A volcanic scenario for the Frasnian–Famennian major biotic crisis and other Late Devonian global changes: More answers than questions?

Global and Planetary Change, Journal Year: 2020, Volume and Issue: 189, P. 103174 - 103174

Published: March 20, 2020

Although the prime causation of Late Devonian Frasnian–Famennian (F–F) mass extinction remains conjectural, such destructive factors as spread anoxia and rapid upheavals in runaway greenhouse climate are generally accepted Earth-bound multicausal scenario. In terms triggers these global changes, volcanism paroxysm coupled with Eovariscan tectonism has been suspected for many years. However, recent discovery multiple anomalous mercury enrichments at worldwide scale provides a reliable factual basis proposing volcanic–tectonic scenario stepwise F–F ecological catastrophe, specifically Kellwasser (KW) Crisis. A focus is usually on cataclysmic emplacement Viluy large igneous province (LIP) eastern Siberia. long-lasted effusive outpouring was likely episodically paired amplified arc magmatism hydrothermal activity, oscillations glacioustatic responses could fact have promoted by diverse feedbacks driven tectonics. The anti-greenhouse effect expanding intertidal–estuarine riparian woodlands during transient CO2-greenhouse spikes another key feedback land. An updated volcanic press-pulse model proposed reference to timing LIPs revised date 371.9 Ma boundary. changes were initiated pre-KW activity LIPs, which caused extreme stress carbonate ecosystem. Nevertheless, least two decisive pulses sill-type intrusions and/or kimberlite/carbonatite eruptions, addition flood basalt extrusions East European Platform, thought eventually led end-Frasnian catastrophe. These stimuli enhanced effective orbital modulation. attractive option apply other events, evidences particular Hg that coincide end-Famennian Hangenberg

Language: Английский

---

Oceanic anoxic events, photic-zone euxinia, and controversy of sea-level fluctuations during the Middle-Late Devonian

Earth-Science Reviews, Journal Year: 2023, Volume and Issue: 241, P. 104415 - 104415

Published: April 10, 2023

Language: Английский

---

Periodic oceanic euxinia and terrestrial fluxes linked to astronomical forcing during the Late Devonian Frasnian–Famennian mass extinction

Earth and Planetary Science Letters, Journal Year: 2021, Volume and Issue: 562, P. 116839 - 116839

Published: March 2, 2021

Language: Английский

---

Global spatio-temporal variations and metallogenic diversity of karst bauxites and their tectonic, paleogeographic and paleoclimatic relationship with the Tethyan realm evolution

Earth-Science Reviews, Journal Year: 2022, Volume and Issue: 233, P. 104184 - 104184

Published: Sept. 12, 2022

Language: Английский

---

A synthesis of the Devonian wildfire record: Implications for paleogeography, fossil flora, and paleoclimate

Palaeogeography Palaeoclimatology Palaeoecology, Journal Year: 2021, Volume and Issue: 571, P. 110321 - 110321

Published: Feb. 24, 2021

Language: Английский

---

Bioclastic bottom‐current deposits of a Devonian contourite terrace: Facies variability and depositional architecture (Tafilalt Platform, Morocco)

Sedimentology, Journal Year: 2023, Volume and Issue: 70(5), P. 1413 - 1471

Published: Feb. 2, 2023

ABSTRACT The study examines bioclastic carbonate contourites that arise from the broad spectrum of bottom‐current related sedimentary processes ranging deposition to erosion. result intermittent accumulation sediment are thin and condensed successions with abundant hiatuses. Such deposits poorly known, since broadly accepted contourite‐facies model, bi‐gradational sequence, characterizes environments contourite depositional systems as a continuous accretion fine‐grained siliciclastic sediments. To increase current understanding facies within hiatal records, Eifelian–Frasnian Tafilalt Platform in Morocco was investigated. succession is divided into five associations interpreted reflect pelagic sedimentation bottom currents on terrace, gently inclined section upper slope Gondwana shaped by water‐mass interface. Contourite mainly controlled oxic clear‐water (documented moderately completely bioturbated limestones hydrogenetic ferromanganese nodules, low organic‐carbon contents), at times also an anoxic water mass (featured organic‐rich coquinas absent sparse bioturbation predominantly syngenetic framboidal pyrites). Biostratigraphic data overall architecture display palaeoceanographic hydrodynamic associated shifting inner terrace characterized alongslope channel small mounded drift its downslope margin. Energetic furthermore caused abraded surfaces, i.e. plain areas non‐deposition localized erosion, sandy condensation layers. microfacies reflects repeated alternation between suspension deposition, winnowing fines, bedload traction, dynamic bypassing reworking, together concomitant seafloor cementation. Coquinas planktonic nektonic organisms identified integral parts sequences showing inverse normal grading. Hiatal lag concentrations intraclasts, nodules conodonts often drape hardgrounds erosional surfaces midpoint these frequently incomplete sequences. This Devonian case provides opportunity investigate spatial temporal variability bed‐scale regard drift‐scale architecture. In addition, high‐resolution record starting point for unravelling pattern oceanic circulation greenhouse world.

Language: Английский

---

Spatio-temporal distribution of global stromatolites through geological time identified by a large language model approach

Frontiers in Earth Science, Journal Year: 2025, Volume and Issue: 13

Published: March 31, 2025

Introduction A substantial amount of data embedded within diverse literature makes it time-consuming to manually extract and compile extensive datasets. The use large language models has become essential for the efficient extraction analysis big data. This study utilizes ChatGPT-4 reconstruct a global database stromatolites, spanning from Precambrian present, enhance our understanding their spatial temporal dynamics throughout geological time. Methods process involved several steps: First, PDF documents containing stromatolite were gathered converted into text format. Second, was employed on occurrences, including locations, ages, strata, facies types each sentence in documents. Third, duplicates removed, organized three categories: 3,248 unique location-age pairs, 2,723 strata-age 1,723 strata-age-facies type combinations. Additionally, 2,565 paleogeographical locations stromatolite-bearing rocks reconstructed using modern latitude longitude coordinates corresponding Phanerozoic ages. Results newly obtained dataset reveals that occurrences peaked during Proterozoic, declined Early Phanerozoic, exhibited fluctuations Phanerozoic. Seven hotspots identified: United States, Australia, India, Canada, China, England, Russia. From Cambrian Jurassic, stromatolites predominantly distributed low middle latitudes, shifting higher latitudes Cretaceous Quaternary. proportion inland aquatic relative marine varied, ranging 10% 30% Mesoarchean Middle Mesoproterozoic, decreasing less than Late Mesoproterozoic Paleozoic, increasing 10%–30% Devonian remaining high (39%–53%) Discussion findings highlight variability shedding light evolution these microbial structures over distribution patterns suggest significant shifts environmental conditions provide valuable insights ecological dynamics. organize body demonstrates potential advancing research paleobiology geology.

Language: Английский

---

Devonian Conodonts and Ostracods in the Harlik Arc, SW CAOB: Implications for Chronostratigraphy, Paleoecology and Tectono‐Paleogeography

Geological Journal, Journal Year: 2025, Volume and Issue: unknown

Published: April 14, 2025

ABSTRACT Conodonts and ostracods in the orogenic belt can provide valuable insights into timing effects of tectonic events. In this study, four species conodonts 24 are reported for first time Hongliugou Kalamaili Formations Harlik arc, southwestern Central Asian Orogenic Belt (SW CAOB). Among them, conodont Caudicriodus woschmidti is significant element lowermost Devonian zone, indicating that upper part Formation dates to earliest (Lochkovian) age. The ostracod assemblages identified characterised by dominance Palaeocopid Metacopina elements, respectively, suggesting a change environment from inner‐shelf hemipelagic outer‐shelf. This transgression associated with regional extension during Early Devonian, likely subjected retreating subduction Paleo‐Asian Ocean. Furthermore, paleobiogeographic analysis arc shows prominent correlation eastern North America southern Europe. suggests was probably located mid‐latitude region northern hemisphere, adjacent northeastern Laurentia‐Siberia continent, Middle Devonian.

Language: Английский

---

Devonian geoheritage of Siberia: A case of the northwestern Kemerovo region of Russia

Heliyon, Journal Year: 2023, Volume and Issue: 9(2), P. e13288 - e13288

Published: Jan. 31, 2023

Southern Siberia demonstrates significant richness of the geological environment, but its uniqueness remains known poorly. Four geosites represent sections Givetian–Famennian (Middle–Late Devonian) deposits formed in tectonically active zone where small terranes accreted with Siberian continent. There, carbonate deposition tropical conditions prevailed and rich ecosystems evolved. Three are dominated by unique palaeogeographical features (notable palaeobiogeographical changes, facies catastrophic outflow from palaeolake, Frasnian/Famennian mass extinction, palaeoreefs), one geosite is stratigraphical feature (regionally representative section boundary). Additionally, all localities Devonian marine invertebrates, them also a topographical expression palaeoreef. The semi-quantitative assessment these implies that can be ranked nationally three others regionally. All well accessible important for international research. It proposed to use new geopark development would facilitate geotourism growth study area and, thus, provide socio-economic benefits region.

Language: Английский

---

Temporal dynamics of Devonian reef communities: Insights into natural phase shifts and long-term resilience in the face of environmental variability

Palaeogeography Palaeoclimatology Palaeoecology, Journal Year: 2024, Volume and Issue: 648, P. 112264 - 112264

Published: May 15, 2024

Language: Английский

---