The Global Boundary Stratotype Section and Point (GSSP) for the base of the Albian Stage, of the Cretaceous, the Col de Pré-Guittard section, Arnayon, Drôme, France

Following the unanimous approval of the Executive Committee on the International Union of Geological Sciences as notified on April 8, 2016, the Global boundary Stratotype Section and Point for the base of the Albian Stage of the Cretaceous is defined at the first occurrence datum of the planktonic foraminiferan Microhedbergella renilaevis Huber and Leckie, 2011 at a level 37.4 meters above the base of the Marnes Bleues Formation and 40 cm above the base of the Niveau Kilian marker bed in the section SSE of the Col de Pré-Guittard, Arnayon, Drôme, France. The first occurrence of Microhedbergella renilaevis is placed within a 100-m section of argillaceous sediments with 28 secondary markers including calcareous nannofossils, planktonic foraminifera, an inoceramid bivalve, ammonites, stable carbon isotopes, and local marker beds

Pforams@microtax: Anew online taxonomic database for planktonic foraminifera

A new relational taxonomic database for planktonic foraminifera (“pforams@mikrotax�) has been constructed and is now freely available online at http://www.mikrotax.org. It represents amajor advance from its predecessor, the CHRONOS online taxonomic database, which has served the research community since 2005. The benefits of the new database to the research and industrial biostratigraphic communities are many, as it will serve as an immediately accessible taxonomic guide and reference for specialists and non-specialists alike by providing access to a wealth of information and images from original authors and from expertswho have inserted recent authoritative updates to planktonic foraminiferal taxonomy, phylogeny and biostratigraphy. The database will be continually updated and used as a guide for training current and future generations of students and professionals who will be able to self-educate on planktonic foraminiferal taxonomy and biostratigraphy. Further investigation of species traditionally included in the Cretaceous genera Heterohelix, Globigerinelloides, Marginotruncana, and Globotruncana is required to exclude the use of polyphyletic morphotaxa. The taxonomy for Paleogene planktonic foraminifera is quite stable following publication of the Paleocene, Eocene, and Oligocene taxonomic atlases, but revisions to the taxonomy and phylogeny of Neogene taxa are needed to incorporate results from genetic sequencing studies and recent biostratigraphic observations

Long-term Late Cretaceous oxygen-and carbonisotope trends and planktonic foraminiferal turnover: A new record from the southern midlatitudes

© 2016 Geological Society of America. The ~35-m.y.-long Late Cretaceous greenhouse climate has been the subject of a number of studies, with emphasis on the Cenomanian-Turonian and late Campanian-Maastrichtian intervals. By contrast, far less information is available for the Turonian-early Campanian interval, even though it encompasses the transition out of the extreme warmth of the Cenomanian-Turonian greenhouse climate optimum and includes an ~3-m.y.-long mid-Coniacian-mid-Santonian interval when planktonic foraminifera underwent a large-scale, but poorly understood, turnover. This study presents ~1350 δ18O and δ13C values of wellpreserved benthic and planktonic foraminifera and of the <63 μm size fraction from the Exmouth Plateau off Australia (eastern Indian Ocean). These data provide: (1) the most continuous, highly resolved, and stratigraphically well-constrained record of longterm trends in Late Cretaceous oxygen-and carbon-isotope ratios from the southern midlatitudes, and (2) new information on the paleoecological preferences of planktonic foraminiferal taxa. The results indicate persistent warmth from the early Turonian until the mid-Santonian, cooling from the mid-Santonian through the mid-Campanian, and short-term climatic variability during the late Campanian-Maastrichtian. Moreover, our results suggest the cause of Coniacian-Santonian turnover among planktonic foraminifera may have been the diversification of a temperature-and/or salinity-tolerant genus (Marginotruncana), and the cause of the Santonian-early Campanian extinction of Dicarinella and Marginotruncana may have been surface-ocean cooling and competition with globotruncanids

Evidence for global cooling in the Late Cretaceous

PublishedArticleThe Late Cretaceous ‘greenhouse’ world witnessed a transition from one of the warmest climates of the past 140 million years to cooler conditions, yet still without significant continental ice. Low-latitude sea surface temperature (SST) records are a vital piece of evidence required to unravel the cause of Late Cretaceous cooling, but high-quality data remain illusive. Here, using an organic geochemical palaeothermometer (TEX86), we present a record of SSTs for the Campanian–Maastrichtian interval (~83–66 Ma) from hemipelagic sediments deposited on the western North Atlantic shelf. Our record reveals that the North Atlantic at 35 °N was relatively warm in the earliest Campanian, with maximum SSTs of ~35 °C, but experienced significant cooling (~7 °C) after this to <~28 °C during the Maastrichtian. The overall stratigraphic trend is remarkably similar to records of high-latitude SSTs and bottom-water temperatures, suggesting that the cooling pattern was global rather than regional and, therefore, driven predominantly by declining atmospheric pCO2 levels.We gratefully acknowledge funding from the German Science Foundation (DFG Research Stipend Li 2177/1-1 to C.L.), a Royal Society (UK) URF (S.A.R.), a NERC (UK) grant (J.A.L.), a NERC (UK) studentship (K.L.), The Curry Fund of UCL (C.L.), the Cushman Foundation for Foraminiferal Research (J.M. Resig Fellowship to F.F.) and the Spanish Ministerio de Ciencia e Innovación project CGL2011-22912, co-financed by the European Regional Development Fund (I.P.-R., J.A.A., J.A.L.). We thank T. Dunkley-Jones and J. Young for assistance in collecting the samples and S. Schouten for providing TEX86L data from Demerara Rise. This paper is dedicated to Ernie Russell, who sadly died after submission of the manuscript

Planktonic foraminifera

Planktonic foraminifera are marine protozoa with a calcareous and chambered test. The group evolved since late Early Jurassic, and from mid-Cretaceous onward, it has significantly proliferated and is a major component of oceanic oozes. Planktonic foraminifera phylogeny often is closely linked to paleoceanographic turn-over events, and its detailed biostratigraphy contributes significantly to Earth’s geologic history

State of the Science: Mesozoic climates and oceans – a tribute to Hugh Jenkyns and Helmut Weissert

The study of past greenhouse climate intervals in Earth history, such as the Mesozoic, is an important, relevant, and dynamic area of research for many sedimentary geologists, geochemists, palaeontologists and climate modellers. The Mesozoic sedimentary record provides key insights into the mechanics of how the Earth system works under warmer conditions, providing examples of natural climate change and perturbations to ocean chemistry, including anoxia, that are of societal relevance for understanding and contextualizing ongoing and future environmental problems. Furthermore, the deposition of widespread organic-carbon-rich sediments (“black shales”) during the Mesozoic means that this is an era of considerable economic interest. In July 2015, an international group of geoscientists attended a workshop in Ascona, Switzerland to discuss all aspects of the Mesozoic world and to celebrate the four-decade-long contributions to our understanding of this fascinating era in Earth history made by Hugh Jenkyns (University of Oxford) and Helmut Weissert (ETH Zurich). This volume of Sedimentology arose from that meeting and contains papers inspired by (and co-authored by!) Hugh and Helmi. Here a brief introduction to the volume is provided that reviews aspects of Hugh and Helmi's major achievements; contextualizes the papers of the Thematic Issue; and discusses some of the outstanding questions and areas for future research

An integrated study (inoceramid bivalves, ammonites, calcareous nannofossils, planktonic foraminifera, stable carbon isotopes) of the Ten Mile Creek section, Lancaster, Dallas County, north Texas, a candidate Global boundary Stratotype Section and Point for the base of the Santonian Stage

The WalMart section on Ten Mile Creek, Lancaster, Dallas County, Texas, exposes a 23 metre section of Austin Chalk that can be integrated into a more than 60 m composite sequence for the Dallas area on the basis of bed-by-bed correlation. The section was proposed as a possible candidate Global Boundary Stratotype at the 1995 Brussels meeting on Cretaceous Stage boundaries, with the first occurrence of the inoceramid bivalve Cladoceramus undulatoplicatus (Roemer, 1852) as the potential boundary marker. An integrated study of the inoceramid bivalves, ammonites, planktonic foraminifera, and calcareous nannofossils; places the first occurrence of CI. undulatoplicatus in a matrix of ten ancillary biostratigraphic markers. The candidate Global boundary Stratotype Section and Point (GSSP) is located within a composite stable carbon isotope curve for the Austin Chalk as a whole. This shows it to lie 3.5 m below the Michel Dean stable carbon isotope event, originally recognised in the English Chalk. The first occurrence of Cl. undulatoplicatus lies in the same position in relation to stable carbon isotope events in both Texas and England that can in principle be recognised globally in marine sediments. The WalMart section satisfies many of the criteria required of a GSSP for the base of the Santonian Stage, although ownership and access require clarification

Basal Supplementation of Insulin Lispro Protamine Suspension Versus Insulin Glargine and Detemir for Type 2 Diabetes Meta-analysis of randomized controlled trials

OBJECTIVE-We compared the effect of insulin lispro protamine suspension (ILPS) with that of insulin glargine and insulin detemir, all given as basal supplementation, in the treatment of patients with type 2 diabetes. RESEARCH DESIGN AND METHODS-We conducted an electronic search until February 2012, including online registries of ongoing trials and abstract books. All randomized controlled trials comparing ILPS with insulin glargine or detemir with a duration of >= 12 weeks were included. RESULTS-We found four trials lasting 24-36 weeks involving 1,336 persons: three studies compared ILPS with glargine, and one trial compared ILPS with detemir. There was no significant difference in change in HbA(1c) level between ILPS and comparators, in the proportion of patients achieving the HbA(1c) goals of <= 6.5 or <7%, in weight change, or in daily insulin doses. There was no difference in overall hypoglycemia, but nocturnal hypoglycemia occurred significantly more with ILPS than with comparator insulins (mean difference 0.099 events/patient/30 days [95% CI 0.03-0.17]). In a prespecified sensitivity analysis comparing data obtained in patients who remained on their once-daily insulin regimen, not significantly different event rates for nocturnal hypoglycemia were observed between ILPS and comparator insulins (0.063 [-0.007 to 0.13]), and ILPS was associated with lower insulin dose (0.07 units/kg/day [0.05-0.09]). CONCLUSIONS-There is no difference between ILPS and insulin glargine or detemir for targeting hyperglycemia, but nocturnal hypoglycemia occurred more frequently with ILPS than with comparator insulins. Nocturnal hypoglycemia was not significantly different in people who injected insulin once daily

The Bottaccione section at Gubbio, central Italy: a classical Paleocene Tethyan setting revisited

This is the final version of the article. Available from Borntraeger Science Publishers via the DOI in this record.The Upper Cretaceous to Paleocene succession cropping out at the Bottaccione section (Gubbio, central Italy) represents a classical Tethyan setting that served as a standard for the construction of the geomagnetic polarity time scale. Available biomagnetostratigraphy suggests that the Danian interval of the Bottaccione section is condensed relative to other outcrops in the area and/or might contain a non-identified stratigraphic gap. By contrast, a new high-resolution integrated stratigraphic record presented here, including bio-, magneto-, chemo-, and cyclostratigraphy, provides evidence that the Bottaccione record is complete and comparable to other successions outcropping in the Umbria-Marche. However, the paleomagnetic signal of this classical section is partially corrupted in the upper Danian. Recognition of orbitally-forced sedimentary cycles, corresponding to the long eccentricity (405 kyr), and litho- and biostratigraphic correlation with the nearby Contessa Highway which provides a robust magnetostratigraphic record, allows a cyclochronological comparison with ODP Sites 1209 and 1262 and the Zumaia land-based succession. Cycle counting suggests the presence of 10 long-eccentricity cycles between the Cretaceous/Paleogene (K/Pg) boundary and the top C27n event, which has implications for the age of the latter chronohorizon.This research benefitted from funds provided by MIUR-PRIN grant 2010X3PP8J_005 to SG. We thank Dyke Andreasen and Chih-Ting Hsieh for assistance with stable isotope analyses. We are grateful to two anonymous reviewers and to the editor whose comments and criticism contributed to improve much an earlier draft of the paper

Carbon-isotope stratigraphy of the Cenomanian-Turonian Oceanic Anoxic Event: correlation and implications based on three key-localities

We present new, detailed carbon-isotope records for bulk carbonate, total organic carbon (TOC) and phytane from three key sections spanning the Cenomanian-Turonian boundary interval (Eastbourne, England; Gubbio, Italy; Tarfaya, Morocco), with the purpose of establishing a common chemostratigraphic framework for Oceanic Anoxic Event (OAE) 2. Isotope curves from all localities are characterized by a positive carbon-isotope excursion of c. 4 for TOC and phytane and c. 2.5 for carbonate, although diagenetic overprinting appears to have obliterated the primary carbonate carbon-isotope signal in at least part of the Tarfaya section. Stratigraphically, peak ä13C values for all components are followed by intervals of high, near-constant ä13C in the form of an isotopic plateau. Recognition of an unambiguous return to background ä13C values above the plateau is, however, contentious in all sections, hence no firm chemostratigraphic marker for the end-point of the positive isotopic excursion can be established. The stratigraphically consistent first appearance of the calcareous nannofossil Quadrum gartneri at or near the Cenomanian-Turonian boundary as established by ammonite stratigraphy, in conjunction with the end of the ä13C maximum characteristic of the isotopic plateau, provides a potentially powerful tool for delimiting the stratigraphic extent and duration of OAE 2. This Oceanic Anoxic Event is demonstrated to be largely, if not wholly, confined to the latest part of the Cenomanian stag