Matches in SemOpenAlex for { <https://semopenalex.org/work/W2111607661> ?p ?o ?g. }
- W2111607661 endingPage "212" @default.
- W2111607661 startingPage "200" @default.
- W2111607661 abstract "The present contribution focusses on ecostratigraphic fluctuations of foraminiferal assemblages occurring during the benthic biotic crisis corresponding to the Early Toarcian anoxic event. We aim at understanding the response of benthic biota to the environmental changes that occurred during the crisis in a high latitude setting and compare with previous data from total organic carbon (TOC) and δ13C from previous works. The Kelimyar River section exposes a Lower Jurassic marine succession made up of siltstones, sandy siltstones (uppermost Pliensbachian) and black shales (Lower Toarcian) deposited close to the Early Jurassic North Pole in a relatively deep continental shelf. The Pliensbachian sediments are represented by a foraminiferal assemblage dominated by epifauna, mainly Trochammina, but showing a progressive diminution in diversity. This suggests an unfavourable microhabitat for infaunal forms, probably involving salinity fluctuations. Although the opportunist Trochammina tolerated salinity fluctuations, the decreasing proportions of aragonitic and calcitic hyaline foraminifera indicate the progressive deterioration of the benthic environment. A context of relative sea-level fall in the Arctic palaeobasin during the margaritatus Zone and the beginning of the viligaensis ammonite Zone related to an abrupt climatic cooling would explain these environmental changes (including salinity fluctuations) that lead to decreased diversity and even the disappearance of calcitic and aragonitic forms. The debut of the falciferum Zone (Lower Toarcian) is characterised by laminated black shales, high total organic carbon, a negative carbon isotopic excursion, and an abrupt decrease in the foraminiferal abundance and diversity. These features indicate oxygen-restricted conditions in the sea-bottom. Only opportunist Trochammina shows a rapid increase in abundance after the debut of the black shales, congruent with the relation of this genus with high TOC and a poorly oxygenated sediment water interface. Trochammina was able to colonise the sea-bottom after the development of hypoxic conditions in the Kelimyar River section. These adverse conditions occurred just after the negative carbon isotopic excursion and maximum values of TOC and correlate with the climatic warming that occurred in the Arctic palaeobasins referred to by previous authors. Detailed analysis of the sea-bottom recolonisation points to a foraminiferal replacement in which distinct foraminiferal morphogroups reach their optimum values. Finally, despite certain differences, the benthic foraminiferal assemblages from Kelimyar River section are comparable with those from the North African palaeomargin in the Ratnek El Kahla section (Algeria), thus illustrating an equivalent response of benthic foraminiferal assemblages to the Early Toarcian biotic crisis. In both cases the composition of assemblages, diversity and abundance of foraminifera were sensitive to restricted oxygen conditions, and opportunist species did colonize the sea bottom after this biotic crisis." @default.
- W2111607661 created "2016-06-24" @default.
- W2111607661 creator A5005197053 @default.
- W2111607661 creator A5021196149 @default.
- W2111607661 creator A5043860913 @default.
- W2111607661 date "2013-04-01" @default.
- W2111607661 modified "2023-09-28" @default.
- W2111607661 title "Ecostratigraphy of benthic foraminifera for interpreting Arctic record of Early Toarcian biotic crisis (Northern Siberia, Russia)" @default.
- W2111607661 cites W1581942403 @default.
- W2111607661 cites W1963495482 @default.
- W2111607661 cites W1966261917 @default.
- W2111607661 cites W1967570668 @default.
- W2111607661 cites W1978761019 @default.
- W2111607661 cites W1979337539 @default.
- W2111607661 cites W1984441670 @default.
- W2111607661 cites W1989552422 @default.
- W2111607661 cites W1990868760 @default.
- W2111607661 cites W1991980404 @default.
- W2111607661 cites W1997252211 @default.
- W2111607661 cites W2008268722 @default.
- W2111607661 cites W2011272671 @default.
- W2111607661 cites W2016225258 @default.
- W2111607661 cites W2016261456 @default.
- W2111607661 cites W2016613637 @default.
- W2111607661 cites W2017185961 @default.
- W2111607661 cites W2017306011 @default.
- W2111607661 cites W2018732069 @default.
- W2111607661 cites W2028191042 @default.
- W2111607661 cites W2030448143 @default.
- W2111607661 cites W2034149620 @default.
- W2111607661 cites W2034233781 @default.
- W2111607661 cites W2044408877 @default.
- W2111607661 cites W2049104028 @default.
- W2111607661 cites W2052713532 @default.
- W2111607661 cites W2054879664 @default.
- W2111607661 cites W2059106731 @default.
- W2111607661 cites W2059505522 @default.
- W2111607661 cites W2059534529 @default.
- W2111607661 cites W2059758277 @default.
- W2111607661 cites W2060155491 @default.
- W2111607661 cites W2063621731 @default.
- W2111607661 cites W2068638898 @default.
- W2111607661 cites W2070661327 @default.
- W2111607661 cites W2071050112 @default.
- W2111607661 cites W2074629798 @default.
- W2111607661 cites W2075532353 @default.
- W2111607661 cites W2075850102 @default.
- W2111607661 cites W2077671227 @default.
- W2111607661 cites W2081732342 @default.
- W2111607661 cites W2084201797 @default.
- W2111607661 cites W2084527013 @default.
- W2111607661 cites W2085086651 @default.
- W2111607661 cites W2093290405 @default.
- W2111607661 cites W2095960552 @default.
- W2111607661 cites W2104754992 @default.
- W2111607661 cites W2111598480 @default.
- W2111607661 cites W2123643957 @default.
- W2111607661 cites W2125385806 @default.
- W2111607661 cites W2125549160 @default.
- W2111607661 cites W2128428640 @default.
- W2111607661 cites W2134419042 @default.
- W2111607661 cites W2146368895 @default.
- W2111607661 cites W2149733981 @default.
- W2111607661 cites W2152510189 @default.
- W2111607661 cites W2163293439 @default.
- W2111607661 cites W2317966087 @default.
- W2111607661 cites W2318996289 @default.
- W2111607661 doi "https://doi.org/10.1016/j.palaeo.2013.03.003" @default.
- W2111607661 hasPublicationYear "2013" @default.
- W2111607661 type Work @default.
- W2111607661 sameAs 2111607661 @default.
- W2111607661 citedByCount "31" @default.
- W2111607661 countsByYear W21116076612013 @default.
- W2111607661 countsByYear W21116076612014 @default.
- W2111607661 countsByYear W21116076612015 @default.
- W2111607661 countsByYear W21116076612016 @default.
- W2111607661 countsByYear W21116076612017 @default.
- W2111607661 countsByYear W21116076612018 @default.
- W2111607661 countsByYear W21116076612019 @default.
- W2111607661 countsByYear W21116076612020 @default.
- W2111607661 countsByYear W21116076612021 @default.
- W2111607661 countsByYear W21116076612022 @default.
- W2111607661 countsByYear W21116076612023 @default.
- W2111607661 crossrefType "journal-article" @default.
- W2111607661 hasAuthorship W2111607661A5005197053 @default.
- W2111607661 hasAuthorship W2111607661A5021196149 @default.
- W2111607661 hasAuthorship W2111607661A5043860913 @default.
- W2111607661 hasConcept C108970007 @default.
- W2111607661 hasConcept C111368507 @default.
- W2111607661 hasConcept C127313418 @default.
- W2111607661 hasConcept C129513315 @default.
- W2111607661 hasConcept C151730666 @default.
- W2111607661 hasConcept C158787203 @default.
- W2111607661 hasConcept C18903297 @default.
- W2111607661 hasConcept C2777598122 @default.
- W2111607661 hasConcept C2779343474 @default.
- W2111607661 hasConcept C2780368712 @default.
- W2111607661 hasConcept C518008717 @default.