نتایج جستجو برای: permian

تعداد نتایج: 3143  

2005
G. J. RETALLACK A. H. JAHREN N. D. SHELDON R. CHAKRABARTI C. A. METZGER R. M. H. SMITH

The Permian ended with the largest of known mass extinctions in the history of life. This signal event has been difficult to recognize in Antarctic non-marine rocks, because the boundary with the Triassic is defined by marine fossils at a stratotype section in China. Late Permian leaves (Glossopteris) and roots Vertebraria), and Early Triassic leaves (Dicroidium) and vertebrates (Lystrosaurus) ...

Journal: :Proceedings. Biological sciences 2007
Peter D Roopnarine Kenneth D Angielczyk Steve C Wang Rachel Hertog

Studies of the end-Permian mass extinction have emphasized potential abiotic causes and their direct biotic effects. Less attention has been devoted to secondary extinctions resulting from ecological crises and the effect of community structure on such extinctions. Here we use a trophic network model that combines topological and dynamic approaches to simulate disruptions of primary productivit...

A. Ernst H. Yarahmadzahi M.N. Gorgij

The Fistulipora microparallela (Yang and Lu, 1962) species is described for the first time from the Sakmarian deposits of the Sarab section in Lut Block, Central Iran. This species has been reported only from the Permian (Cisuralian-Guadalupian) of the Qilianshan and Kankerin formations, and the Baliqliq Group (Upper Carboniferous to Lower Permian) of Western Xinjiang, China.

2011
Alexei S. Bashkuev

The family Mesopanorpodidae is revised. Most taxa referred to this family are not related to the type genus Mesopanorpodes Tillyard, 1918. The type species of the latter, Mesopanorpodes wianamattensis,is closely related to Mesopsyche Tillyard, 1917. Therefore Mesopanorpodes is transferred to Mesopsychidae Tillyard, 1917 (= Mesopanorpodidae Tillyard, 1918, syn. n.).The earliest Mesopsychidae are...

2011
Daniil S. Aristov Sergey Yu. Storozhenko

A new replacement name Permulidaenom. n. is proposed for the Permian family Aliculidae Storozhenko, 1997 (Insecta: Grylloblattida). A review of Permulidae is given. All genera and species are redescribed and illustrated. A key to genera of Permulidae is given. New taxa of Permulidae are described: Permula edemskiisp. n., Sojanopermula rasnitsynisp. n., Kazanalicula reductagen. et sp. n., Mezena...

Journal: :Science 2003
Asish R Basu Michail I Petaev Robert J Poreda Stein B Jacobsen Luann Becker

Multiple chondritic meteorite fragments have been found in two sedimentary rock samples from an end-Permian bed at Graphite Peak in Antarctica. The Ni/Fe, Co/Ni, and P/Fe ratios in metal grains; the Fe/Mg and Mn/Fe ratios in olivine and pyroxene; and the chemistry of Fe-, Ni-, P-, and S-bearing oxide in the meteorite fragments are typical of CM-type chondritic meteorites. In one sample, the met...

2018
Ray Kenny

The upper carbonate member of the Kaibab Formation in northern Arizona (USA) was subaerially exposed during the end Permian and contains fractured and zoned chert rubble lag deposits typical of karst topography. The karst chert rubble has secondary (authigenic) silica precipitates suitable for estimating continental weathering temperatures during the end Permian karst event. New oxygen and hydr...

Journal: :journal of sciences islamic republic of iran 0

a totall of 500 early permian samples from the chal-i-sheh formation in the zagros basin were examined palynollogically in order to determine the stratigraphical age of the formation and to assess the palaeogeopaphicd relatianships of this basin to the southern and northern hemispheres during the early permian. fifty-eight taxa were recorded including 46 pollen, 10 spore and 2 acritarch species...

2011
Jakub Prokop André Nel

Three new palaeopteran insects are described from the Middle Permian (Guadalupian) of Salagou Formation in the Lodève Basin (South of France), viz. the diaphanopterodean Alexrasnitsyniidaefam. n., based on Alexrasnitsynia permianagen. etsp. n., the ParelmoidaePermelmoa magnificagen. etsp. n., and Lodevohymen lapeyrieigen. etsp. n. (in Megasecoptera or Diaphanopterodea, family undetermined). In ...

2015
Ellen K. Schaal Matthew E. Clapham Brianna L. Rego Steve C. Wang Jonathan L. Payne

—The small size of Early Triassic marine organisms has important implications for the ecological and environmental pressures operating during and after the end-Permian mass extinction. However, this “Lilliput Effect” has only been documented quantitatively in a few invertebrate clades. Moreover, the discovery of Early Triassic gastropod specimens larger than any previously known has called the ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید