Timing of the Permian–Triassic biotic crisis: implications from new zircon U/Pb age data (and their limitations)

High-precision timeline for Earth’s most severe extinction

“…Since 1998, four major U-Pb geochronological studies have attempted to constrain the timing and duration of the extinction (3,(13)(14)(15). To better understand the relationship between environmental perturbation and biotic response, accurate and precise age models that integrate geochronology, paleontology, and geochemistry must be developed (8,11,16,17).…”

“…Recognition of astronomically forced sedimentary cycles (Milankovitch cycles) in late Permian and Triassic sedimentary rocks tuned with available geochronology have been used to refine existing age models of the biotic crisis (18)(19)(20). Published estimates of the extinction interval based on radioisotopic dates range from ∼1.5 Mya to approximately <200 ± 100 ka, whereas astrochronological interpretations range from ∼700 ka to as little as ∼10 ka (3,14,15,18,19). Most recently, Wu et al (20) used Milankovitch cyclicity and previously published geochronology to constrain the maximum extinction interval at Meishan to 83 ka.…”

Triggers of Permo-Triassic boundary mass extinction in South China: The Siberian Traps or Paleo-Tethys ignimbrite flare-up?

“…2). These ash layers have been extensively studied in the past 30 years (e.g., Bowring et al, 1998;Clark et al, 1986;Metcalfe et al, 1999;Mundil et al, 2001Mundil et al, , 2004Shen et al, 2011Shen et al, , 2012Shen et al, , 2013Zhou and Kyte, 1988). It is widely accepted that the PTB volcanic ash layers may have been deposited during the latest Permian and the earliest Triassic, and that they are felsic in composition and may have been formed in a subduction-related setting (Clark et al, 1986;Gao et al, 2013;Isozaki et al, 2007;Shen et al, 2012;Yang et al, 2012;Yin et al, 2007;Zhou and Kyte, 1988).…”

High‐resolution Lopingian (Late Permian) timescale of South China

“…Fusulinids are from Jin et al (1999). Geochronologic ages are from our latest data, Bowring et al (1998), Mundil et al (2001Mundil et al ( , 2004, Zhou et al (2002) and Zhong and Zhu (2006). Polarity zones are from Jin et al (2000b); Chen et al (1991); Glen et al (2009);Heller et al (1988Heller et al ( , 1995; Steiner et al (1989Steiner et al ( , 2006, Li and Wang (1989) and Liu et al (1999).…”

“…The Lopingian geochronologic timescale has been greatly improved by dating a series of ash beds from the Meishan and Shangsi sections in South China (Bowring et al, 1998;Mundil et al, 2001Mundil et al, , 2004. A SHRIMP age of 251.2 AE 3.…”