Johan Vellekoop

KU Leuven

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Robert P. Speijer

KU Leuven

Philippe Claeys

Vrije Universiteit Brussel

Jan Smit

Vrije Universiteit Amsterdam

Lineke Woelders

Institute of Arctic and Alpine Research

Pim Kaskes

Vrije Universiteit Brussel

Appy Sluijs

Utrecht University

Matthias Sinnesael

Université Paris Sciences et Lettres

Henk Brinkhuis

Utrecht University

Niels J. de Winter

Vrije Universiteit Brussel

Sierra Petersen

University of Michigan–Ann Arbor

Cooperative Institutions

KU Leuven

International Ocean Discovery Program

Utrecht University

Vrije Universiteit Brussel

Vrije Universiteit Amsterdam

Continental (Canada)

Royal Netherlands Institute for Sea Research

Centre National de la Recherche Scientifique

Goethe University Frankfurt

Planetary Science Institute

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Rapid short-term cooling following the Chicxulub impact at the Cretaceous–Paleogene boundary

Proceedings of the National Academy of Sciences (2014)

Johan Vellekoop Appy Sluijs Jan Smit Stefan Schouten Johan W.H. Weijers

Significance Here, for the first time (to our knowledge), we are able to demonstrate unambiguously that the impact at the Cretaceous–Paleogene boundary (K–Pg, ∼66 Mya) was followed by a so-called “impact winter.” This impact winter was the result of the injection of large amounts of dust and aerosols into the stratosphere and significantly reduced incoming solar radiation for decades. Therefore, this phase will have been a key contributory element in the extinctions of many biological clades, including the dinosaurs. The K–Pg boundary impact presents a unique event in Earth history because it caused global change at an unparalleled rate. This detailed portrayal of the environmental consequences of the K–Pg impact and aftermath aids in our understanding of truly rapid climate change.

Paleogene

Global cooling

Ozone Depletion

10.1073/pnas.1319253111

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Citations (210)

DEEP-MARINE RECORDS OF DECCAN TRAP VOLCANISM BEFORE, DURING, AND AFTER THE CRETACEOUS–PALEOGENE (K-PG) MASS EXTINCTION

Abstracts with programs - Geological Society of America (2021)

Lawrence Percival Matthias Sinnesael Toni Schulz Johan Vellekoop Steven Goderis

Deccan Traps

Paleogene

10.1130/abs/2021am-368317

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Inter- and intra-chamber variability of trace elements in benthic foraminifera – potential and risks of LA-ICP-MS analyses

Monika Doubrawa Peter Stassen Marci M. Robinson Robert P. Speijer Johan Vellekoop

The Mg/Ca ratio of foraminiferal tests is widely used to reconstruct seawater temperature in past climates. With traditional methods (i.e. Inductively Coupled Plasma Optical Emission Spectrometry or ICP-OES), multiple tests have to be clustered together to attain enough material for analysis. The need for high amounts of carbonate can be problematic for shelf sediments if suitable foraminifera are scarce. As a consequence, grouping of different taxa into one bulk value or ‘sample grouping’ is applied, losing information on interspecific and intra-specimen geochemical variability. Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) solves this problem by targeting extremely small surfaces, e.g., single foraminifer tests or even single chambers.Nevertheless, understanding LA-ICP-MS-generated foraminiferal Mg/Ca records requires in-depth knowledge on the growth and reproductive cycle of extinct foraminiferal taxa, such as Cibicidoides sp. and Anomalinoides acutus from the Paleocene-Eocene transition and early Eocene. These species are commonly used for environmental reconstruction because they are thought to have incorporated the ocean water chemistry in equilibrium with their tests, yet not much is known about their life or precipitation cycle.The reproductive cycle of modern benthic foraminifera ranges from a few weeks to a year, depending on species and size, requiring about a single day to precipitate a new chamber. This implies a potential change in geochemistry from chamber to chamber. Hence, LA-ICP-MS hypothetically allows for an extremely high-resolution, in situ Mg/Ca record across a year, or a precipitation season, if sufficient snapshots of chamber calcification moments are incorporated. As a result, a comparison of cyclic temperature changes on both annual (seasonal variations across individual specimens of a sample) and sub-millennial (variations across closely spaced samples) scale could be feasible. However, the complex growth of the foraminiferal test (e.g. layering due to overgrowth of older chambers) likely also results in geochemical variability within chambers.Here we investigate the inter- and intra-chamber variability in Mg/Ca composition of extinct benthic foraminifera using LA-ICP-MS. We evaluate the resulting potential and risks stemming from inhomogeneous trace-element distribution in the tests. We utilize foraminiferal tests from shelves from the western North Atlantic and the North Sea Basin, covering a paleodepth transect (

TRACE (psycholinguistics)

10.5194/egusphere-egu24-3059

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Palynology from ground zero of the Chicxulub impact, southern Gulf of Mexico

Palynology (2020)

Vann Smith Sophie Warny Johan Vellekoop Vivi Vajda Gilles Escarguel

Palynological analysis of Site M0077A in the Chicxulub impact crater has yielded a record of the immediate Cretaceous/Paleogene (K/Pg) recovery from ground zero of the end-Cretaceous mass extinction, followed by a record of the Paleocene–Eocene Thermal Maximum (PETM) and later Ypresian (Eocene), including the Early Eocene Climatic Optimum (EECO). Eight specimens of the dinoflagellate cyst Trithyrodinium evittii have been observed near the base of the K/Pg transitional unit; these likely represent a post-impact dinoflagellate disaster recovery assemblage deposited within several days following the impact, although the possibility that some or all of the T. evittii specimens are reworked Maastrichtian cysts cannot be fully excluded. Despite high-resolution sampling of the lowermost Paleocene successions, the oldest identifiable terrestrial palynomorphs observed in the Site M0077A core, two specimens of Deltoidospora fern spores, occur at least ∼200,000 years after the impact. Other than these occurrences, the Paleocene section is nearly barren in terms of palynomorphs, likely a result of poor preservation of organic material combined with a long recovery time for vegetation in the vicinity of the crater. Pollen and fungal spore concentrations spike in an anoxic dark shale deposited during the PETM around 56 Ma, with a diverse pollen assemblage indicating the presence of a coastal shrubby tropical forest in the geographic vicinity, likely in the Yucatán Peninsula to the south. In the marine realm, this interval is characterized by thermophilic assemblages of dinoflagellate cysts. Stratigraphically constrained cluster analysis identified four statistically robust sample clusters in the lower Eocene successions, with Malvacipollis spp. and Milfordia spp. abundances driving the highest average dissimilarity between clusters. A second notable spike in palynological concentrations above the PETM section may represent another early Eocene hyperthermal event. Pollen and plant spore concentrations generally increased during the EECO, associated with increases in terrestrial input during basin infilling.

Paleogene

Dinoflagellate

10.1080/01916122.2020.1813826

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A chemostratigraphic framework for the type-Maastrichtian

Johan Vellekoop Pim Kaskes Matthias Sinnesael John W.M. Jagt Robert P. Speijer

<p>The youngest time interval of the Cretaceous Period is known as the Maastrichtian, a reference to the marine strata exposed in the area surrounding the city of Maastricht, in the Netherlands-Belgium border region. The stratigraphic succession at the original type-locality of the Maastrichtian (ENCI quarry, NL) only covers the upper part of the Maastrichtian Stage as it is nowadays defined. However, in combination with similar rock sequences in several other quarries (e.g. Hallembaye, Curfs) in the region, a substantial part of the Maastrichtian Stage is represented.</p><p>While the type-Maastrichtian strata have provided a wealth of paleontological data, comparatively little geochemical work has been carried out on this succession. So far, the age assessment of, and stratigraphic correlation with, the type-Maastrichtian has been largely based on biostratigraphy and preliminary attempts at cyclostratigraphy, techniques that are hampered by bioprovincialism and the presence of stratigraphic gaps in the succession. In recent years, stable carbon isotope stratigraphy has been proven to be a powerful tool for correlating Upper Cretaceous strata on a global scale. When calibrated with biostratigraphic events, carbon isotope stratigraphy can be used to test the synchroneity of bio-events and reconcile inter-regional biostratigraphic schemes. Therefore, we have generated the first high-resolution stable carbon isotope stratigraphy for the type-Maastrichtian, using the extensive sample set acquired in the context of the Maastrichtian Geoheritage Project. In combination with elemental data generated using &#181;XRF (e.g. Ca, Si, Al, Ti, Fe wt%), our record presents the first high-resolution chemostratigraphy for the type-Maastrichtian. This new chemostratigraphic framework enables us to refine the age-model for studied strata, and allows a better regional and global correlation with the type-Maastrichtian successions, placing the paleontological records from the type-Maastrichtian in a global context. &#160;</p>

Cyclostratigraphy

Sequence Stratigraphy

10.5194/egusphere-egu2020-13863

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Cretaceous-Paleogene boundary impact winter superimposed on long-term climate changes

AGU Fall Meeting Abstracts (2014)

Johan Vellekoop Jan Smit Appy Sluijs Henk Brinkhuis Selen Esmeray‐Senlet

Paleogene

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Iridium profiles and delivery across the Cretaceous/Paleogene boundary

Earth and Planetary Science Letters (2016)

Selen Esmeray‐Senlet Kenneth G. Miller Robert M. Sherrell Turgay Senlet Johan Vellekoop

Paleogene

10.1016/j.epsl.2016.10.010

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A high-resolution record of environmental changes from a Cretaceous-Paleogene section of Seymour Island, Antarctica

Palaeogeography Palaeoclimatology Palaeoecology (2020)

Roberto A. Scasso Mercedes B. Prámparo Johan Vellekoop Corina Franzosi Liliana Norma Castro

Dinocyst

Paleogene

10.1016/j.palaeo.2020.109844

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Citations (27)

Robust multi-proxy data integration, using late Cretaceous paleotemperature records as a case study

Earth and Planetary Science Letters (2018)

Lineke Woelders Johan Vellekoop Gert Jan Weltje Lennart de Nooijer Gert‐Jan Reichart

Paleoclimatology

Proxy (statistics)

10.1016/j.epsl.2018.08.010

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Citations (37)

Bryozoan assemblages of the Gulpen Formation (upper Campanian – upper Maastrichtian) in the Liège-Limburg area (Belgium, the Netherlands)

Netherlands Journal of Geosciences – Geologie en Mijnbouw (2024)

Oliver Kesselhut Luc Goffings Johan Vellekoop

Abstract Renewed interest in bryozoan assemblages from the various members of the Gulpen Formation (upper Campanian–upper Maastrichtian) in the Liège-Limburg area (southeast Netherlands and northeast Belgium) during recent years has resulted in the discovery of a number of species previously unrecorded from the area. Nineteen species are here recorded from the Zeven Wegen, Vijlen, Lixhe and Lanaye members (Gulpen Formation) in the study area, occurring in three distinct assemblages. The vast majority of the bryozoan taxa belong to the order Cheilostomata; only two taxa are assigned to the order Cyclostomata. The species recorded here are Clinopora aff. costulata, Disporella obvallata, ‘Vincularia’ ( sensu lato ) marssoniana, Herpetopora laxata, Heteroconopeum ovatum, Wilbertopora aff. oxyteichos, Biaviculigera sacerdotalis, Semiflustrella britannica, Aechmellina anglica, Escharifora papyracea, Onychocella cyclostoma, Onychocella cylindrica, Onychocella matrona, Rhebasia disparilis, Stichomicropora sicksi, Coscinopleura elegans, Coscinopleura lamourouxi, Pachydermopora pachyderma and Beisselina aviculifera. While not previously recorded from the Liège-Limburg area, the bryozoan taxa identified from the Gulpen Formation are well known from coeval Cretaceous strata elsewhere in Europe, North America and Russia, highlighting their broad palaeobiogeographical distribution.

10.1017/njg.2024.14

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