Changes in foraminiferal assemblages and environmental conditions during the T-OAE (Early Jurassic) in the northern Lusitanian Basin, Portugal

Reolid, Matías; Duarte, Luís V.; Rita, Patrícia

doi:10.1016/j.palaeo.2019.01.022

Cited by 33 publications

(23 citation statements)

References 83 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The dominance of shallow infauna and the record of potential deep infauna such as Eoguttulina (MG-J3) and Lenticulina (MG-K) indicate good tiering as well as unrestricted trophic resources and oxygen availability. The same good tiering for foraminiferal assemblages is reported for the top of the Pliensbachian in the Lusitanian Basin (Rita et al, 2016;Reolid et al, 2019a), the Basque-Cantabrian Basin (Herrero, 1998), Cardigan Bay Basin (Reolid et al, 2019b), Atlasic Basin (Reolid et al, 2012b(Reolid et al, , 2013, and Umbria-Marche Basin (Bartolini et al, 1992), among others. The ostracods in the upper part of the Pliensbachian are also diverse in the Cueva del Agua section, and the record of bioclasts of other benthic organisms -echinoid, ophiuroid, and holothurian plates -confirms the favourable conditions at the seafloor.…”

Section: Prebiotic Crisissupporting

confidence: 69%

“…A similar distribution of facies is described for the northern Lusitanian Basin in the Coimbra-Rabaçal region (e.g. Duarte and Soares, 1993;Duarte, 1998;Reolid et al, 2019a). The lower Toarcian in this region corresponds to the Sao Gião Formation.…”

Section: Interpretation Of Facies and Microfaciessupporting

confidence: 69%

“…The lower interval is constituted by marly limestones with the Leptaena member followed by thinbedded limestones with the Hildaites member having parallel lamination and cross-lamination. Watkinson (1989) and Duarte (1997) interpreted the thin-bedded limestones as tempestitic-turbiditic deposits, also related to tectonic reactivation (Duarte and Soares, 1993;Duarte, 1997) and enhanced storm activity (Reolid et al, 2019a). This interpretation resembles that of the Cueva del Agua section.…”

Section: Interpretation Of Facies and Microfaciesmentioning

confidence: 93%

“…Hesselbo et al, 2007;Ruebsam et al, 2020a). This global change led to a biotic crisis constituting a secondorder mass extinction for benthic organisms (Little and Benton, 1995;Aberhan and Fürsich, 2000;Cecca and Macchioni, 2004;Wignall et al, 2005;Gomez and Goy, 2011;Danise et al, 2013Danise et al, , 2019Caruthers et al, 2014;Rita et al, 2016), M. Reolid: Microfossil assemblages and geochemistry for interpreting the Jenkyns Event probably driven by oxygen depletion affecting many platforms and deep oceanic environments (Röhl et al, 2001;Bucefalo Palliani et al, 2002;Wignall et al, 2005;Hermoso et al, 2009;Caruthers et al, 2014;Them et al, 2018;Reolid et al, 2012aReolid et al, , 2019a. Oxygen-depleted conditions in marine ecosystems in some areas reached generalized anoxia and euxinia (e.g.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Microfossil assemblages and geochemistry for interpreting the incidence of the Jenkyns Event (early Toarcian) in the south-eastern Iberian Palaeomargin (External Subbetic, SE Spain)

Reolid¹

2020

J. Micropalaeontol.

View full text Add to dashboard Cite

Abstract. By studying the facies, geochemistry, and microfossil assemblages of the uppermost Pliensbachian and lower Toarcian of the Cueva del Agua section, I was able to appraise the impact of the Jenkyns Event in the eastern part of the South Iberian Palaeomargin (Western Tethys). Depleted oxygen conditions are envisaged for the Polymorphum–Serpentinum Zone boundary (lower Toarcian), represented by dark marls, precisely in a laminated interval. The decrease in the α diversity of foraminifera and ostracods, along with greater proportions of opportunists such as Lenticulina, Eoguttulina, and Cytherella just before the negative carbon isotopic excursion (CIE), would indicate a disturbance of the environmental conditions during the initial phase of the biotic crisis. The peak of the biotic crisis is characterized by an absence of trace fossils, increased organic matter content, an increased Mo∕Al ratio, and negative CIE and δ18O, as well as fewer specialist forms and more opportunists. This biotic crisis peak is related to oxygen-depleted conditions in the bottom waters and in the sediment pore water, while warming negatively affected microfauna – to the point of leaving a barren benthic horizon in the record. Recovery is evidenced by the occurrence of carbonate layers with hummocky cross-stratification and a decrease in organic matter content, the Mo∕Al ratio, and the trace fossil record. In terms of microfauna, the first phase of recovery shows highly abundant foraminifera, ostracods, and microgastropods, mainly opportunist forms. After the proliferation of opportunist forms, a second phase of recovery is marked by a progressive increase in α diversity.

show abstract

Section: Prebiotic Crisissupporting

confidence: 69%

Section: Interpretation Of Facies and Microfaciessupporting

confidence: 69%

Section: Interpretation Of Facies and Microfaciesmentioning

confidence: 93%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Microfossil assemblages and geochemistry for interpreting the incidence of the Jenkyns Event (early Toarcian) in the south-eastern Iberian Palaeomargin (External Subbetic, SE Spain)

Reolid¹

2020

J. Micropalaeontol.

View full text Add to dashboard Cite

show abstract

“…Moreover, seawater temperature is still higher than during the Late Pliensbachian [21]. The conditions are, however, not as severe as during the Pli–Toa boundary event, or during the onset of the T-OAE, which is also supported by the response of other groups of marine biota in the Peniche section [29,30,90–92].…”

Section: Discussionmentioning

confidence: 97%

Mechanisms and drivers of belemnite body-size dynamics across the Pliensbachian–Toarcian crisis

et al. 2019

View full text Add to dashboard Cite

Body-size reduction is considered an important response to current climate warming and has been observed during past biotic crises, including the Pliensbachian–Toarcian crisis, a second-order mass extinction. However, in fossil cephalopod studies, the mechanisms and their potential link with climate are rarely investigated and palaeobiological scales of organization are not usually differentiated. Here, we hypothesize that belemnites reduce their adult size across the Pliensbachian–Toarcian boundary warming event. Belemnite body-size dynamics across the Pliensbachian–Toarcian boundary in the Peniche section (Lusitanian Basin, Portugal) were analysed based on the newly collected field data. We disentangle the mechanisms and the environmental drivers of the size fluctuations observed from the individual to the assemblage scale. Despite the lack of a major taxonomic turnover, a 40% decrease in rostrum volume is observed across the Pliensbachian–Toarcian boundary, before the Toarcian Oceanic Anoxic Event where belemnites go locally extinct. The pattern is mainly driven by a reduction in adult size of the two dominant species, Pseudohastites longiformis and Passaloteuthis bisulcata. Belemnite-size distribution is best correlated with fluctuations in a palaeotemperature proxy (stable oxygen isotopes); however, potential indirect effects of volcanism and carbon cycle perturbations may also play a role. This highlights the complex interplay between environmental stressors (warming, deoxygenation, nutrient input) and biotic variables (productivity, competition, migration) associated with these hyperthermal events in driving belemnite body-size.

show abstract

Paleoenvironmental reconstruction of the Middle Jurassic rocks in western India using benthic foraminifera

Jain¹,

Alhussein²,

Ahmed³

et al. 2023

Facies

View full text Add to dashboard Cite

Changes in foraminiferal assemblages and environmental conditions during the T-OAE (Early Jurassic) in the northern Lusitanian Basin, Portugal

Cited by 33 publications

References 83 publications

Microfossil assemblages and geochemistry for interpreting the incidence of the Jenkyns Event (early Toarcian) in the south-eastern Iberian Palaeomargin (External Subbetic, SE Spain)

Microfossil assemblages and geochemistry for interpreting the incidence of the Jenkyns Event (early Toarcian) in the south-eastern Iberian Palaeomargin (External Subbetic, SE Spain)

Mechanisms and drivers of belemnite body-size dynamics across the Pliensbachian–Toarcian crisis

Paleoenvironmental reconstruction of the Middle Jurassic rocks in western India using benthic foraminifera

Contact Info

Product

Resources

About