title: Glendonites track methane seepage in Mesozoic polar seas
metadata.name: dc.contributor.author
metadata.value: Ершова, Виктория Бэртовна
metadata.lang: -
metadata.name: dc.date.accessioned
metadata.value: 2020-09-08T16:53:59Z
metadata.lang: -
metadata.name: dc.date.available
metadata.value: 2020-09-08T16:53:59Z
metadata.lang: -
metadata.name: dc.date.issued
metadata.value: 2017
metadata.lang: -
metadata.name: dc.identifier.uri
metadata.value: http://hdl.handle.net/11701/19298
metadata.lang: -
metadata.name: dc.description.abstract
metadata.value: During the Phanerozoic, Earth has experienced a number of transient
  global warming events associated with major carbon cycle perturbations.
  Paradoxically, many of these extreme greenhouse episodes
  are preceded or followed by cold climate, perhaps even glacial conditions,
  as inferred from the occurrence of glendonites in high latitudes.
  Glendonites are pseudomorphs of ikaite (CaCO3·6H2O), a hydrated
  carbonate mineral increasingly stable at low temperatures. Here,
  we show that methane seepage and oxidation provide an overriding
  control on Mesozoic glendonite formation (i.e., ikaite fossilization).
  Geochemical and petrological analyses of 33 Early Jurassic to Early
  Cretaceous glendonites from five sections in Siberia (Russia) reveal
  that most of their infilling carbonate phases are reminiscent of methane-
  derived authigenic carbonates. Bulk glendonites and surrounding
  sediments exhibit exceptionally high and low carbon isotope values
  (+20‰ to −45‰ VPDB [Vienna Peedee belemnite]), typical for carbon
  sources linked to methane generation and oxidation. Gas inclusion
  data confirm the presence of methane and longer-chain hydrocarbon
  gases, suggesting a thermogenic source for the methane. Glendonitebearing
  layers can be traced for hundreds of kilometers, suggesting
  widespread trapping of methane in the sub-seafloor during the Jurassic.
  As such, glendonites constitute an unexplored archive for detecting
  past episodes of methane release and oxidation in polar settings.
metadata.lang: en_GB
metadata.name: dc.publisher
metadata.value: Geological Society of America
metadata.lang: en_GB
metadata.name: dc.title
metadata.value: Glendonites track methane seepage in Mesozoic polar seas
metadata.lang: en_GB
metadata.name: dc.type
metadata.value: Article
metadata.lang: en_GB
resources.filename: Morales-et-al-2017-Geology.pdf
resources.url: https://dspace.spbu.ru/bitstream/11701/19298/1/Morales-et-al-2017-Geology.pdf
resources.format: Adobe PDF
resources.size: 1,14 MB