The distribution and dispersal histories of Eurypterida are examined in a phylogenetic and palaeogeographic context. It is suggested that all the eurypterid clades originated and had most of their evolutionary history on the palaeocontinents of Laurentia, Baltica, Avalonia, the Rheno–Hercynian Terrane and some presence in Siberia. The Siluro–Devonian Stylonurina and the eurypterine superfamilie...

Conodonts representing 38 species of 26 genera have been identified in samples from Upper Ordovician rocks at three central Nevada localities. Ranges of these species and associated graptolites are used graphically to determine correlation of the strata considered with an evolving composite standard that includes information from Ordovician strata at more than 100 localities in North America. R...

The Silurian–Devonian plant radiation was an event triggered by the progressive colonization of subaerial habitats. Nevertheless, it is still unclear whether this globally uniform or alternative diversification scenarios emerged depending on geographical context. Here, we report early land diversity patterns across different previously defined palaeogeographical units (i.e., Laurussia, Siberia,...

Intensive sampling of uppermost Silurian to lowermost Devonian levels the marine sequence Roberts Mountains Formation exposed in Birch Creek II section, Nevada has yielded assemblages vertebrate microremains dominated by acanthodian scales. Taxonomic assessment vertebrates represented shows a suite and succession taxa most similar those recorded from contemporary circum-Arctic assemblages, with...

A number of Paleo-Indian artifacts found in Western Wisconsin lithic assemblages were observed to be made of an unidentified olive green colored chert. A macroscopic examination of these artifacts, and comparison with known possible sources suggested that the material might be Silurian Chert Type II from the Door Pennisula in eastern Wisconsin. Attributed analysis and comparison with lithic deb...

Green Lakes State Park, located -15 km east of Syracuse, New York near the village of Fayetteville, is a stunning geologic and limnologic wonderland (Fig. 1). Located along the axis of a narrow glacial meltwater channel, the Park consists of two small, moderately deep (maximum water depth of -53 m) lake basins (Green Lake and Round Lake), protected along their flanks by steep walls of Silurian ...

In this study, the methane adsorption capacity of kerogen isolated from Cambrian, Silurian, and Permian shales impact soluble organic matter (SOM) on these were investigated. The results reveal that 1) varies in a broad range, 14.48 to 23.22 cm 3 /g for Cambrian kerogens, 15.50 36.06 Silurian 10.71 11.15 kerogens; 2) accounts 33.67–70.23% total Palaeozoic extracted shales, demonstrating is prim...

Coral reefs form the most diverse of all marine ecosystems on the Earth. Corals are among their main components and owe their bioconstructing abilities to a symbiosis with algae (Symbiodinium). The coral-algae symbiosis had been traced back to the Triassic (ca 240 Ma). Modern reef-building corals (Scleractinia) appeared after the Permian-Triassic crisis; in the Palaeozoic, some of the main reef...