts in the last stages of OAE2; that is, towards the top of the second build-up phase and also covers the main part of the plateau phase of δ 13 C.

Abstract There is a considerable history of using calcareous microfossils in criminal investigations, and cases all fall into the provenance category. These are cases in which sediments containing calcareous microfossils are associated with a crime scene, but do not necessarily originate in that location. By establishing the provenance of the sediment based on specific characteristic microfossils, the micropalaeontologist is able to assist in the investigation by potentially linking a vehicle and its user with a crime scene. This study examines the use of both foraminifera and calcareous nannoplankton in criminal investigations. It focuses on the importance of both microfossil groups during the police investigation of the Soham murder case in which these microfossils were used to place the suspect’s vehicle at the location where the bodies of the two victims were found. Clear recognition of both the foraminifera and the calcareous nannoplankton on the vehicle as being from a stratigraphically constrained unit of the Cretaceous Grey Chalk, and the establishment of its provenance, were a major element of the prosecution case. Other lithological criteria, including the mineralogy of the chalk and the field evidence regarding access routes and site topography, were also used to exclude alternative potential sources for the chalk on the vehicle.

Abstract Study of the Upper Cretaceous oceanic red beds (CORBs) in the Outer Western Carpathians, Czech Republic, was based on integrated biostratigraphy (foraminifera, dinoflagellata, calcareous nannofossils). Agglutinated foraminifers are the only abundant microfossil group in red shale. Reconstruction of the sedimentary paleoenvironment was supported by mineralogical and paleoichno-logical analysis. Bioturbation and lack of organic matter indicate highl oxic sedimentary conditions. The CORBs range from the Albian to the Lower Paleocene. Both their bases and their tops are heterochronous through individual facies zones of the Outer Carpathians. Generally, the time span of the CORBs decreases from abyssal to slope facies and from inner to outer zones. The CORBs reached their maximum extent during the Turonian. The CORBs were terminated by increased influx of terrigenous organic matter. Key words: Outer Carpathians, red beds, Cretaceous, dinoflagellates, agglutinated foraminifera, calcareous nannofosils, ichnofossils

Abstract The Cenomanian–Turonian carbonate ramp in the Adıyaman Region of SE Turkey (Northern Arabian Platform) records an abrupt shift from benthic carbonate deposits to pelagic deposits near the Cenomanian–Turonian boundary event (CTBE) in the İnişdere stratigraphic section and surrounding borehole sections. A positive δ 13 C excursion of up to 2.15% is recorded in carbonate and organic carbon deposited around the CTBE and provides evidence of a direct link between the CTBE and oceanic anoxic events and the demise of the shallow carbonate production in the Derdere Formation. The microfacies analyses, biostratigraphic dating and palaeoenvironmental interpretations suggest that the platform was drowned near the CTBE as a result of changing environmental conditions. The microfacies indicating significant deepening show a contemporaneity to equivalent surfaces globally and thus strongly support an isochronous formation of Cenomanian–Turonian facies by eustatic sea-level changes. Anoxia spreading over the platform drastically reduced the carbonate production as observed in the studied sections and, therefore, resulted in a reduction in carbonate accumulation rates. Regional/local subsidence and a coeval sea-level rise during the late Cenomanian to early Turonian interval were the cause of the drowning of the platform, including regional anoxia at the northern Arabian platform linked to the Cenomanian–Turonian oceanic anoxic event (OAE2).

Abstract: CORBs are described from a north-south transect from the passive European margin with the Helvetic–Ultrahelveticshelf and continental slope through the Alpine Tethys, including the Rhenodanubian Flysch Zone into the southern, tectonically active margin of the Austro–Alpine microplate, including the Northern Calcareous Alps. In the Helvetic (shelf) and Ultrahelvetic (slope) part of the European margin, the proportion of CORBs in the Upper Cretaceous successions increases significantly with increasing water depth and increasing pelagic character. In the Ultrahelvetic units of Upper Austria (Rehkogelgraben, Buchberg), CORBs define a continuous red interval from the Lower Turonian to the Lower Campanian. The onset of CORB deposition in the Ultrahelvetic Zone corresponds to a major change in paleoceanographic conditions from anoxic during the Late Cenomanian OAE 2 to highly oxic during the Early to Middle Turonian. In the Rhenodanubian Flysch, hemipelagic red and green shales alternate with turbiditic siltstones and minor sandstones in the Upper Aptian–Lower Cenomanian Lower Varicolored Marls, the Coniacian–Lower Campanian Seisenburg Formation, and the uppermost Campanian Perneck Formation. CORBs in the Rhenodanubian Flysch are controlled mainly by tectonic events and sea-level changes, and occur during times of transgressions, low clastic input, and low turbidite frequencies. In the Austro–Alpine Northern Calcareous Alps, CORBs occurfrom the Santonian onwards in the upper parts of transgressive sequences of the Gosau Group, e.g., in the Tiefenbach and the Dalsenalm sections. In areas where clastic input was low, CORB deposition continued up into the Maastrichtian. Based on these data a peak of oceanic red beds is inferred for the middle Santonian–Early Campanian time interval. Prerequisites for CORB sedimentation are low clastic input, low sedimentation rates, and increasing paleo–water depth. CORBs can be classified as a variation of three end members: clayey CORBs, consisting mainly of terrigenous clay minerals; calcareous CORBs, mainly pelagic limestones; and siliceous CORBs, consisting mainly of biogenic SiO 2 .

Abstract The 130-year history of study of the Cenomanian–Turonian Eagle Ford and Woodbine Groups of Texas has created a complicated and often confusing nomenclature system. Deciphering these nomenclatures has frequently been hindered by outdated biostratigraphic studies with inaccurate age interpretations. To resolve these issues, a comprehensive compilation and vetting of available biostratigraphic, geochemical, and lithologic data from Eagle Ford and Woodbine outcrops and subsurface penetrations was undertaken, which was then tied to a large network of wells in both south and east Texas. Composite sections were built for four outcrop areas of central and north Texas (Dallas, Red River, Waco, Austin), five outcrop areas from west Texas (Langtry, Del Rio, Big Bend, Chispa Summit, Quitman Mountains), four subsurface areas from south Texas (Webb County, Atascosa County, Karnes County, DeWitt/Gonzales Counties), and two cross sections from the east Texas subsurface (basin center and eastern margin). The resulting datasets were utilized to construct age models and characterize depositional environments, including paleoceanography. In agreement with previous studies, the total organic carbon (TOC)-rich Lower Eagle Ford was interpreted to have been deposited under anoxic to euxinic conditions and the Upper Eagle Ford under dysoxic to anoxic conditions. The Oceanic Anoxic Event 2 (OAE2) interval is missing at all locations north of Atascosa County; when present it is characterized as having been deposited under oxic to suboxic conditions. High abundances of radiolaria and calcispheres identified within recrystallized medial to distal limestones of the Lower Eagle Ford indicated limestone formation during periods of enhanced water-column mixing and increased primary productivity, in contrast to proximal limestones composed of planktonic foraminifera and inoceramid prisms concentrated by bottom currents. Standardized nomenclature systems and age models are proposed for each of the outcrop and subsurface areas. Proposed changes to existing nomenclatures include reassignment of the Tarrant Formation of the Eagle Ford to the Lewisville Formation of the Woodbine in the Dallas area and the Templeton Member of the Lewisville Formation to the Britton Formation of the Eagle Ford in the Red River area. The proposed term “Waller Member” of Fairbanks (2012) for the former Cloice Member of the Lake Waco Formation in the Austin area is recognized with a new stratotype proposed and described, although the Waller Member is transferred to the Pepper Shale Formation of the Woodbine. The Terrell Member is proposed for the carbonate-rich section at the base of the Boquillas Formation in the Langtry and Del Rio areas, restricting the Lozier Canyon Member to the organic-rich rocks underlying the Antonio Creek Member. The south Texas subsurface is divided into the Upper Eagle Ford and Lower Eagle Ford Formations, with the clay-rich Maness Shale Member at the base of the Lower Eagle Ford and the foraminifera grainstone dominated Langtry Member at the top of the Upper Eagle Ford. Use of the term “middle Eagle Ford” for the clay-rich facies south of the San Marcos arch is not recommended.