2.1 Geologic setting
Epeiric seaways were widespread throughout much of the Late Ordovician
as a result of elevated eustatic sea levels (Rasmussen et al., 2019).
Widespread carbonate deposition dominated these epeiric seaways with
carbonate successions found even in mid-latitude settings such as the
paleocontinent of Baltica (Fig. 1). Subsequently, nearly every marine
setting records a major decrease in sea level during the latest Katian
and Hirnantian marked by subaerially exposed carbonate platforms and
significantly reduced shallow-water marine habitats.