Late Palaeozoic glacial cycles and subcycles in western Gondwana: Correlation of surface and subsurface data of the Paraná Basin, Brazil

Abstract

The Paraná Basin, the largest basin in South America, received glacially derived sediments during the Late Palaeozoic Ice Age (LPIA) of the Gondwana supercontinent.Despite the importance of this basin for understanding the continental development of the Gondwana glaciation, and the fact that ca. 95% of this basin is not exposed at the surface, few attempts have been made to connect the exposed glacial strata to the subsurface record. In this paper, exposures of glacial cycles in the Upper Itararé Group in Santa Catarina State, southern Brazil, are analyzed, locally correlated and then linked to the three major glacial cycles previously described from subsurface studies along the basin. Together study areas (Doutor Pedrinho and Vidal Ramos) record five, partially comparable shorter glacial subcycles (relative to the major glacial cycles). These series comprise coarse-grained subaqueous outwash deposits, turbidite sand sheets, marine shales, and diamictites, the latter mostly derived from delta slope failure and ensuing resedimentation. In addition to sedimentological and genetic stratigraphic description and analysis, preliminary age determination based on the palynological content is also presented. Besides, a regional correlation of the described succession to the subsurface record is proposed based on well logs and core information. All the palynomorph associations identified from the exposed successions, which represent the upper third part of the Itararé Group, are related to the Subzone Protohaploxypinus goraiensis, base of the Vittatina costabilis Zone. This zone and correlated ones along the Gondwana are considered Early Permian in age. However, a first isotopic age recently obtained for the upper Itararé Group and published elsewhere is considered within a regional stratigraphic framework once it leads to new insights in terms of the LPIA time span recorded in the Paraná Basin.

Exhumed subglacial landscape in Uruguay: Erosional landforms, depositional environments, and paleo-ice flow in the context of the late Paleozoic Gondwanan glaciation

“…The glacially abraded bedrock and the facies stacking composed of subglacial to proglacial deposits can be interpreted in terms of a glacial advance-retreat cycle similar to what have been described from other LPIA successions (e.g., Miller, 1989;França and Potter, 1991;Visser, 1997;Vesely and Assine, 2006;Vesely et al, 2015;Fallgatter and Paim, 2017;Valdez-Buso et al, 2017;Mottin et al, 2018). These deglaciation sequences record complete cycles of glacial advance and retreat either in terrestrial and marine environments and are often almost entirely composed of deposits accumulated during ice-margin retreat or deglaciation (Visser, 1997;Vesely and Assine, 2006).…”

Diversidade de estilos estruturais em depósitos de transporte em massa

“…Nos últimos anos, vários estudos têm abordado diversos aspectos dos MTDs do Grupo Itararé, tais como a geometria deposicional, relações de contato e potencialidade econômicas desses depósitos, fácies, modelo deposicional, características deformacionais, entre outros (e.g., Suss et al 2014, Carvalho & Vesely 2017, Valdez--Buso et al 2019, Mottin et al 2018, Schemiko et al 2019, Rodrigues et al 2020.…”

“…2A, 3A e 7A), e 3) diamictitos areno-argilosos (e.g., Fig. 3B, 6A e 8B) heterogêneos (matriz bandada) a homogêneos (matriz maciça) contendo grânulos a blocos intra-(arenito, folhelho, ritmito, e fragmentos de plantas) e extrabacinais (granitos e rochas metemórficas), alguns dos quais estriados e facetados (e.g., Vesely & Assine 2006, Suss et al 2014, Carvalho & Vesely 2017, Valdez-Buso et al 2019, Mottin et al 2018, Schemiko et al 2019, Rodrigues et al 2020.…”

“…No Grupo Itararé, unidade permocarbonífera da Bacia do Paraná, os MTDs são recorrentes e diversas estruturas de deformação têm sido documentadas (e.g., Rocha-Campos 1963;Salamuni et al 1966, Eyles et al 1993, Vesely et al 2005, Carneiro & Costa 2006, Vesely & Assine 2006, Suss et al 2014, Carvalho & Vesely 2017, Valdez-Buso et al 2019, Mottin et al 2018, Schemiko et al 2019, Rodrigues et al 2020. Contudo, não há ainda estudo sistemático de caracterização dessas estruturas.…”

Ice‐margin fluctuation sequences and grounding zone wedges: The record of the Late Palaeozoic Ice Age in the eastern Karoo Basin (Dwyka Group, South Africa)

“…These successive ice sheet waxing and waning events probably depended on parameters such as the wander of the South Pole (Opdyke et al, 2001), variable concentration of atmospheric CO 2 (Frank et al, 2008;Montañez et al, 2016;Myers, 2016), and/or the erection of mountain belts (Isbell et al, 2012;Goddéris et al, 2017). Investigations on correlative glaciogenic deposits across Gondwana have been carried out in South America (Dykstra et al, 2012;Vesely et al, 2015;Tedesco et al, 2016;Fallgatter and Paim, 2017;Valdez Buso et al, 2017;Assine et al, 2018), the Middle East (Martin et al, 2008;Stephenson et al, 2013), India (Wopfner and Jin, 2009), Madagascar (Wescott and Diggens, 1997), Australia (Fielding et al, 2008b), Antarctica (Isbell, 2010;Cornamusini et al, 2017) and North Africa (Le Heron et al, 2009;Bussert, 2010;, where spectacular, glacially related palaeoreliefs (fjords, ice stream corridors) have been discovered.…”