High-resolution δ13Ccarb chemostratigraphy from latest Guadalupian through earliest Triassic in South China and Iran

High-resolution SIMS oxygen isotope analysis on conodont apatite from South China and implications for the end-Permian mass extinction

“…At the Shangsi section, we can only infer that the cooling phase in the C. wangi zone is nearly synchronous with the positive return after the broad negative shift of 6.3‰ and smaller negative shift of 3.0‰ ( Fig. 5; Shen et al, 2013) due to absence of long-term δ…”

“…After thorough evaluation, the published conodont zones from Shangsi Shen et al, 2011Shen et al, , 2013, Daijiagou (Yuan et al, 2015), and Liangfengya (Yuan and Shen, 2011) were directly applied or accordingly modified as biostratigraphic constraints for intraregional correlations (Supplementary Tables S1-4). Several baselines for correlation were first established: (1) The PTB is at 42.11 m in Meishan, 100.4 m in Shangsi, 0.58 m in Daijiagou, and 0 m in Liangfengya, defined by the first appearances of Hindeodus parvus, except for Shangsi where the first occurrence of H. parvus was proven to be younger than many other occurrences including the FAD (First Appearance Datum) (Nicoll et al, 2002;Henderson, 2006;Jiang et al, 2011).…”

High-precision U-Pb CA-TIMS calibration of Middle Permian to Lower Triassic sequences, mass extinction and extreme climate-change in eastern Australian Gondwana

“…The end of the Middle Permian (end-Guadalupian) saw a profound sea-level fall, cooling event, and extinctions of low-latitude marine biota (Isozaki et al, 2007a(Isozaki et al, , 2007bWignall et al, 2009aWignall et al, , 2009b. Causative mechanisms are largely linked to the Emeishan Large Igneous Province volcanism (Shellnut et al, 2012), however the global nature of the end-Guadalupian mass extinction has been questioned (Rubidge et al, 2013;Shen et al, 2013). The greatest mass extinction of life on Earth occurred in the late Changhsingian (latest Permian) with the loss of ~85-90% of marine species (Jin et al, 2000;Shen et al, 2011) and ~60% of terrestrial families (Benton, 1995) over a short period of time, estimated at several hundred thousands of years or less Huang et al, 2011;Shen et al, 2011;Burgess et al, 2014).…”

“…Proposed killing mechanisms in the oceans include global anoxia associated with euxinia, hypercapnia (CO2 poisoning), ocean acidification, and extreme global warming. Kill mechanisms on land include increased CO2 and reduction of oxygen levels in the atmosphere (Schneebeli-Hermann et al, 2013), and injection of volcanic sulphate aerosols, and methane from clathrate reservoirs (Berner, 2002) with consequent global warming (Joachimski et al, 2012), aridity, wildfires, acid rain and mass wasting (Shen et al, 2013;Benton and Newall, 2014). Varied models have been proposed for the cause of the end-Permian extinction, and while hotly debated, the most widely accepted model identifies the consequences of the Siberian flood basalts as the principal cause.…”

Permian large igneous provinces: Characteristics, mineralization and paleo-environment effects

“…Yuan et al (2014) provides a new high-resolution conodont framework from the Meishan section in South China with a sample-population approach. They also established an integrative high-resolution framework including high-precision geochronologic ages (Burgess et al, 2014;Shen et al, 2011) and high-resolution chemostratigraphy (Cao et al, 2009;Shen et al, 2013) which provides a precise calibration for the largest mass extinction. Previously, numerous micropherules with various origins from asteroid impact and volcanism were reported from the PTB beds in South China.…”