88 research outputs found
Upper Cretaceous paleosols of the Bain-Dzak section, southern Mongolia
© 2016, Pleiades Publishing, Ltd.Three paleosol profiles (FPS-profiles) are described from the Djadokhta Formation (Upper Cretaceous, Campanian), outcropping in the Bain-Dzak section (southern Gobi aimag, Mongolia). The new data allow the climate at the time of the formation of the Late Cretaceous FPS-profiles to be interpreted as semiarid with seasonal precipitation. The isolated fossil roots of higher plants preserved in situ in the FPS-1 profile of the Bain-Dzak section are described as a new species, Radicites gobiensis Naugolnykh, sp. nov
A new genus of male cones of voltzialean affinity, Uralostrobus voltzioides nov. gen., nov. sp., from the Lower Permian of the Urals (Russia)
© 2014 Elsevier Masson SAS. A new genus and species of male cones of coniferophyte from the Lower Permian (Artinskian and Kungurian) deposits of the Urals, Russia is described: Uralostrobus voltzioides Naugolnykh nov. gen., nov. sp. The cone shows characters typical of some representatives of conifers belonging to the order Voltziales: more or less isometrical bracts of rhombic shape, prolonged sporangia with attenuate apices, and bisaccate pollen of Illinites-type. General information on the associated female seed scales and vegetative leafy shoots is given as well
Fossil flora and stratigraphy of the Terrigenous Kungurian beds (Lower Permian) of the basin of the Barda River (Urals, Perm krai)
© 2014, Pleiades Publishing, Ltd. The stratigraphy and nomenclature of the most important sections of the Kungurian Stage composed of arenaceous-argillaceous deposits in the basin of the Barda River (Perm krai, Middle Urals) are characterized using paleobotanical and palynological data. A new genus Astrogaussia Naugolnykh, gen. nov. is established for female reproductive organs of the gymnosperm order Vojnovskyales from the Carboniferous and Permian deposits of Angaraland and the Subangaran ecotonic belt, represented by headlike aggregations of sterile scales and seed stalks, with attached orthotropic seeds with a well-developed integumental wing. New combinations are proposed: Astrogaussia imbricata (Naugolnykh) Naugolnykh, comb. nov. (type species of the genus Astrogaussia), A. cristata (Neuburg) Naugolnykh, comb. nov., and A. relaxata (Radczenko) Naugolnykh, comb. nov
Fossil flora from the Kazanian (Middle Permian) Iva-Gora locality, Soyana River, Arkhangelsk Region, Russia
© 2015, Pleiades Publishing, Ltd. A floral assemblage from the Iva-Gora locality (middle reaches of the Soyana River, Arkhangelsk Region) is described. The flora includes lycopsids, sphenophytes, ferns, peltasperms (order Peltaspermales, families Peltaspermaceae and Angaropeltaceae), conifers, and vojnovskians (order Vojnovskyales). A new genus of isolated seeds, Megasylvella gen. nov., is established. Praephylladoderma sojanaeana (Zalessky, 1937) Naugolnykh, comb. nov., emend. nov. is newly combined. The new species Megasylvella ivagorica Naugolnykh, sp. nov. and Radicites trimorphus Naugolnykh, sp. nov. are described
Permocallipteris, a new genus from the Permian of Angaraland
This paper deals with Permian peltasperm foliages attributed to a new genus Permocallipteris Naug., gen. nov., which is characteristic of Angaraland paleofloristic realm. The genus is proposed for two- or three-pinnate fronds with entire-margined last order segments (pinnules), normally with obtuse round to slightly acute apex, wide base, well-developed midvein and pinnately disposed lateral (secondary) veins. The fronds always possess clear additional (intercalated) pinnules attached directly to the frond rachis. The intercalated pinnules can be identical to common pinnules or be slightly modified and form wings on the frond rachis. The epidermal-cuticular structure of Permocallipteris fronds is characterized. The leaves are amphystomatic, the lower (adaxial) leaf cuticle is thinner and has numerous papillae. Stomata are monocyclic to incompletely dicyclic, with thick cutinization of the subsidiary cells
A new matoniaceous fern from the Upper Triassic of the Caspian Depression in the context of florogenetic processes of transition from the Paleozoic to Mesozoic
© 2015, Pleiades Publishing, Ltd. A new matoniaceous fern species of the genus Phlebopteris Brongniart from the Upper Triassic of the Caspian Depression (Zhylyoiskii District, Atyrau Region, Kazakhstan) is described. It is represented by both sterile and fertile leaves preserved in situ, including the structure of sporangia and spores. The main trends in the evolution of ferns at transition from the Paleozoic to Mesozoic are discussed
A new find of the fossil Cyclosorus from the Eocene of South China and its paleoclimatic implication
© 2015, The Botanical Society of Japan and Springer Japan. The thelypteroid ferns are widely distributed across tropical regions around the world, but information about their fossil representatives is scarce. A new species, Cyclosorus scutum Naugolnykh, Wang, Han et Jin was discovered from the Eocene Changchang Formation of Hainan Island, South China, and is described on the basis of sterile and fertile leaves, sori, sporangia and spores preserved in situ. Discovery of this new species clearly shows that climatic conditions of that time in this area were humid, i.e. warm and wet
New Kinds of Acoustic Solitons
We find that the modified sine-Gordon equation belonging to the class of the
soliton equations describes the propagation of extremely short transverse
acoustic pulses through the low-temperature crystal containing paramagnetic
impurities with effective spin S=1/2 in the Voigt geometry case. The features
of nonlinear dynamics of strain field and effective spins, which correspond to
the different kinds of acoustic solitons, are studied.Comment: 9 pages, 1 figur
Radiation Properties of Synthesized under Different Conditions Hydroxyapatite
The aim of the study is investigating of the formation mechanisms of radiation paramagnetic defects in synthesized carbonized hydroxyapatite. The response to ionizing radiation exposure was studied by the electron paramagnetic resonance method.Исследование частично поддерживалось госзаданием «Спин» Г.р. № 122021000036-3
Upper Cretaceous paleosols of the Bain-Dzak section, southern Mongolia
© 2016, Pleiades Publishing, Ltd.Three paleosol profiles (FPS-profiles) are described from the Djadokhta Formation (Upper Cretaceous, Campanian), outcropping in the Bain-Dzak section (southern Gobi aimag, Mongolia). The new data allow the climate at the time of the formation of the Late Cretaceous FPS-profiles to be interpreted as semiarid with seasonal precipitation. The isolated fossil roots of higher plants preserved in situ in the FPS-1 profile of the Bain-Dzak section are described as a new species, Radicites gobiensis Naugolnykh, sp. nov
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