Brachiopod macrofaunal distribution through the upper Volkhov – lower Kunda (Lower Ordovician) rocks, Lynna River, St. Petersburg region

Abstract

The ranges of 27 brachiopod species, through the upper Volkhov-lower Kunda interval of the Lynna River section, are presented on the basis of over 17,500 specimens. Three depth-related ecological associations are recognized within the succession of alternating limestones and marls forming part of an array of nearshore to mid-shelf communities in an intracratonic setting. Faunal diversity is relatively stable throughout the section with little evidence for abrupt local extinctions or originations. The dominant orthoid and clitambonitoid assemblages, however, form the basis of the distinctive Baltic brachiopod province developed during this time interval.