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Brian R Bell - One of the best experts on this subject based on the ideXlab platform.
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s tephenson d l oughlin s c m illward d w aters c n w illiamson i t 2002 carboniferous and Permian igneous rocks of great britain north of the variscan front geological conservation review series volume 27 xviii 374 pp peterborough joint nature conse
Geological Magazine, 2004Co-Authors: Brian R BellAbstract:This beautifully produced hard-back volume provides a detailed account of the myriad of igneous rocks related to back-arc extension during the Carboniferous Period, followed by the intracontinental rifting events of the Permian Period, north of the Variscan Front within Great Britain. These volcanic and intrusive rocks crop out over a large area, from the Orkney Islands in the north, to Derbyshire in the south, although it is within the Midland Valley of Scotland that they are most abundant. Site-selection criteria are presented, comprising the factors international importance, presence of exceptional features, and representativeness. All aspects of these rocks are dealt with, including introductory sections on history of research, tectonic setting, magma …
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S TEPHENSON , D., L OUGHLIN , S. C., M ILLWARD , D., W ATERS , C. N. & W ILLIAMSON , I. T. 2002. Carboniferous and Permian Igneous Rocks of Great Britain North of the Variscan Front . Geological Conservation Review Series Volume 27. xviii + 374 pp. P
Geological Magazine, 2004Co-Authors: Brian R BellAbstract:This beautifully produced hard-back volume provides a detailed account of the myriad of igneous rocks related to back-arc extension during the Carboniferous Period, followed by the intracontinental rifting events of the Permian Period, north of the Variscan Front within Great Britain. These volcanic and intrusive rocks crop out over a large area, from the Orkney Islands in the north, to Derbyshire in the south, although it is within the Midland Valley of Scotland that they are most abundant. Site-selection criteria are presented, comprising the factors international importance, presence of exceptional features, and representativeness. All aspects of these rocks are dealt with, including introductory sections on history of research, tectonic setting, magma …
Henk Visscher - One of the best experts on this subject based on the ideXlab platform.
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fungal virulence at the time of the end Permian biosphere crisis
Geology, 2011Co-Authors: Henk Visscher, Mark A Sephton, Cindy V LooyAbstract:Throughout the world, latest Permian records of organic-walled microfossils are characterized by the common presence of remains of filamentous organisms, usually referred to the palynomorph genus Reduviasporonites . Although generally regarded as indicators of global ecological crisis, fundamental controversy still exists over the biological and ecological identity of the remains. Both fungal and algal affinities have been proposed. We seek to resolve this enigma by demonstrating close morphological similarity of the microfossils to resting structures (monilioid hyphae, sclerotia) of Rhizoctonia , a modern complex of soil-borne filamentous fungi that includes ubiquitous plant pathogens. By analogy with present-day forest decline, these findings suggest that fungal virulence may have been a significant contributing factor to widespread devastation of arboreal vegetation at the close of the Permian Period.
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fungal event and palynological record of ecological crisis and recovery across the Permian triassic boundary
Geology, 1995Co-Authors: Yoram Eshet, Michael R. Rampino, Henk VisscherAbstract:The end of the Permian Period was marked by the most severe mass extinction in the geologic record. Detailed quantitative study of pollen and spores from shallow-marine deposits spanning the Permian-Triassic (P-Tr) boundary in Israel reveals a sequence of palynological-ecological stages reflecting a major crisis among land plants. The disappearance of the gymnosperm-dominated palynoflora of the Late Permian Lueckisporites virkkiae Zone is recorded at a claystone horizon containing almost exclusively abundant fungal remains and carbonized terrestrial plant debris. This ‘‘fungal spike’’ is followed by a zone dominated by marine acritarchs and a succession showing ecological recovery with abundantlycopodsporesandeventualreappearanceofbisaccategymnospermpolleninthe EarlyTriassic.ThelatestPermianproliferationoffungiisrecognizableworldwideandcan be correlated with other paleontological and geochemical markers of a global ecological disaster.
Torsten Wappler - One of the best experts on this subject based on the ideXlab platform.
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New fossil insects from the Anisian (Lower to Middle Muschelkalk) from the Central European Basin (Germany and The Netherlands)
PalZ, 2017Co-Authors: Timo Van Eldijk, Gerard Goris, Adam Haarhuis, Jos Lankamp, Herman Winkelhorst, J.w.f. Reumer, André Nel, Torsten WapplerAbstract:The Palaeozoic–Mesozoic transition is characterized not only by the most massive Phanerozoic mass extinction at the end of the Permian Period, but also its extensive aftermath and a prolonged Period of major biotal recovery during the succeeding Middle to Late Triassic. Particularly, Anisian insect species from units of the Lower to Middle Muschelkalk from the Central European Basin are rare. The specimens described here originated from the Anisian Wellenkalk facies (Lower Muschelkalk), Vossenveld Formation of the Winterswijk quarry, The Netherlands, and from the orbicularis Member (lowermost Middle Muschelkalk, Anisian) of Esperstedt near Querfurt (Saxony-Anhalt). Thus, the described insect remains from Winterwijk and Esperstedt expand our knowledge about Middle Triassic terrestrial arthropod communities and their palaeodiversity. A new species of Chauliodites (C. esperstedti sp. nov) is introduced.
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The earliest known holometabolous insects
Nature, 2013Co-Authors: André Nel, Patrick Roques, Patricia Nel, Jakub Prokop, Alexander A. Prokin, Thierry Bourgoin, Jacek Szwedo, Dany Azar, Laure Desutter-grandcolas, Torsten WapplerAbstract:The Eumetabola (Endopterygota (also known as Holometabola) plus Paraneoptera) have the highest number of species of any clade, and greatly contribute to animal species biodiversity. The palaeoecological circumstances that favoured their emergence and success remain an intriguing question. Recent molecular phylogenetic analyses have suggested a wide range of dates for the initial appearance of the Holometabola, from the Middle Devonian epoch (391 million years (Myr) ago) to the Late Pennsylvanian epoch (311 Myr ago), and Hemiptera (310 Myr ago). Palaeoenvironments greatly changed over these Periods, with global cooling and increasing complexity of green forests. The Pennsylvanian-Period crown-eumetabolan fossil record remains notably incomplete, particularly as several fossils have been erroneously considered to be stem Holometabola (Supplementary Information); the earliest definitive beetles are from the start of the Permian Period. The emergence of the hymenopterids, sister group to other Holometabola, is dated between 350 and 309 Myr ago, incongruent with their current earliest record (Middle Triassic epoch). Here we describe five fossils--a Gzhelian-age stem coleopterid, a holometabolous larva of uncertain ordinal affinity, a stem hymenopterid, and early Hemiptera and Psocodea, all from the Moscovian age--and reveal a notable penecontemporaneous breadth of early eumetabolan insects. These discoveries are more congruent with current hypotheses of clade divergence. Eumetabola experienced episodes of diversification during the Bashkirian-Moscovian and the Kasimovian-Gzhelian ages. This cladogenetic activity is perhaps related to notable episodes of drying resulting from glaciations, leading to the eventual demise in Euramerica of coal-swamp ecosystems, evidenced by floral turnover during this interval. These ancient species were of very small size, living in the shadow of Palaeozoic-era 'giant' insects. Although these discoveries reveal unexpected Pennsylvanian eumetabolan diversity, the lineage radiated more successfully only after the mass extinctions at the end of the Permian Period, giving rise to the familiar crown groups of their respective clades.
Tian Qiu - One of the best experts on this subject based on the ideXlab platform.
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a new geological map of the western junggar north xinjiang nw china implications for paleoenvironmental reconstruction
Episodes, 2013Co-Authors: Yongfeng Zhu, Bo Chen, Tian QiuAbstract:Recently, new geochronological data and geological observations including the discovery of garnet amphibolite, Ordovician micro-fossils, unconformable contact between the ophiolitic melange related flysch and the Devonian to Early Carboniferous terrestrial volcano-sedimentary strata provide critical evidences for Paleo-environmental reconstruction in the western Junggar (Xinjiang, China). Two different geological layers could be clearly identified: the Early Paleozoic metamorphic terrane mainly consists of ophiolitic melange and flysch, and the Late Paleozoic volcano-sedimentary units lying on the ophiolitic melange and flysch. Both of these layers were intruded by granitic to dioritic magma during the Late Carboniferous to Early Permian Period. Based on these data, a new geological map for the western Junggar has been compiled, which is essential not only for better understanding of the geological evolution but also for exploration of mineral resources.
Ross Damiani - One of the best experts on this subject based on the ideXlab platform.
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A new Triassic procolophonoid reptile and its implications for procolophonoid survivorship during the Permo-Triassic extinction event.
Proceedings of The Royal Society B: Biological Sciences, 2001Co-Authors: Sean P. Modesto, Hans-dieter Sues, Ross DamianiAbstract:A reptile specimen from the Lystrosaurus Assemblage Zone of the Beaufort Group, lowermost Triassic of South Africa, represents a new procolophonoid parareptile. Sauropareion anoplus gen. et sp. nov. is identified as the sister taxon of Procolophonidae in a phylogenetic analysis of procolophonoids. Stratigraphic calibration of the most parsimonious tree reveals that four of the six procolophonoid lineages originating in the Permian Period extended into the succeeding Triassic Period. This relatively high taxic survivorship (67%) across the Permo–Triassic boundary strongly suggests that procolophonoids were little if at all affected by the mass extinction event that punctuated the end of the Palaeozoic Era ( ca. 251 million years ago).