Paul B Wignall

University of Leeds · School of Earth and Environment

Phosphorus is generally considered the ultimate limiting nutrient for marine primary productivity over geological timescales and plays a key role in modulating several biogeochemical cycles. Most established methods for investigating P cycling do not provide direct evidence for water-column P concentrations, but recent work on carbonate associated...

The marine losses during the Permo-Triassic mass extinction were the worst ever experienced. All groups were badly affected, especially amongst the benthos (e.g. brachiopods, corals, bryozoans, foraminifers, ostracods). Planktonic populations underwent a fundamental change with eukaryotic algae being replaced by nitrogen-fixing bacteria, green-sulp...

Significance The Carnian Stage of the Triassic Period marks one of the most significant intervals of the past 250 My. Within the space of ∼2 My, the world’s biota underwent major changes with dinosaurs becoming the notable incumbents. These events coincide with a remarkable interval of intense rainfall known as the Carnian Pluvial Episode (CPE). He...

Teratological spores and pollen are widespread in sediments that record the Permian- Triassic mass extinction. The malformations are thought to be the result of extreme environmental conditions at that time, but the mutagenic agents and the precise timing of the events remain unclear. We examined the abundance of teratological sporomorphs and metal...

The role of ocean anoxia as a cause of the end-Triassic marine mass extinction is widely debated. Here, we present carbonate-associated sulfate d34S data from sections spanning the Late Triassic–Early Jurassic transition, which document synchronous large positive excursions on a global scale occurring in ~50 thousand years. Biogeochemical modeling...

The decline in species richness from the equator to the poles is referred to as the latitudinal diversity gradient (LDG). Higher equatorial diversity has been recognised for over 200 years, but the consistency of this pattern in deep time remains uncertain. Examination of spatial biodiversity patterns in the past across different global climate reg...

Significance The deep-time dynamics of the latitudinal diversity gradient (LDG), especially through dramatic events like mass extinctions, can provide invaluable insights into the biotic responses to global changes, yet they remain largely underexplored. Our study shows that the shape of marine LDGs changed substantially and rapidly during the Perm...

The foreshore at Redcar hosts the oldest Jurassic succession exposed on the Yorkshire-Cleveland Coast but has received little attention since the late nineteenth century. Temporary removal of beach sands by winter storms early in 2018 allowed for a sedimentological and palaeontological study of a nearly 60 m-thick foreshore section. The rocks are l...

EDITORIAL: The special volume of 'Global and Planetary Change' is dedicated to studies of 'Devonian global changes'. The 12 articles add much data to our knowledge of this eventful Middle Palaeozoic interval. In particular, the diversity of elemental and C-isotope geochemical signatures of two major biotic crises: the Frasnian-Famennian and Devonia...

Large Igneous Province eruptions coincide with many major Phanerozoic mass extinctions, suggesting a cause-effect relationship where volcanic degassing triggers global climatic changes. In order to fully understand this relationship, it is necessary to constrain the quantity and type of degassed magmatic volatiles, and to determine the depth of the...

The Permian-Triassic mass extinction is widely attributed to the global environmental changes caused by the eruption of the Siberian Traps. However, the precise temporal link between marine and terrestrial crises and volcanism is unclear. Here, we report anomalously high mercury (Hg) concentrations in terrestrial strata from southwestern China, syn...

Reefs are an excellent tool for tracking marine-ecosystem changes, especially through mass extinction transitions. Although metazoan reefs proliferated during the Phanerozoic, prolonged metazoan reef-recovery intervals often occurred after extinction events. Here, we document and review the reef-recovery interval following the Late Devonian Frasnia...

Mass extinctions are global-scale environmental crises marked by the loss of numerous species from all habitats. They often coincide with rapid changes in the stable carbon isotope ratios (13C/12C) recorded in sedimentary carbonate and organic matter, ratios which can indicate substantial inputs to the surface carbon reservoirs and/or changes in th...

Extinction has occurred throughout the history of life, with the result that nearly all the species that have ever existed are now extinct. Extinction: A Very Short Introduction looks at the causes and nature of extinctions, past and present, and the factors that can make a species vulnerable. Summarizing what we know about all of the major and min...

What is a mass extinction? Mass extinction events are geologically short intervals of time (always under a million years), marked by dramatic increases of extinction rates in a broad range of environments around the world. In essence they are global catastrophes that left no environment unaffected and that have fundamentally changed the trajectory...

Despite the less-than-perfect nature of the fossil record, it still provides a unique window on the history of life, and reveals that there have been dramatic fluctuations in extinction intensities since complex life evolved around 600 million years ago. ‘Extinction in the past’ considers Jack Sepkoski’s database compiled in the 1980s, and his seri...

The fossil record shows that life has experienced five major mass extinctions. A sixth catastrophe may be underway. Past mass extinctions were geologically short-lived intense crises that affected animals and plants in all environments. They removed the dominant and abundant species, leaving ecological voids to be filled by groups that were often r...

The Ice Age or Pleistocene Period, from 2.6 million to 11,650 years ago, was a time when the climate cycled from glacial to interglacial states every 100,000 years or so, resulting in significant sea-level changes. During the last glacial maximum, numerous large, terrestrial animals disappeared, now termed the Pleistocene megafauna extinction. Its...

‘Why extinctions happen’ looks at what we currently know about causes and styles of extinction today and in the past. This knowledge lies at the heart of our understanding about the way the Earth’s environment works and what happens at times of extremes. The importance of the species–area relationship is discussed and it is shown that species with...

‘How to kill nearly everything’ considers the proposed causes of mass extinctions, often called the kill mechanisms. An almost bewildering array of ideas have been put forward as likely bringers of death, but most of the debates have concentrated on just a few culprits, notably volcanism and meteorite impact, because their timing is closely coincid...

Oxygen restricted conditions were widespread in European shelf seas after the end-Triassic mass extinction event and they are reported to have hindered the recovery of marine benthos. Here we reconstruct the redox history of the Early Jurassic Blue Lias Formation of southwest Britain using pyrite framboid size analysis and compare this with the rec...

Ocean temperature and dissolved oxygen concentrations are critical factors that control ocean productivity, carbon and nutrient cycles, and marine habitat. However,the evolution of these two factors in the geologic past are still unclear. Here, we use a new oxygen isotope database to establish the sea surfacetemperature(SST) curve in the past 500 m...

The Capitanian (Guadalupian) witnessed one of the major crises of the Phanerozoic and, like many other extinctions, it coincided with the eruption of a large igneous province, in this case the Emeishan Traps of SW China. However, the timing and causal relationships of this event are in dispute. This study concentrates on the deep-water chert-mudsto...

Flood basalt volcanism represented by the Kalkarindji Province(Australia) is temporally associated with a trilobite mass extinction at the Cambrian Series 2 – Series 3 boundary, providing one of the oldest potential links between volcanism and biotic crisis in the Phanerozoic. However, the relative timing of flood basalt volcanism (Kalkarindji Prov...

A major extinction pulse occurred just below the conodont‐defined Permian‐Triassic boundary. Global‐scale compilations of increasingly larger paleontological, sedimentological, and geochemical datasets further amplify our understanding of this event by unraveling temporospatial patterns. Robust stratigraphic frameworks are an integral part of these...

With the aim to understand prolonged and repeated marine anoxia after the Triassic-Jurassic mass- extinction event, a continuously cored, 338 metre thick succession of Rhaetian to Toarcian sediments was retrieved close to the village of Schandelah near Braunschweig (Lower Saxony, northern Germany). Here, preliminary biostratigraphical, lithological...

Life on Earth suffered its greatest bio-crisis since multicellular organisms rose 600 million years ago during the end-Permian mass extinction. Coincidence of the mass extinction with flood basalt eruptions in Siberia is well established, but the exact causal connection between the eruptions and extinction processes in South China is uncertain due...

Lithofacies analysis, optical microscopic and X-ray diffraction approaches were employed to investigate basin-fill configuration and palaeodepositional environments of the Mamfe Cretaceous Basin in SW Cameroon. The asymmetric basin-fill comprises six lithofacies associations whose vertical architectures are influenced by early syn-rift, mid syn-rif...

Guadalupian organic-rich depositions within the eastern Paleo-Tethys Margin have been attributed to coastal upwelling, but the idea has not been tested. Here, a suite of geochemical proxies from the Gufeng Formation of the Lower Yangtze region (South China) are used to investigate the formation mechanisms of organic matter accumulation. A high orga...

The enigmatic biotic and environmental changes during the Carnian Humid Episode (CHE) have been investigated in South China. The body size of conodonts, assessed as length of P1 elements, and their diversity show substantial changes in the mid-Carnian. The well-dated Long Chang, Yongyue and Caizitang sections in southwestern China record a change o...

The Frasnian-Famennian (F-F) global event, one of the five largest biotic crises of the Phanerozoic, has been inconclusively linked to rapid climatic perturbations promoted in turn by volcanic cataclysm, especially in the Viluy large igneous province (LIP) of Siberia. Conversely, the triggers of four other Phanerozoic mass extinction intervals have...

A negative shift in the calcium isotopic composition of marine carbonate rocks spanning the end-Permian extinction horizon in South China has been used to argue for an ocean acidification event coincident with mass extinction. This interpretation has proven controversial, both because the excursion has not been demonstrated across multiple, widely...

Macrofauna is known to inhabit the top few 10s cm of marine sediments, with rare burrows up to two metres below the seabed. Here, we provide evidence from deep-water Permian strata for a previously unrecognised habitat up to at least 8 metres below the sediment-water interface. Infaunal organisms exploited networks of forcibly injected sand below t...

The measurement of isotope ratios in sedimentary rocks deposited over geological time can 6 provide key insights to past environmental change over important intervals in the past. However, it is 7 important to be aware that secondary alteration can overprint the original isotopic records. We demonstrate 8 this principle using high-resolution carbon...

The measurement of isotope ratios in sedimentary rocks deposited over geological time can provide key insights to past environmental change over important intervals in the past. However, it is important to be aware that secondary alteration can overprint the original isotopic records. We demonstrate this principle using high-resolution carbon, sulf...

Banded iron formations were a prevalent feature of marine sedimentation ~3.8–1.8 billion years ago and they provide key evidence for ferruginous oceans. The disappearance of banded iron formations at ~1.8 billion years ago was traditionally taken as evidence for the demise of ferruginous oceans, but recent geochemical studies show that ferruginous...

Bulk-carbonate carbon isotope ratios are a widely applied proxy for investigating the ancient biogeochemical carbon cycle. Temporal carbon isotope trends serve as a prime stratigraphic tool, with the inherent assumption that bulk micritic carbonate rock is a faithful geochemical recorder of the isotopic composition of seawater dissolved inorganic c...

The recognition of a long-term negative carbon isotope trend straddling the Permian-Triassic boundary beds is widely accepted 1,2. Equally important is the notion that superimposed second-order scatter marks this geochemical record, hindering high-resolution intra-and inter-basinal correlation attempts 1,2. A more in-depth understanding of the natu...

Bulk-carbonate carbon isotope measurements are a widely applied proxy for investigating the ancient biogeochemical carbon cycle. Temporal carbon isotope trends serve as a prime stratigraphic tool, with the inherent assumption that bulk micritic carbonate rock is a faithful geochemical recorder of the isotopic composition of seawater dissolved inorg...

We thank Davies et al. (2017) for their comments and welcome the opportunity to further discuss the role of early land plants in fluvial environments. Critically, Davies et al. (2017) note that although testable hypotheses exist for the possible role of early land plants they remain untested, and thus there is correlation (between an increase in me...

Bulk-carbonate stable carbon isotope records are used to proxy the ancient biogeochemical carbon cycle as well as aid in determining the age of sedimentary deposits. However, the multicomponent nature and the component-specific diagenetic potential of bulk-rock pose limits on the applicability of this proxy in recording ancient seawater chemistry a...

The mass extinction of the olenellid trilobites occurred around the Cambrian Series 2-Series 3 boundary. Like many other crises, it coincided with a negative carbon isotope excursion but the associated palaeoenvironmental changes remain unclear. To investigate the causal mechanism for this event, we report facies changes, pyrite framboid petrograph...

The Cambrian Series 2- 3 boundary marks the first mass extinction of the Phanerozoic and, like many other extinction intervals, coincides with a negative inorganic carbon isotope excursion (ROECE) and the eruption of a large igneous province (Kalkarindji LIP). In the western Great Basin (USA) the extinction of the olenellid trilobites lies within a...

The subdivision of Ladinian and Carnian strata in Guizhou, South China has been a matter of intense debate because of the paucity of age-diagnostic faunas. Here we have carried out a detailed conodont biostratigraphic investigation on the Yangliujing, Zhuganpo and Wayao formations in the Yongyue section of western Guizhou Province. Conodonts are on...

Based on seven measured sections from Svalbard, the marine strata of the Permian Kapp Starostin Formation are arranged into seven transgressive–regressive sequences (TR1–TR7) of c . 4–5 Ma average duration, each bound by a maximum regressive surface. Facies, including heterozoan-dominated limestones, spiculitic cherts, sandstones, siltstones and sh...

Permian strata from the Tieqiao section (Jiangnan Basin, South China) contain several distinctive conodont assemblages. Early Permian (Cisuralian) assemblages are dominated by the genera Sweetognathus, Pseudosweetognathus and Hindeodus with rare Neostreptognathodus and Gullodus. Gondolellids are absent until the end of the Kungurian stage—in contra...

Globally, the Series 2 – Series 3 boundary of the Cambrian System coincides with a major carbon isotope excursion, sea-level changes and trilobite extinctions. Here we examine the sedimentology, sequence stratigraphy and carbon isotope record of this interval in the Cambrian strata (Durness Group) of NW Scotland. Carbonate carbon isotope data from...

A detailed, 10 m.y. redox history of Changhsingian to Anisian (latest Permian to Middle Triassic) oceans in ramp settings is reconstructed based on framboidal pyrite analysis from South China. The result shows that the well-established phenomenon of intense ocean euxinia-anoxia is faithfully recorded in pyrite framboid data. Three major euxinia-ano...

The Carnian Humid Episode (CHE), also known as the Carnian Pluvial Event, and associated biotic changes are major enigmas of the Mesozoic record in western Tethys. We show that the CHE also occurred in eastern Tethys (South China), suggestive of a much more widespread and probably global climate perturbation. Oxygen isotope records from conodont ap...

Debate continues about the nature of the Cretaceous–Paleogene (K–Pg) mass extinction event. An abrupt crisis triggered by a bolide impact contrasts with ideas of a more gradual extinction involving flood volcanism or climatic changes. Evidence from high latitudes has also been used to suggest that the severity of the extinction decreased from low l...

The outcrops of the Shannon region provide some of the best Carboniferous sections to be seen in north-west Europe. Basin style is an especially contentious issue and several conflicting, and to some extent irreconcilable, models have been proposed. This chapter highlights the key attributes of the various competing depositional models that have be...

The Clare Shale Formation is a manifestation of a widespread phase of black shale deposition seen in the mid-Carboniferous basins of NW Europe. This chapter describes localities that are widely separated and the visits to the Clare Shale sites with nearer-at-hand localities. It introduces the outcrop near Lisdoonvarna in northern County Clare. The...

This chapter presents an introduction to the field guide that provides a detailed account of the Carboniferous geology of the Shannon Basin, principally in County Clare and County Kerry, Western Ireland. This guide provides a summary of both past work and ongoing debate on the interpretation of the exceptional outcrops, through description of the p...

The Tullig Cyclothem marks the first and thickest of the repeated cyclical pulses of sedimentation that filled the Shannon Basin after deposition of the Gull Island Formation, with a total of five such deltaic cycles being seen in County Clare. This chapter discusses several excursions to key localities of the Tullig and Kilkee Cyclothems in southe...

The extensive coastal exposures along the south-facing shore of Liscannor Bay and the spectacular, giant cliffs that stretch from Hag's Head to the Cliffs of Moher provide a series of superb exposures of the northern-most outcrops of the Tullig and Kilkee cyclothems in County Clare. The Cliffs of Moher are one of the main tourist sites in Ireland b...

The Carboniferous rocks of County Clare are arranged into a broad syncline, with the result that the coastal outcrops in the central part of the County expose the youngest strata of the region, three deltaic cyclothems, namely the Tullig, Kilkee and Doonlicky cyclothems, and the unnamed cyclothems IV and V. This chapter focuses on the younger Namur...

Progradational fluvio-deltaic systems tend towards but cannot reach equilibrium, a state in which the longitudinal profile does not change shape and all sediment is bypassed beyond the shoreline. They cannot reach equilibrium because progradation of the shoreline requires aggradation along the longitudinal profile. Therefore progradation provides a...

This thematic volume arose from a desire to acknowledge the pioneering contributions to mass extinction studies made by Professor Tony Hallam over the past 50 years and includes papers from several theme sessions held at the annual meeting of the Geological Society of America held in Denver in October 2013 along with other solicited contributions....

Several biotic crises during the past 300 million years have been linked to episodes of continental flood basalt volcanism, and in particular to the release of massive quantities of magmatic sulphur gas species. Flood basalt provinces were typically formed by numerous individual eruptions, each lasting years to decades. However, the environmental i...

New collecting at a biostratigraphically highly-resolved deep-water section in South China, reveals a brief (a few tens of thousands of years) but measurable delay in extinction timing relative to contemporaneous, shallower water sections. Foraminifers and conodonts in the Bianyang section show a sharp extinction at the top of Hindeodus changxingen...

The Cambrian Series 2/ Series 3 (early-middle Cambrian) transition is marked by major shifts in carbon isotopes values, the eruption of the Kalkarindji large igneous province in Australia, substantial sea-level oscillations and two extinction crises. However, the relative timing of all these phenomena is poorly understood – no single section or loc...

The end-Permian ( c. 252 Ma) and end-Triassic ( c. 201 Ma) mass-extinction events are commonly linked to the emplacement of the large igneous provinces of the Siberia Traps and Central Atlantic Magmatic Province, respectively. Accordingly, scenarios for both extinctions are increasingly convergent and cross-fertilization of ideas has become importa...

Lower Triassic marine strata in Spitsbergen accumulated on a mid-to-high latitude ramp in which high-energy foreshore and shoreface facies passed offshore into sheet sandstones of probable hyperpycnite origin. More distal facies include siltstones, shales and dolomitic limestones. Carbon isotope chemostratigraphy comparison allows improved age dati...

Survival and recovery are important dynamic processes of biotic evolution during major geological transitions. Disaster and opportunistic taxa are two significant groups that dominate the ecosystem in the aftermath of mass extinction events. Disaster taxa appear immediately after such crises whilst opportunists pre-date the crisis but also bloom in...