Low oxygen levels in earliest Triassic soils

  title={Low oxygen levels in earliest Triassic soils},
  author={Nathan D. Sheldon and Gregory J. Retallack},
An earliest Triassic methane postapocalyptic greenhouse following the Permian-Triassic (P-T) extinction event was proposed on the basis of evidence of deeply weathered paleosols at high latitudes with features of low-latitude soils, and low stomatal index values of seed fern leaves. Reexamination of distinctive phyllosilicates, unique to a single stratigraphic level, in paleosols located just above the isotopically defined Permian-Triassic boundary in Australia and Antarctica furnishes… 

Figures from this paper


The presence of fusain (fossil charcoal) in sedimentary rocks is widely regarded as evidence of paleowildfire, and an apparent scarcity of fusain in strata of Triassic age has been cited as evidence

Abrupt chemical weathering increase across the Permian-Triassic boundary

The Permian–Triassic boundary in Antarctica

The Permian ended with the largest of known mass extinctions in the history of life. This signal event has been difficult to recognize in Antarctic non-marine rocks, because the boundary with the

Early geochemical environment of Mars as determined from thermodynamics of phyllosilicates

The results show that Fe3+-rich phyllosilicates probably precipitated under weakly acidic to alkaline pH, an environment different from that of the following period, which was dominated by strongly acid weathering that led to the sulphate deposits identified on Mars.

Permian greenhouse crises

Long records of paleosols from Australia, South Africa and Texas-Oklahoma now reveal abrupt and transient peaks of warm-wet paleoclimate at key biostratigraphic turning points of the end-Kungurian,

Return to Coalsack Bluff and the Permian–Triassic boundary in Antarctica

Vertebrate extinction across Permian–Triassic boundary in Karoo Basin, South Africa

Distinct assemblages of paleosols above and below the Permian–Triassic boundary in the Karoo Basin of South Africa are evidence for reorganization of ecosystems following this greatest of all mass



Landscape ecological shift at the Permian‐Triassic boundary in Antarctica

Palaeosols across the Permian‐Triassic boundary in Antarctica provide evidence of a marked change in ecosystems at this greatest of all extinctions in the history of life on Earth. The boundary can

Postapocalyptic greenhouse paleoclimate revealed by earliest Triassic paleosols in the Sydney Basin, Australia

The Permian-Triassic boundary in the Sydney Basin of Australia is coincident with a pronounced decrease in δ 13 C isotopic values of organic carbon, the last coals anywhere in the world for all of

δ13C depth profiles from paleosols across the Permian-Triassic boundary: Evidence for methane release

Stable carbon isotopic analyses of organic carbon (δ 13 C) in individual paleosol profiles from Permian–Triassic sequences of Antarctica reveal systematic isotopic variations with profile depth.

Global coal gap between Permian-Triassic extinction and Middle Triassic recovery of peat-forming plants

Early Triassic coals are unknown, and Middle Triassic coals are rare and thin. The Early Triassic coal gap began with extinction of peat-forming plants at the end of the Permian (ca. 250 Ma), with no

δ13Corg chemostratigraphy of the Permian‐Triassic boundary in the Maitai Group, New Zealand: Evidence for high‐latitudinal methane release

Abstract Carbon isotopic studies from marine organic matter of the Permian‐Triassic Maitai Group, New Zealand, reveal a significant δ13Corg shift toward more negative values within the Little Ben

Permian-Triassic extinction: Organic δ13C evidence from British Columbia, Canada

The Permian-Triassic (P-T) extinction is documented geochemically in a marine sequence deposited in a basinal setting at Williston Lake, northeastern British Columbia, by using elemental and isotopic

The Source and Fate of Massive Carbon Input During the Latest Paleocene Thermal Maximum.

The deposition of a mud clast interval and seismic evidence for slope disturbance provide evidence to confirm the gas hydrate dissociation hypothesis and identify the Blake Nose as a site of methane release.

Berthierine from the non-marine Wealden (Early Cretaceous) sediments of south-east England

  • K. Taylor
  • Environmental Science, Geography
    Clay Minerals
  • 1990
Abstract A thin (15–20 cm) Fe-rich intraformational conglomerate in the fresh- to brackish-water Early Cretaceous succession of south-east England contains pisoids and pseudo-ooids of a green clay

Examination of hypotheses for the Permo–Triassic boundary extinction by carbon cycle modeling

  • R. Berner
  • Environmental Science
    Proceedings of the National Academy of Sciences of the United States of America
  • 2002
Modeling indicates that measured short-term changes in δ13C at the boundary are best explained by methane release with mass mortality and volcanic degassing contributing in secondary roles, which results in excessively high levels of atmospheric CO2 if they occurred on time scales of more than about 1,000 years.

Ocean stagnation and end-Permian anoxia

Ocean stagnation has been invoked to explain the widespread occurrence of organic-carbon–rich, laminated sediments interpreted to have been deposited under anoxic bottom waters at the time of the