Diplocraterion Parallelum Research Articles

Trace fossils from the Silurian Chaleurs Group of southeastern Gaspé Peninsula, Québec

A suite of previously undescribed trace fossils from the three main sections of the Silurian (Chaleurs Group) of the southeastern Gaspé Peninsula are examined in detail. The ichnofauna includes a diverse assemblage of forms produced essentially by vermiform and other problematica (Chondrites,Cosmorhaphe; Diplocraterion parallelum Torell, Gyrophyllites, Monocraterion, Planolites annularius Walcott, Planolites cf. beverleyensis (Billings), Rhizocorallium cf. irregulare (Mayer), Scalarituba missouriensis Weller, Skolithos, Zoophycos, pholadid-like bur-rows and grazing trails). The trace fossils occur in four distinctive and recurring associations. Three of these associations, the Scalarituba – Cosmorhaphe, Chondrites, and Diplocraterion associations are useful paleobathymetric and paleoenvironmental indicators, as they all occur in lagoonal, intertidal, or shallow subtidal regimes. The Scalarituba – Cosmorhaphe and Chondrites associations are characterized by shallow burrows and developed in moderately low energy conditions. The monospecific Diplocraterion association developed on an unstable substrate subject to higher rates of sedimentation. The fourth, Zoophycos association, is found in rocks deposited in variable water depths and is a much less useful paleobathymetric and paleoen-vironmental indicator so that conclusions regarding its distribution must be made with extreme caution.