The δ13C chemostratigraphy of the Upper Ordovician Mjosa Formation at Furuberget near Hamar, southeastern Norway: Baltic, Trans-Atlantic, and Chinese relations

Whereas no studies have previously been carried out on the delta C-13 chemostratigraphy of the Sandbian-Katian (Upper Ordovician) succession anywhere in Norway, such investigations in Sweden and the East Baltic region have made the delta C-13 chemostratigraphy of that interval well known. 1 an attempt to document for the first time the presence of the globally distributed and stratigraphically important Guttenberg Carbon Isotope Excursion (GICE), 45 samples were collected at 2 m intervals through the Furnesfjorden and Galas members of the Mjosa Formation from two sections at Furuberget in the Nes-Hamar District 70 km north of the City of Oslo. Relatively high delta C-13 values, which are interpreted to represent the GICE, were obtained throughout the Galls Member. The presence of this delta C-13 excursion in the middle part of the Mjosa Formation, combined with biostratigraphic and other evidence, are used for detailed correlations of the Mjosa Formation with other successions in Baltoscandia, North America, and on the Yangtze Platform in southern China.