Global paleobiogeography of Albian—Cenomanian(mid-Cretaceous)marine ostracods  

作　　者：Bernardo Vázquez-García Jorge Villegas-Martín Gerson Fauth Leonardo Borghi Aristóteles De Moraes Rios Netto 

机构地区：[1]Post-Graduate Program in Geology,Unisinos University,Sao Leopoldo,RS,Brazil [2]Technological Institute of Paleoceanography and Climate Change-Itt Oceaneon,Unisinos University,Sao Leopoldo,RS,Brazil [3]Laboratory of Sedimentary Geology(Lagesed),Department of Geology,Institute of Geosciences,UFRJ-Federal Universityof Riode Janeiro,Brazil [4]Labmicro,Department of Geology,Institute of Geosciences,UFRJ-Federal University of Rio de Janeiro,Brazil

出　　处：《Journal of Palaeogeography》2024年第2期212-236,共25页古地理学报（英文版）

基　　金：developed in association with the R&D project registered as Brazilian National Agency of Petroleum,Natural Gas and Biofuels—ANP 18993—6(SACL—Sedimentary geological analysis of Cretaceous carbonate successions in a Brazilian Sedimentary Basin);financial support from PETROBRAS 2023/00305—8(PALEOCLIMA project—Paleoclimatic evolution and paleobathymetry of the Southern Hemisphere during the Jurassic(Tithonian)and Cretaceous)。

摘　　要：Despite their potential for providing important information for paleobiogeography,studies using ostracod assemblages compiled from global datasets have been scarce so far.In this study,the paleogeographic implications of the relationship between different ostracod assemblages are analyzed and discussed for the Albian and Cenomanian.We compiled an ostracod dataset at the genus level,with 168 genera for the Albian and 174 for the Cenomanian,to which different multivariate statistical methods of grouping were applied.The affinity between different ostracod assemblages from different regions allowed for the delineation of 30 operational geographic units(OGUs)for the Albian,and 32 OGUs for the Cenomanian,grouped in three paleobiogeographic units(PBUs;Megatethys,Persia,and Austral)and one sub-unit(PBSU;Maghreb associated to the Megatethys).The Maghreb PBSU showed minor changes between the Albian and Cenomanian.The relationship among the OGUs grouped in each PBU is related to different factors,such as eustatic sea level events,similar climatic zones,and marine current circulation patterns.A relationship was observed between the Gabon and Nigeria OGUs with the Persia PBU,which suggests a direct east—west connection between them during the Cenomanian.The affinity observed in the Austral PBU between the South American,South African,and Australian regions during the Albian can be explained by their relative geographic isolation due to the Walvis Ridge barrier.The eventual flooding of this barrier led to the relationship observed between the SE Brazilian and Bolivian regions with the Austral PBU.Finally,the data also suggested that the separation of the Indian subcontinent from the Austral PBU took place during the Cenomanian.

关 键 词：Operational geographic units Paleobiogeographic units ALBIAN CENOMANIAN Marine ostracods 

分 类 号：Q915[天文地球—古生物学与地层学] P736.22[生物学—古生物学] P534.53