Global biostratigraphic comparison and correlation of an early Cisuralian palynoflora from Bolivia

Abstract

This paper presents new data about Early Permian (Cisuralian) strata, palynostratigraphy and absolute dating from the Copacabana Formation in central Bolivia. Recent stratigraphic and palynologic data from marine and transitional rocks at Apillapampa refine the age of Cisuralian palynomorphs in South America. Twelve samples interbedded with five volcanic ashes (processed and productive) yielded 94 palynomorph species arranged in two informal palynoassemblages: the lower assemblage Vittatina costabilis corresponds to one sample near the base of the Copacabana Formation and the upper Lueckisporites virkkiae assemblage occurs in overlying marine and coal-bearing transitional intervals. Ages were also independently refined by a modern review of conodonts, fusulinids, along with those U–Pb radiometric ages (Isotope Dilution Thermal Ionization Mass Spectrometry [ID-TIMS] of zircon-bearing interbedded tuffs). These data suggest that the lower marine member of the Copacabana Formation at this location is Asselian and Sakmarian. Lueckisporites virkkiae is a key species of palynomorph utilised in South American and global Permian biostratigraphic reconstructions. Hence, a thorough global comparison of these palynofloras and correlations is 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.

Keywords::

• Lueckisporites virkkiae
• palynostratigraphy
• correlations
• Cisuralian
• Copacabana Formation
• Bolivia

Acknowledgements

The authors thank the invaluable help of Shirley López (Sergeotecmin) and Shirley's husband Néstor Jiménez (UMSA) for their support and hospitality in La Paz, and Ramiro Suárez and Ricardo Céspedes at Museo de Historia Natural de Cochabamba. Finally, the authors also thank the geologists and people of Bolivia, to whom this geohistory is dedicated. Moreover, the Fulbright Commission and the CONICET are acknowledged for giving MdP the opportunity of keep on working in collaboration with Drs Peter Isaacson, George Grader and Heidi Anderson at the University of Idaho during 2009, and to PI with MdP at the CICYTTP in Diamante (Entre Ríos, Argentina) during 2011.

Supplementary material

Supplementary material can be accessed at http://dx.doi.org/10.1080/08912963.2014.910204

Notes

^1. Email: [email protected]

^2. Email: [email protected]

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^4. Email: [email protected]

^5. Email: [email protected]

Additional information

Funding

This work was financially supported from Projects CGL2006-07376/BTE (2007–2009, Enrique Díaz-Martínez) of the Spanish Government provided by the ‘Instituto Geológico y Minero de España’, projects 401769/2010-0, 402873/2012-2 and 480385/2010-6 and PQ 309211/2013-1 of the Brazilian Research Council (CNPq) given to Paulo A. Souza and Roberto Iannuzzi, respectively, project PqG 10/1584-6 of the Rio Grande do Sul State Research Council (FAPERGS) to Roberto Iannuzzi, and PIP 5518 (2005–2007) and PIP 0305 (2011–2013) of the ‘Consejo Nacional de Investigaciones Científicas y Técnicas’ (CONICET) and UBACYT X 428, 2008–2010 (University of Buenos Aires), to Mercedes di Pasquo.