Fig. 4 in Ordovician polychaeturid polychaetes: Taxonomy, distribution and palaeoecology

Fig. 4. Sketch map showing selected occurrences of four species of polychaeturid polychaete genus Pteropelta in the Baltic Region. Note that the localities may expose strata of different stratigraphical intervals. The boundary between shallow and deeper shelf facies is tentative; it has shifted in time due to basin infilling and sea level changes. Thus, for instance, the occurrence of P. gladiata in the Ruhnu and Valga drill cores does not infer its relation to deeper shelf settings. All localities are boreholes, unless stated otherwise. For more information about the localities see the on−line catalogue at http://sarv.gi.ee.