Early Cisuralian palynoflora from Apillapampa, Bolivia: biostratigraphic significance

DI PASQUO, M.M.; GRADER, GEORGE; IANNUZZI, R.; ISAACSON, P.; SOUZA, PAULO ALVES; DIAZ-MARTINEZ, E.

Lisboa

Congreso; 1st INTERNATIONAL CONGRESS ON STRATIGRAPHY; 2013

Department of Earth Sciences and the Research Centre in Geological Science and Engineering, of the Faculty of Science and Technology, Universidade Nova de Lisboa (New University of Lisbon).

Recent stratigraphic and palynologic data from marine and transitional rocks of the Copacabana Formation at Apillapampa in central Bolivia refine the age of Cisuralian palynomorphs in South America. Samples interbedded with volcanic ashes yielded palynomorph taxa arranged in two informal palynoassemblages: the lower assemblage Vittatina costabilis (Vc) was collected from one sample at the base of the Copacabana Formation, and the upper Lueckisporites virkkiae (Lv) assemblage occurs in overlying marine and coal–bearing transitional intervals. Ages were also independently refined by a modern review of microfossil (conodonts and fusulinids) and five U-Pb radiometric ages (ID-TIMS of zircon-bearing interbedded tuffs) and confirmed that the Copacabana Formation at this location is Asselian and Sakmarian in age. Lueckisporites virkkiae and other palynomorphs are key species of palynozones utilized in South American and global Permian biostratigraphic reconstructions. Hence, a thorough global comparison of these palynofloras and correlations are addressed in this contribution considering first appearances of mainly cosmopolitan diagnostic taxa. Correlations are established with many similar Permian palynofloras, some also constrained with radiometric data, in South America (Brazil, Uruguay and Argentina) and elsewhere (Africa, Australia, Oman and Saudi Arabia). Key words: Lueckisporites virkkiae, Palynostratigraphy, Correlations, Cisuralian, Copacabana Formation, Bolivia.