The Late Ordovician (~459–444 million years ago) was characterized by global cooling, glaciation and severe mass extinction. These events may have been driven increased delivery of the nutrient phosphorus (P) to ocean associated increases in marine productivity, but it is not clear why this occurred two pulses identified geological record. We link both cooling phases—and extinction—to volcanic ...

The Late Ordovician Mass Extinction wiped out 85% of animal species in two phases (LOME1 and LOME2). kill mechanisms for the extinction are debated, but deteriorating climate expansion marine anoxia appear to have been important factors. Nevertheless, spatial extent intensity its temporal relationship with extinctions not well understood. Here, we review existing global paleoredox proxy data ba...

. Early to middle Paleozoic arbonates ofeastern North America have been pervasively remagnetized. In order to determine the process of remagnetization, scanning and scanning transmission electron microscopy have been used to characterize magnetite in thin sections and in concentrated separates. Samples included Ordovician Knox carbonates from east Tennessee, Ordovician Trenton limestone and Dev...

New geochronological and geochemical data document a new widely distributed succession of igneous sedimentary rocks within the Sibumasu that extend from SW Yunnan through SE Asia as far Sumatra. Our revealed presence an Ordovician-Silurian (mainly ?490–430 Ma) zone. The early Paleozoic granites in zone display similar elemental Sr–Nd–Pb–Hf isotopic compositions. They were derived common mixed s...

This study compiles the U-Pb and 40Ar/39Ar geochronology of metasedimentary, migmatitic granitic rocks Sierra Albarrana Domain, based on data recently published by authors together with other bibliographic sources. Maximum depositional ages (MDA) magmatic metamorphic events are discussed. MDAs suggest that this domain was deposited during middle Cambrian (ca. 511) zoned zircon grains indicate m...

Ordovician and Silurian glacial erratics of the Laerheide area (Lower Saxony, north-western Germany) bear well-preserved graptolites. The faunas provide important information on the origin and transport direction of the sediments preserved in a kame, representing the Drenthe stadial of the Saalian glaciation. The faunas even include species not commonly encountered in the successions of mainlan...

Abstract Anticosti Island, eastern Canada, records an exceptionally thick and well-exposed Ordovician/Silurian boundary section that hosts a series of diverse marine invertebrate faunas across the Late Ordovician mass extinction. However, base terminal stage, Hirnantian, has been difficult to identify on due lack traditional Hirnantia fauna within Upper Ellis Bay Formation. Previously, eponymou...