“…These ␦ 13 C excursions are fairly well constrained by means of biostratigraphy and have been formally named, usually from sections in North America (Bergström et al, 2009). In comparison, very few studies have been undertaken in the Lower and Middle Ordovician strata (Buggisch et al, 2003;Ainsaar et al, 2007Ainsaar et al, , 2010Munnecke et al, 2011;Edwards and Saltzman, 2014). The result is that this part of the Ordovician history is far less understood in terms of carbon isotope chemostratigraphy.…”