Early Permian Palaeofloras From Southern Brazilian Gondwana: A Palaeoclimatic Approach

Abstract

In evaluating the parameters supplied by the taphofloras from different sedimentary facies in the Early Permian sedimentary sequences of the southern part of the Paraná basin, Brazil, it has become evident that the palaeofloristic evolution was related to palaeoecological and palaeoclimatic evolution. The homogeneous composition of Early Permian floral assemblages, which are characterized mainly by herbaceous to shrub-like plants considered to be relicts from the rigorous climate of an ice age (e.g. Botrychiopsis plantiana) suggest the persistence of the cold climate. The dominance of Rubidgea and Gangamopteris leaves with palmate venation associated with glossopterids with penate venation seems to indicate a gradual warming of climate. In roof-shales of coalbearing strata pinnate glossopterids related to Glossopteris are common, while Gangamopteris and Rubidgea (palmate forms) are poorly represented. The sudden enrichment of herbaceous articulates and filicoids fronds is characteristic of this stage and trunks of arborescents lycophytes become important elements. These antrocophilic paleofloras are characterized by typical elements of the "Glossopteris flora" associated to tree lycophytes and ferns communities. Therefore, the cool seasonal climate of Early Permian changed into the moist seasonal interval during the Artinskian-Kungurian. This climatic change was significant to the meso-hygrophitic to hygrophitic vegetation registered in roof-shale ferns of the Gondwana Southern Brazilian coalbearing strata.

Herbivoria em floras gonduânicas do Neopaleozóico do Rio Grande do Sul: análise quantitativa

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Paleoenvironments and age of the Talampaya Formation: The Permo-Triassic boundary in northwestern Argentina

“…These rocks were deposited in wide and very probably low gradient muddy alluvial plains in which low-to mediumsinuosity channels, which showed limited lateral migration, traversed. reported (Guerra-Sommer and Cazzulo-Klepziga, 2000;Holz et al, 2010;Limarino et al, 2014;Gulbranson et al, 2015). For example, the Paraná Basin shows a progressive trend to non-marine and more arid deposits from the Guadalupian to the Permian-Triassic boundary (Rhon et al, 2005;Holz et al, 2010;Limarino et al, 2014).…”

Evidências Paleobotânicas De Incêndios Vegetacionais No Afloramento Morro Papaléo, Paleozóico Superior Do Rio Grande Do Sul, Brasil.

“…De acordo com Guerra-Sommer & Cazzulo-Klepzig (2000b), com a retração das capas de gelo, a sedimentação glaciogênica do Subgrupo Itararé foi substituída por sistemas fluviodeltáicos e estuarinos da Formação Rio Bonito.…”