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Etienne Steurbaut - One of the best experts on this subject based on the ideXlab platform.
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depositional changes during the Danian selandian transition in loubieng france zumaia spain and sidi nasseur tunisia insights from and limits of rock magnetism
Geological Magazine, 2019Co-Authors: Sébastien Wouters, Johan Yans, Simo Spassov, Mathieu Martinez, Etienne Steurbaut, Jean-yves Storme, Xavier DevleeschouwerAbstract:Depositional changes are studied in three sections encompassing the Danian–Selandian transition, Loubieng (France), Zumaia (Spain) and Sidi Nasseur (Tunisia), using magnetic susceptibility as a proxy. Additional rock-magnetic analyses are used to avoid ambiguous interpretation of magnetic susceptibility. The magnetic susceptibility, measured on 90 to 270 samples per section, is mainly controlled by paramagnetic minerals and linked to detrital input. Major increases in the detrital input are correlated to the end of the Latest Danian Event, a hyperthermal, and to the Danian–Selandian boundary. In Loubieng, two gradual increases in magnetic susceptibility within limestones beds precede the major detrital input increases, and start synchronously with the beginning of the Latest Danian Event and the onset of haematite deposition around the Danian–Selandian boundary, respectively. This haematite is suspected to be of primary origin based, among other things, on low magnetic viscosity values, which is used here as an indicator of diagenetic origin in haematite and goethite. The red levels where haematite is interpreted to be of primary origin could be linked to the hyperthermal event previously hypothesized for the basal Selandian. The comparison of the magnetic susceptibility, chemo- and biostratigraphic data between the three sections highlights the condensed nature of the sedimentation around the Danian–Selandian boundary in the sections of the Atlantic realm. The lower part of the Selandian shows a particularly low sedimentation rate at Zumaia compared to Loubieng and Sidi Nasseur. The latter displays the most complete record of the three.
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Tethys. Special reference to the Lowest Occurrence of planktic
2016Co-Authors: J. Sprong, Robert P Speijer, Etienne SteurbautAbstract:Biostratigraphy of the Danian/Selandian transition in the souther
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biostratigraphy of the Danian selandian transition in the southern tethys special reference to the lowest occurrence of planktic foraminifera igorina albeari
Geologica Acta, 2009Co-Authors: J. Sprong, Robert P Speijer, Etienne SteurbautAbstract:The P3a/P3b subzonal boundary is delineated by the lowest occurrence of Igorina albeari. Using literature, identification of the first representatives of I. albeari appeared to be very confusing. In this study descriptions of I. albeari are compared and a consistent definition is proposed. Igorinid specimens with an incipient keel are considered to be I. albeari. Flattening of the last chambers and the fusion of muricae on the peripheral margin may indicate such a slight keel. This keel enables an unambiguous distinction between I. pusilla and the first form of I. albeari and is in keeping with the original descriptions without introducing an intermediate species. In the southern Tethys, the lowest occurrence of I. albeari occurs just prior to the pinkish-brown marl bed in Egypt and immediately overlies the glauconitic bed in Tunisia. Furthermore, the NTp7A/NTp7B subzonal boundary, delineated by the lowest occurrence of Chiasmolithus edentulus, is in close correlation with these marker beds. In Egypt C. edentulus appears 1 m below the entry of I. albeari, whereas in Tunisia they coappear. This implies significant erosion at the glauconitic bed in the studied parts of the Tunisian Trough and a more complete succession at the dark-brown marl bed in the Nile Valley. These marker beds can also be correlated to a level of minor lithologic change in the upper part of the Danian Limestone Formation in the Zumaia section through the lowest occurrence of Chiasmolithus edentulus. The distinct lithologic change in Zumaia, from the Danian Limestone to the Itzurun Formation, however, appears to be ~600 kyr younger than what we now call upper Danian event beds, in Tunisia and Egypt.
Jeanmichel Pacaud - One of the best experts on this subject based on the ideXlab platform.
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revision des mollusques du danien paleocene inferieur du bassin de paris 1 gastropoda patellogastropoda et vetigastropoda pro parte
Geodiversitas, 2004Co-Authors: Jeanmichel PacaudAbstract:The Danian molluscan fauna from the Paris Basin presents a chronological interest of first importance for the understanding of the diversification of European marine ecosystems at the beginning of the Cenozoic. The method consisting in the study of all external prints of molluscs from silicone rubber casts reveals an unexpected faunal diversity. The systematics of 23 species of Patellogastropoda and Vetigastropoda (pro parte) from the Danian perireefal limestone of Vigny (Val-d'Oise, France) and other Danian localities of the Paris Basin are presented here. This study will be completed by further papers in which the Danian molluscan fauna will be revised. Ten new species are described and included in the families Acmaeidae (Scurria dysporista n. sp., Scurriopsis deretrana n. sp.), Fissurellidae (Emarginula (s.s.) horrida n. sp., E. (s.s.) minacis n. sp., E. (s.s.) eucosmia n. sp., E. (s.s.) cavernosa n. sp., Entomella necopinata n. sp., Hemitoma (Montfortia) davincii n. sp., Clypidina (Montfortula) celinae n. sp.) and Pleurotomariidae (Leptomaria meyeri n. sp.). Nine species are reported for the first time from the Danian of Paris Basin (Acmaea simplex, Patella vincenti, Proscutum montense n. comb., Emarginula (s.s.) coralliora, E. (s.s.) montensis, Diodora corneti, D. dolloi, D. concentrica, Praescissurella corneti). Emarginula cretacea d'Orbigny, 1850 is considered a nomen dubium. A new species from the Thanetian of Bioues (Haute-Garonne, France), Emarginula (s.s.) villattae n. sp., is introduced and Emarginula (s.s.) jagti n. nom. is proposed as a replacement name for Emarginula radiata Binkhorst, 1861 non Adams, 1851.
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revision des mollusques du danien paleocene inferieur du bassin de paris 1 gastropoda patellogastropoda et vetigastropoda pro parte
Geodiversitas, 2004Co-Authors: Jeanmichel PacaudAbstract:The Danian molluscan fauna from the Paris Basin presents a chronological interest of first importance for the understanding of the diversification of European marine ecosystems at the beginning of the Cenozoic. The method consisting in the study of all external prints of molluscs from silicone rubber casts reveals an unexpected faunal diversity. The systematics of 23 species of Patellogastropoda and Vetigastropoda (pro parte) from the Danian perireefal limestone of Vigny (Val-d'Oise, France) and other Danian localities of the Paris Basin are presented here. This study will be completed by further papers in which the Danian molluscan fauna will be revised. Ten new species are described and included in the families Acmaeidae (Scurria dysporista n. sp., Scurriopsis deretrana n. sp.), Fissurellidae (Emarginula (s.s.) horrida n. sp., E. (s.s.) minacis n. sp., E. (s.s.) eucosmia n. sp., E. (s.s.) cavernosa n. sp., Entomella necopinata n. sp., Hemitoma (Montfortia) davincii n. sp., Clypidina (Montfortula) celinae n. sp.) and Pleurotomariidae (Leptomaria meyeri n. sp.). Nine species are reported for the first time from the Danian of Paris Basin (Acmaea simplex, Patella vincenti, Proscutum montense n. comb., Emarginula (s.s.) coralliora, E. (s.s.) montensis, Diodora corneti, D. dolloi, D. concentrica, Praescissurella corneti). Emarginula cretacea d'Orbigny, 1850 is considered a nomen dubium. A new species from the Thanetian of Bioues (Haute-Garonne, France), Emarginula (s.s.) villattae n. sp., is introduced and Emarginula (s.s.) jagti n. nom. is proposed as a replacement name for Emarginula radiata Binkhorst, 1861 non Adams, 1851.
Xavier Devleeschouwer - One of the best experts on this subject based on the ideXlab platform.
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depositional changes during the Danian selandian transition in loubieng france zumaia spain and sidi nasseur tunisia insights from and limits of rock magnetism
Geological Magazine, 2019Co-Authors: Sébastien Wouters, Johan Yans, Simo Spassov, Mathieu Martinez, Etienne Steurbaut, Jean-yves Storme, Xavier DevleeschouwerAbstract:Depositional changes are studied in three sections encompassing the Danian–Selandian transition, Loubieng (France), Zumaia (Spain) and Sidi Nasseur (Tunisia), using magnetic susceptibility as a proxy. Additional rock-magnetic analyses are used to avoid ambiguous interpretation of magnetic susceptibility. The magnetic susceptibility, measured on 90 to 270 samples per section, is mainly controlled by paramagnetic minerals and linked to detrital input. Major increases in the detrital input are correlated to the end of the Latest Danian Event, a hyperthermal, and to the Danian–Selandian boundary. In Loubieng, two gradual increases in magnetic susceptibility within limestones beds precede the major detrital input increases, and start synchronously with the beginning of the Latest Danian Event and the onset of haematite deposition around the Danian–Selandian boundary, respectively. This haematite is suspected to be of primary origin based, among other things, on low magnetic viscosity values, which is used here as an indicator of diagenetic origin in haematite and goethite. The red levels where haematite is interpreted to be of primary origin could be linked to the hyperthermal event previously hypothesized for the basal Selandian. The comparison of the magnetic susceptibility, chemo- and biostratigraphic data between the three sections highlights the condensed nature of the sedimentation around the Danian–Selandian boundary in the sections of the Atlantic realm. The lower part of the Selandian shows a particularly low sedimentation rate at Zumaia compared to Loubieng and Sidi Nasseur. The latter displays the most complete record of the three.
Zorina S. - One of the best experts on this subject based on the ideXlab platform.
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Comment on "Danian/Selandian unconformity in the central and southern Western Desert of Egypt" by S. Farouk and A. El-Sorogy [J. Afr. Earth Sci. 103 (2015) 42-53]
2020Co-Authors: Ruban D., Zorina S.Abstract:© 2015 Elsevier Ltd. In their recent paper, Farouk and El-Sorogy (2015) present a reconstruction of the Danian-Selandian relative sea-level changes for the Western Desert of Egypt and an interpretation of eustatic versus tectonic controls on the latter. However, the relative sea-level changes should be distinguished from the shoreline shifts (also for the purposes of inter-regional comparisons). From three alternative global curves, two confirm the authors' conclusions, although it is questionable whether these curves are suitable for the purposes of such an analysis. It cannot be excluded that the relative sea-level fall in the late Danian was caused by the same regional tectonic uplift that resulted in the hiatus at the Danian/Selandian boundary. More research (including quantitative palaeobathymetric modelling) is necessary to understand the relative importance of the eustatic and tectonic controls on the sea-level changes established in the Western Desert of Egypt
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Comment on “Danian/Selandian unconformity in the central and southern Western Desert of Egypt” by S. Farouk and A. El-Sorogy [J. Afr. Earth Sci. 103 (2015) 42–53]
2020Co-Authors: Ruban D., Zorina S.Abstract:© 2015 Elsevier LtdIn their recent paper, Farouk and El-Sorogy (2015) present a reconstruction of the Danian–Selandian relative sea-level changes for the Western Desert of Egypt and an interpretation of eustatic versus tectonic controls on the latter. However, the relative sea-level changes should be distinguished from the shoreline shifts (also for the purposes of inter-regional comparisons). From three alternative global curves, two confirm the authors’ conclusions, although it is questionable whether these curves are suitable for the purposes of such an analysis. It cannot be excluded that the relative sea-level fall in the late Danian was caused by the same regional tectonic uplift that resulted in the hiatus at the Danian/Selandian boundary. More research (including quantitative palaeobathymetric modelling) is necessary to understand the relative importance of the eustatic and tectonic controls on the sea-level changes established in the Western Desert of Egypt
Eustoquio Molina - One of the best experts on this subject based on the ideXlab platform.
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microfossil turnover across the uppermost Danian at caravaca spain paleoenvironmental inferences and identification of the latest Danian event
Palaeogeography Palaeoclimatology Palaeoecology, 2016Co-Authors: Laia Alegret, Silvia Ortiz, Gabriela J Arreguinrodriguez, Simonetta Monechi, Isabel Millan, Eustoquio MolinaAbstract:Abstract The Latest Danian Event (LDE) or Top Chron C27n hyperthermal event has been identified in the Caravaca section (Southern Spain) by means of calcareous nannofossil biozones (Subzone NTp7b) and the recognition of a prominent, negative ~ 0.6 per mille carbon isotope excursion measured in benthic foraminiferal tests. This is the first time that this Danian hyperthermal event has been identified in a deep-water, middle to lower bathyal setting from the Western Tethyan realm. The analysis of benthic foraminiferal assemblages shows gradual changes in the assemblages prior to the onset of the LDE and an increase in food supply to the seafloor during the LDE, in agreement with results from shallower Southern Tethyan settings. The benthic assemblage changes across the LDE at Caravaca share some characteristics with other hyperthermal events, including the negative carbon isotope excursion, the increased abundance of buliminids, or the common occurrence of A. aragonensis, an opportunistic species that proliferated during other Paleogene hyperthermal events. In addition, the increased abundance of Nuttallides truempyi, a dissolution-resistant form that thrived during the Paleocene Eocene Thermal Maximum, and the abundance of calcareous infaunal morphogroups, which calcify in less carbonate-undersaturated pore waters, indicate slightly CaCO3-corrosive bottom waters during the LDE. Turnover of calcareous plankton across the LDE is similar to other sites globally distributed, including the evolution of photosymbiotic foraminiferal lineages and the radiation of the nannofossil “fasciculiths group”. The occurrence of innovative morphostructures (Diantholitha and Lithoptychius) towards the base of the LDE may indicate a more efficient biological pump. This hypothesis is supported by increased percentages of benthic infaunal morphogroups and a decrease in the abundance of oligotrophic species. A reworked interval has been identified immediately above the LDE. Higher up in the section, benthic and planktic assemblages from the post-LDE interval point to the recovery of the environmental conditions, including a decrease in the food supply to the seafloor.
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foraminiferal and δ13c isotopic event stratigraphy across the Danian selandian transition at zumaya northern spain chronostratigraphic implications
Terra Nova, 2008Co-Authors: Ignacio Arenillas, Eustoquio Molina, Silvia Ortiz, Birger SchmitzAbstract:unconformity, characterized by a ma- jor lithological shift from greyish white, oxic limestone ⁄ chalk of the Danskekalk Fm., upper Danian, to suboxic, glauconitic green sand of the Lellinge Greensand Fm., lower Selan- dian, overlain by grey marl and clay of the Kerteminde Marl Fm., middle Selandian. This unconformity was correlated with the sequence bound- ary between cycles TA 1.3 and TA 1.4 ABSTRACT The Zumaya section, northern Spain, is a suitable candidate to define the Global Stratotype Section and Point for the base of the Selandian Stage (Palaeocene) because of its excellent accessibility, exposure and stratigraphic continuity. Uncertain- ties exist, however, with regard to the stratigraphic horizon where to place the Danian ⁄ Selandian (D ⁄ S) boundary. Five potential stratigraphic horizons (HDS1 to HDS5) to define the D ⁄ S boundary have been identified at Zumaya, based on integrated stratigraphic studies that include quantitative plank- tic and benthic foraminiferal results, as well as d 13 C isotopic and lithological data. Two of these horizons (HDS2 and HDS4) placed in Zone C26r appear to have particularly good potential for serving as the D ⁄ S boundary marker, because they may represent significant global palaeoceanographic, palaeoclimatic and eustatic events.
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analisis de las asociaciones de foraminiferos del transito daniense selandiense en caravaca murcia foraminiferal assemblages analysis ofthe Danian selandian transition at caravaca murcia
2008Co-Authors: Silvia Ortiz, Laia Alegret, Eustoquio MolinaAbstract:The benthic and planktic foraminiferal assemblages tumover has been analysed in the Caravaca section (Murcia) in arder to recognize the Danian/Selandian boundary (DIS). The boundary stratotype of the base of the Selandian Stage has been recently defined in Zumaya (Guipuzcoa) in coincidence with a prominent lithological change and the second evolutionary radiation of the calcareous nannofissil Fasciculithus recognizable throughout the Danian-Selandian transition. lt is clase to the calcareous nannofossil zanal boundary NP4/NP5 anda shift in d 3 C. Five distinct horizons have been identified in Zumaya based on micropaleontological and isotopic data, four of which have been observed in Caravaca. One of these events seems to correspond with a paleoclimatic hyperthermal event and it correlates to the DIS boundary in Zumaya.
