Late Maastrichtian–Paleocene chronostratigraphy from Seymour Island,James Ross Basin,Antarctic Peninsula:Eustatic controls on sedimentation

作     者：Manuel MONTES Elisabet BEAMUD Francisco NOZAL Sergio SANTILLANA 

作者机构：Instituto Geológico y Minero de Espana(IGME)área de GeologíaGeomorfología y Cartografía GeológicaCalera 128760-Tres CantosMadridSpain Paleomagnetic Laboratory CCiTUB-Instituto de Ciencias de la Tierra'Jaume Almera’-CSICSole i Sabariss/n08028-BarcelonaSpain Instituto Antártico Argentino25 de Mayo 1143San Martínprovincia de Buenos AiresArgentina 

出 版 物：《Advances in Polar Science》 (极地科学进展（英文版）)

年 卷 期：2019年第30卷第3期

页      面：303-327页

核心收录：

学科分类：070903[理学-古生物学与地层学(含：古人类学)] 0709[理学-地质学] 07[理学] 

基　　金：supported by the Instituto Geológico y Minero de Espana (IGME) and Dirección General de Investigación (DGI) from Spain by the projects CTM2011-30241-C02-02 and CTM2014-60451-C2-2-P the Geomodels Research Institute and the Grup de Recerca de Geodinàmica i Anàlisi de Conques (Grant no. 2017SGR596, supported by AGAUR) 

主　　题：Paleocene magnetostratigraphy Antarctic Peninsula James Ross Basin Seymour Island 

摘      要：The Paleocene(66–56 Ma)was a critical time interval for understanding the geological history in high palaeolatitudes after the end of Cretaceous event(recovery from mass extinction,palaeoclimate,global sea level changes,among others).The sedimentary succession from Seymour Island(Antarctic Peninsula)provides key reference material from this important phase of the early Cenozoic.A detailed age model is proposed for the López de Bertodano Formation(LBF),Sobral Formation(SF)and Cross Valley–Wiman Formation(CVWF)based on a new magnetostratigraphic section which integrates previous dinoflagellate cyst biostratigraphy,Iridium anomaly(K-Pg boundary),U-Pb zircon dating(airfall tuff)and strontium isotope values from *** new composite magnetostratigraphic section,which includes the Cretaceous–Paleogene boundary,has been correlated to the GPTS from C29r up to *** top of the LBF is confirmed as latest Maastrichtian to earliest Danian(~65.4 Ma)in *** overlying SF is mostly Danian in age(~65.2–~63 Ma)and CVWF is Selandian–Thatenian(~61.3–56.9 Ma).LBF,SF and CVWF are unconformity-bounded units(alloformations)that record the geological evolution of the James Ross Basin during a period of relative decreasing tectonism but coeval with volcanic *** based internal units have been recognized,dividing each formation into allomembers(LBF:Molluscan and Cenozoic;SF:A,B and C;CVWF:Díaz,Ara?ado,Bahía Pingüino).The new age model allows correlation of base-level changes with eustatic sea-level *** bases of the SF and CVWF are correlated with the 65.3 and 61.5 Ma sea level lowstands.