English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/209065
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL | DATACITE
Exportar a otros formatos:


Glendonite occurrences in the Tremadocian of Baltica: first Early Palaeozoic evidence of massive ikaite precipitation at temperate latitudes

AuthorsÁlvaro, J.J.; Popov, L.E; Holmer, L.E.; Bauert, H.; Ghobadi Pour, M.; Dronov, A.V.; Lehnert, O.; Hints, O.; Männik, P.; Zhang, Z.; Zhang, Z.
Issue Date2019
PublisherSpringer Nature
CitationScientific Reports 9 (2019)
AbstractThe Tremadocian (Early Ordovician) is currently considered a time span of greenhouse conditions with tropical water surface temperature estimates, interpolated from oxygen isotopes, approaching 40 °C. In the mid-latitude Baltoscandian Basin, conodonts displaying low δ O values, which suggest high temperatures (>40 °C) in the water column, are in contrast with the discovery of contemporaneous glendonite clusters, a pseudomorph of ikaite (CaCO ·6H O) traditionally considered as indicator of near-freezing bottom-water conditions. The massive precipitation of this temperature sensitive mineral is associated with transgressive conditions and high organic productivity. As a result, the lower Tremadocian sediments of Baltoscandia apparently contain both “greenhouse” pelagic signals and near-freezing substrate indicators. This paradox points to other primary controlling mechanisms for ikaite precipitation in kerogenous substrates, such as carbonate alkalinity, pH and Mg/Ca ratios, as recently constrained by laboratory experiments. Preservation of “hot” conodonts embedded in kerogenous shales rich in δ O-depleted glendonites suggests both the onset of sharp thermal stratification patterns in a semi-closed basin and the assumed influence of isotopically depleted freshwater yielded by fluvial systems.
Publisher version (URL)http://dx.doi.org/10.1038/s41598-019-43707-4
Identifiersdoi: 10.1038/s41598-019-43707-4
issn: 2045-2322
Appears in Collections:(IGEO) Artículos
Files in This Item:
File Description SizeFormat 
Glendonite occurrences.pdf3,73 MBUnknownView/Open
Show full item record
Review this work

Related articles:

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.