PALAEOXYLOTOMICAL STUDIES in the CENOZOIC PETRIFIED FORESTS of GREECE. PART TWO – CONIFERS

This paper reports the palaeoxylotomical study of petrified conifer remains from Velitzelos collection, originating from some fossiliferous sites of Greece, especially from the Aegean area (Evros, Limnos, Lesbos), aged of late Oligocene to early Miocene. Ten species were identified: Cupressinoxylon akdikii, Juniperoxylon acarcae, Tetraclinoxylon velitzelosii, Taxodioxylon gypsaceum, Taxodioxylon taxodii, Glyptostroboxylon rudolphii, Glyptostroboxylon tenerum, Pinuxylon pineoides, Pinuxylon halepensoides and Pinuxylon sp. aff. Pinus canariensis. These new identifications add new elements to the forest assemblages of the Oligocene - Miocene Greek flora, useful for understanding the evolution of the Cenozoic palaeovegetation and palaeoclimate in the Aegean area. © 2021 The authors. All right reserved

Palaeoxylotomical studies in the Cenozoic petrified forests of Greece. Part one-palms

The paper reports a palaeoxylotomical study of petrified palm remains (stem, root, rachis) collected from some fossil sites of Greece (Evros, Lemnos, Lesbos and Kastoria) aged to the late Oligocene to early Miocene. Five species of Palmoxylon were identified: P. daemonoropsoides (Unger) Kirchheimer, corr., P. chamaeropsoides Iamandei et Iamandei, sp. nov., P. coryphoides Ambwani et Mehrotra, P. sabaloides Greguss, P. trachycarpoides Iamandei et Iamandei, sp. nov. and P. phoenicoides Hofmann. Also found were two species of Rhizopalmoxylon (R. daemonoropsoides Iamandei et Iamandei, sp. nov., R. phoenicoides Iamandei et Iamandei, sp. nov.) and Palmocaulon sp. aff. Phoenix L. These new identifications add new elements to the forest assemblages of the Oligocene-Miocene Greek flora, useful for understanding the evolution of the Cenozoic palaeoclimate in the Aegean area. © 2019 Dimitrios Velitzelos et al., published by Sciendo

Fossil wood and Mid-Eastern Europe terrestrial palaeobiogeography during the Jurassic–Early Cretaceous interval

Palaeobiogeography plays an important role in the evolution of continental plants. This has been demonstrated mainly for modern biota and for past biota on a very large scale only. During the Jurassic–Early CretaceousMid-Eastern Europe was an archipelago, thus a particularly suitable area for a more detailed study. We investigated the area's plant palaeobiogeography, using fossil wood, with information from both a literature survey and investigation of new samples. There is a clear north–south differentiation of wood floras. The northern part of the archipelago, which was connected by a shallow sea, has a homogenous flora. A small terrane in the south, separated by true oceanic crust, seems to have had a peculiar flora, lacking widely distributed elements but displaying an endemic taxon with Gondwanan affinities. Compared toWestern Europe,Mid-Eastern Europe has a Jurassic–Early Cretaceous wood flora with similar diversity, except for the Late Jurassic, when it was limited to a single taxon, the widespread Agathoxylon Hartig. The wood flora of northern Gondwana is less diverse across the time interval under consideration, except for the Late Jurassic again. Taphonomic bias cannot be ruled out, but this low diversity during the Late Jurassic suggests stressful climatic conditions for Mid-Eastern Europe

Numerical analysis of the stresses appeared around some lifting ears from a cylinder used in the petrochemical industry

Abstract In the petrochemical industry there are many devices with cylindrical shapes such as: columns and horizontal or vertical vessels. All these devices, during the fitting or transporting processes must be raised using some special ears. Using the same methodology with those presented in [1,2,4,5], the paper presents the stresses that appear around some raising ears (made from curved beams) welded on the cylindrical shell. The connection between the ears and cylinder are analysed in two cases: when the ear is welded directly on the cylinder and when the ear is welded on a reinforcement pad welded on the cylinder. Maximum stresses obtained in certain elements of the cylinder (for different thicknesses of the shell) are compared with the allowable limits of the materials.</jats:p

Experimental results regarding the strains and stresses appeared around some lifting ears from a cylinder used in the petrochemical industry

Abstract During transporting or raising processes any equipment used in petrochemical industry needs some special ears to be easy and safety manipulated. In the paper are presented some experimental results measured around some lifting ears welded on a cylinder. A special experimental device has been manufactured to complete the experiments. The acquisition data have been registered with a modern Quantum system equipped with a Catman Easy software.</jats:p

Soil fauna: key to soil organic matter dynamics and modelling. Handbook of methods.

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<em>Ecpagloxylon mathiesenii</em> gen. nov. et sp. nov., a Jurassic wood from Greenland with several primitive angiosperm features

International audienceFossil wood specimens from the late Early-early Middle Jurassic of Jameson Land, Eastern Greenland, have several unexpected features: tracheids of irregular size and shape, thinly pitted ray cell walls, heterogeneous rays, partially scalariform radial pitting, both areolate and simple pits, and pitted elements associated with rays. These characters diverge markedly from those typical of Jurassic wood, which usually conform to those of modern conifers. Although this combination of features is not encountered in any extant angiosperm, each has been documented in one or several extant homoxylous angiosperms, particularly Amborella, Trochodendron, and Tetracentron. As these wood specimens are not found in connection with any reproductive part, it is impossible to confidently assign them to the angiosperms. If a Jurassic angiosperm did exist, however, it might well have had a similar wood. This material is an early bench-mark in the evolution that led from homoxylous conifer-like wood to that of the angiosperms. Its particular biogeography (Arctic) could renew the discussion about the area of origin of the angiosperm