Upper Ordovician carbon isotope records in the Siljan district, Sweden
2009 (English)In: Absolutely final meeting of IGCP 503: Ordovician palaeogeography and palaeoclimate - Copenhagen 2009 - August 31 – September 4, Copenhagen: Geological Museum, Natural History Museums , 2009, 23-24 p.Conference paper (Other academic)
The Upper Ordovician Boda Limestone and the unconformably overlying Glisstjärn Formation in the Siljan district, Sweden, were sampled for carbon isotope analysis. The aim is to combine chemo- andAbsolutely final meeting of IGCP 503: Ordovician palaeogeography and palaeoclimate - Copenhagen 2009 - August 31 – September 424biostratigraphy for detailed regional correlation. This may help further studies of the time interval spanning the two-phased end Ordovician extinction. Expanding upon the study by Schmitz & Bergström (2007), five quarries, eight sections (669 samples) were studied; two sections each in Kallholn, Osmundsberget, and Solberga, and one section each in Östbjörka and Jutjärn. The Glisstjärn Formation is exposed only in one section at Kallholn, both sections at Osmundsberget, and possibly at one section in Solberga. A cephalopod event bed is recognized in one section in Kallholn and the two sections in Osmundsberget. Additionally, a thick coquina consisting of the brachiopod Hindella is found in all quarries except Solberga. The Hirnantian Isotope Carbon Excursion (HICE) was positively identified in seven of the eight sections. The peak occurs at the Hindella bed in all sections. The beginning of the excursion in Osmundsberget is placed slightly higher than in the previous study, at about 14 m from the top of the Boda Limestone, which means it is above the level with the brachiopod Holorhynchus (identified both in Osmundsberget and Solberga). In Osmundsberget, Östbjörka and Jutjärn, sampling of the deeper parts of the Boda Limestone yielded δ13C values between + 1 and + 3 ‰, with two or three peaks higher than + 3 ‰, that may be correlated between the sections
Place, publisher, year, edition, pages
Copenhagen: Geological Museum, Natural History Museums , 2009. 23-24 p.
IdentifiersURN: urn:nbn:se:uu:diva-111356OAI: oai:DiVA.org:uu-111356DiVA: diva2:280781
IGCP 503: Ordovician palaeogeography and palaeoclimate - Copenhagen 2009 - August 31 – September 4