Fluctuations of redox conditions across the Permian–Triassic boundary—New evidence from the GSSP section in Meishan of South China

Framboidal pyrite evidence for persistent low oxygen levels in shallow-marine facies of the Nanpanjiang Basin during the Permian-Triassic transition

“…compositions (e.g. Grice et al, 2005;Cao et al, 2009;Zhao and Tong, 2010;Chen et al, 2015;Li et al, 2016). Similar results, based on framboidal pyrites, were also noted from deeper facies sections, including Shangsi, Tianqiao, Changtanhe, Xiakou, Chaohu and Xiaojiaba ( Fig.…”

“…an oxygenation event immediately after the EPME, rather than an oxygen decline, especially in deeper settings, indicated by multiple proxies, including pyrite morphology, trace elements and biomarkers (Grice et al, 2005;Bond and Wignall, 2010;He et al, 2013;Wei et al, 2015a;Li et al, 2016;Kaiho et al, 2016). Further, Twitchett et al (2004) reported earliest Triassic invertebrate faunas from Oman that suggested good oxygenation of bottom waters in that region as well, against a backdrop of nearly universal anoxia in the earliest Triassic elsewhere.…”

“…Framboidal pyrites and sulfur isotopes have been widely used as indicators of euxinia and/or dysoxia in P-Tr redox studies (e.g. Wignall et al, 2005;Nielson and Shen, 2004;Gorjan et al, 2007;Algeo et al, 2008Algeo et al, , 2010Algeo et al, , 2011Bond and Wignall, 2010;Liao et al, 2010Liao et al, , 2017He et al, 2013;Dustira et al, 2013;Tian et al, 2014;Wang et al, 2015;Wei et al, 2015b;Li et al, 2016;Huang et al, 2017). We present the pyrite morphology and size distribution of pyrite framboids as well as sulfur isotope compositions of pyrites here to enable us to reconstruct the redox history of the Pingguo Platform and make wider palaeogeographic correlations.…”

Diverse earliest Triassic ostracod fauna of the non-microbialite-bearing shallow marine carbonates of the Yangou section, South China

“…Song et al (2014) proposed temporal 'refuge zone' variations from the latest Permian to Middle Triassic, showing a clear refuge zone expansion in the H. parvus Zone, as the potential dynamic for a diversified fauna (including ostracods) between the LPME and the ETME (Song et al 2013). Recent studies have suggested that there is little evidence for conditions favourable to metazoans in the H. parvus Zone, such as an oxygenation event (Bond & Wignall 2010;Loope et al 2013;Li et al 2016;Xiao et al 2018), paused temperature rise (Joachimski et al 2012) or moderate pH (Clarkson et al 2015).…”

Phanerozoic survivors: Actinopterygian evolution through the Permo‐Triassic and Triassic‐Jurassic mass extinction events

“…The Permo-Triassic mass extinction (PTME) is one of the best studied of all extinction events and has been linked to the eruptions of the Siberian Large Igneous Province resulting in massive climatic perturbations potentially analogous to modern anthropogenic climate change (Benton and Twitchett 2003;Kemp et al 2015). The PTME has been well dated to around 252 Ma (Mundil et al 2004;Li et al 2016;Liao et al 2016). The effects of the PTME on many invertebrate and vertebrate clades have been well documented, at least in terms of species richness (hereafter referred to simply as "diversity") with many showing dramatic declines across the Permian-Triassic boundary (PTB) (Jin et al 2000;Smith and Ward 2001;Retallack et al 2003;Benton et al 2004;Benton et al 2013;Song et al 2013).…”