نتایج جستجو برای: devonian

تعداد نتایج: 2127  

Journal: :American Journal of Science 1882

Journal: :The Journal of Geology 1900

Journal: :journal of sciences islamic republic of iran 0

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

Journal: :Annals of the Missouri Botanical Garden 1974

Journal: :The Open Geology Journal 2014

Journal: :Geologica Carpathica 2010

Journal: :Palaeogeography, Palaeoclimatology, Palaeoecology 2022

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...

2017
Sergey V. Rozhnov

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...

Journal: :Tectonics 2021

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...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید