000061854 001__ 61854
000061854 005__ 20200221144348.0
000061854 0247_ $$2doi$$a10.1016/j.cretres.2015.10.11
000061854 0248_ $$2sideral$$a100088
000061854 037__ $$aART-2016-100088
000061854 041__ $$aeng
000061854 100__ $$aReolid, Matias
000061854 245__ $$aThe biotic crisis across the Oceanic Anoxic Event 2: Palaeoenvironmental inferences based on foraminifera and geochemical proxies from the South Iberian Paleomargin
000061854 260__ $$c2016
000061854 5060_ $$aAccess copy available to the general public$$fUnrestricted
000061854 5203_ $$aOpen marine sediments deposited during the CenomanianeTuronian transition are well exposed in the Spanish Ba~nos de la Hedionda section (Betic Cordillera, South Iberian Palaeomargin). Analysis of foraminiferal assemblages and geochemical proxies allow inferences on the impact of the Oceanic Anoxic Event 2 (OAE2) in this area of the western Tethys. Three main intervals have been identified corresponding to different lithological units and biozones. (1) The top of the Capas Blancas Member (Rotalipora cushmani Biozone) represents the pre-extinction phase with diverse foraminiferal assemblages and well developed water-column tiering, well-oxygenated, oligotrophic deep-waters and oxygenated to poorly oxygenated, mesotrophic surface-waters. Foraminiferal opportunist species point to a minor event with dysoxic conditions preceding the OAE2. (2) The black radiolaritic shales (Whiteinella archaeocretacea Biozone) consist of a foraminiferal-barren interval, except for the lowermost centimetres where planktic surface-dweller opportunists are common. Redox sensitive elements (Cr/Al, V/Al, U/Th, MoEF, Moaut, UEF and Uaut) and increased TOC values reflect oxygen depleted conditions related to the OAE2. The increase in P/Ti values at the base of this stratigraphic interval indicates an abrupt increase in productivity. High concentrations of radiolarians are congruent with high surface productivity probably related to changes in oceanic circulation and enhanced upwelling currents, as well as subsequent shallowing of the oxygenminimum zone. The increase in MoEF and Moaut towards the top of the black radiolaritic shales indicates temporal euxinic conditions. (3) A slow, bottom-up recovery of foraminiferal assemblages is inferred at the base of the Boqueron Member (Helvetoglobotruncana helvetica Biozone), with seafloor recolonization by benthic foraminifera being recorded previous to the water column colonization by planktic forms, mainly by intermediate-dwellers typical of mesotrophic waters. The subsequent proliferation of surfacedweller opportunists and deep-dweller opportunists adapted to mesotrophic to eutrophic conditions, and the decrease in planktic foraminiferal diversity, may indicate the persistence of poorly oxygenated conditions in the water column towards the lower-middle part of the H. helvetica Biozone.
000061854 536__ $$9info:eu-repo/grantAgreement/ES/DGA/E05$$9info:eu-repo/grantAgreement/ES/MICINN/RYC-2009-04316$$9info:eu-repo/grantAgreement/ES/MINECO/CGL2011-229121$$9info:eu-repo/grantAgreement/ES/MINECO/CGL2011-23077$$9info:eu-repo/grantAgreement/ES/MINECO/CGL2012-33281$$9info:eu-repo/grantAgreement/ES/MINECO-FEDER/CGL2014-58794-P
000061854 540__ $$9info:eu-repo/semantics/openAccess$$aby-nc-nd$$uhttp://creativecommons.org/licenses/by-nc-nd/3.0/es/
000061854 590__ $$a2.015$$b2016
000061854 591__ $$aPALEONTOLOGY$$b9 / 53 = 0.17$$c2016$$dQ1$$eT1
000061854 591__ $$aGEOLOGY$$b12 / 47 = 0.255$$c2016$$dQ2$$eT1
000061854 592__ $$a0.883$$b2016
000061854 593__ $$aPaleontology$$c2016$$dQ1
000061854 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/acceptedVersion
000061854 700__ $$aSánchez-Quiñónez, Carlos A.
000061854 700__ $$0(orcid)0000-0002-8801-9544$$aAlegret, Laia$$uUniversidad de Zaragoza
000061854 700__ $$0(orcid)0000-0001-5660-1428$$aMolina, Eustoquio$$uUniversidad de Zaragoza
000061854 7102_ $$12000$$2655$$aUniversidad de Zaragoza$$bDpto. Ciencias de la Tierra$$cÁrea Paleontología
000061854 773__ $$g60 (2016), 1-27$$pCretac. res.$$tCretaceous Research$$x0195-6671
000061854 8564_ $$s1007952$$uhttps://zaguan.unizar.es/record/61854/files/texto_completo.pdf$$yPreprint
000061854 8564_ $$s100522$$uhttps://zaguan.unizar.es/record/61854/files/texto_completo.jpg?subformat=icon$$xicon$$yPreprint
000061854 909CO $$ooai:zaguan.unizar.es:61854$$particulos$$pdriver
000061854 951__ $$a2020-02-21-13:53:55
000061854 980__ $$aARTICLE