microgastropod fauna from the upper devonian cephalopod bed and overlying lower tournaisian strata of the original reference section of the shishtu formation have been examined. twenty genera and one unknown genus have been identified. the original aragonite shells have been replaced either by pyrite or fluorapatite

The early Tournaisian (Carboniferous) stage represents a key episode in the evolution of vertebrates. It follows end-Devonian Hangenberg extinction event, which led to major perturbation both terrestrial and aquatic vertebrate ecosystems, resulted significant restructuring assemblages. However, few faunal associations this age have been described, our understanding turnover across Devonian-Carb...

Elgaecrinus uralicus gen. et sp. nov. (Crotalocrinitidae, Crinoidea, Echinodermata), a reef-dwelling crinoid, is described from the Lochkovian (Lower Devonian) of the western slope of the Middle Urals. The arms of the new species are laterally fused in each radius and represent, as in the similar genus Crotalocrinites, uniform semi-mobile plates surrounding the central cavity above the oral sur...

Abstract The timing of assembly and tectonic origins terranes in the northern Cordillera Alaska, British Columbia, Pacific Northwest are debated. Stikinia, a long‐lived arc terrane, has an enigmatic regional Mesozoic accretionary history its remain unconstrained. Zircon U‐Pb geochronology Lu‐Hf isotopic data on Triassic–Jurassic sedimentary igneous rocks from central Stikinia shed light terrane...