Analyses of the stress field in southeastern France from earthquake focal mechanisms

Due to the apparent deformation field heterogeneity, the stress regimes around the Provence block, from the fronts of the Massif Central and Alpine range up to the Ligurian Sea, were not well defined. To improve the understanding of the SE France stress field, we determine new earthquake focal mechanisms and we compute the present-day stress states by inversion of the 89 available focal mechanisms around the Provence domain, including the 17 new ones calculated in the current study. This study provides evidence of 6 different deformation domains around the Provence block with different tectonic regimes. On a regional scale, we identify three zones characterised by significantly different stress regimes: a western one affected by an extensional stress (normal faulting) regime, a southeastern one characterised by a compressional stress (reverse to strike-slip faulting) regime with NNW- to WNW-trending σ1 and a northeastern one, i.e., the Digne nappe front, marked by an NE-trending compression. Note that the Digne nappe back domain is controlled by an extensional regime that is deforming the western alpine core. This extensional regime could be a response to buoyancy forces related to the Alpine high topography. The stress regimes in the southeast of the Argentera Massif and around the Durance fault are consistent with a coherent NNW-trending σ1 that implies a left-lateral component of the active reverse oblique-slip of the Moyenne Durance Fault. In the Rhone Valley, an E-trending extension characterises the tectonic regime that implies a normal component of the present-day Nîmes fault displacement. This study provides evidence for short-scale variation of the stress states that reflect abrupt change in the boundary force influences on upper crustal fragments (blocks). These spatial stress changes around the Provence block result from the coeval influence of forces applied at both its extremities, i.e., in the north-east, the Alpine front push and in the southeast, the northward African plate drift. Besides these boundary forces, the influence of the mantle plume under the Massif Central can be superimposed along the western block boundary

Corrigendum: Early Pennsylvanian Odonatoptera from the Xiaheyan locality (Ningxia, China): new material, taxa, and perspectives

No abstract is available for this article. doi:10.1002/mmng.201390000</a

Early Pennsylvanian Odonatoptera from the Xiaheyan locality (Ningxia, China): new material, taxa, and perspectives

Data on Odonatoptera species from the Xiaheyan locality (Ningxia, China; Early Pennsylvanian) described so far are complemented based on abundant new material. Several taxonomic and nomenclatural adjustments are proposed. The species Tupus readi Carpenter, 1933 is transferred to the genus Shenzhousia Zhang & Hong, 2006 in Zhang et al. (2006), and therefore should be referred to as Shenzhousia readi (Carpenter, 1933) n. comb. The monotypic genus Sinomeganeura Ren et al., 2008 is synonymized with Oligotypus Carpenter, 1931. As a consequence the type species of the former must be referred to as Oligotypus huangheensis (Ren et al., 2008) n. comb. The monotypic genus Paragilsonia Zhang, Hong & Su, 2012 in Su et al. (2012) is synonymized with Tupus Sellards, 1906. As a consequence the type-species of the former is to be referred to as Tupus orientalis (Zhang, Hong & Su, 2012 in Su et al. (2012)) n. comb. The monotypic genus Sinierasiptera Zhang, Hong & Su, 2012 in Su et al. (2012) is synonymized with Erasipterella Brauckmann, 1983. As a consequence the type-species of the former is to be referred to as Erasipterella jini (Zhang, Hong & Su, 2012 in Su et al. (2012)) n. comb. In addition Aseripterella sinensis n. gen. et sp. and Sylphalula laliquei n. gen. et sp. are described. The "strong oblique distal" cross-vein, located in the area between RA and RP is found to occur more extensively than previously expected. It is believed to be a structure distinct from the subnodal cross-vein, and therefore deserves to be referred to by a distinct name (viz. "postsubnodal cross-vein"). Odonatoptera from the Xiaheyan locality cover a broad range of sizes. Factors that could have promoted the evolution of large-sized Odonatoptera are briefly reviewed. The permissive conditions prevailing during the Pennsylvanian, and the existence of an elaborated food web, are emphasized as putative positive factors. The new taxonomic treatment suggests that genera documented in the Lower Permian, such as Shenzhousia and Oligotypus, stem from the early Pennsylvanian, and implies a high resilience of these taxa when facing the Pennsylvanian–Permian environmental perturbations. doi:10.1002/mmng.201300006</a

At last, a Pennsylvanian stem-stonefly (Plecoptera) discovered

<p>Abstract</p> <p>Background</p> <p>Stem-relatives of many winged insect orders have been identified among Pennsylvanian fossils (Carboniferous Period). Owing to their presumed 'basal' position in insect phylogeny, stoneflies were expected to occur at this period. However, no relative has ever been designated convincingly.</p> <p>Results</p> <p>In this paper, we report specimens belonging to a new fossil insect species collected from the Tupo Formation (Pennsylvanian; China). The wing venation of <it>Gulou carpenteri </it><b>gen. et sp. nov</b>. exhibits character states diagnostic of the order Plecoptera, but lack character states shared by unequivocal representatives of the order. Derived from this identification, the delimitation of the fossil species is ascertained based on comparison of several extant stonefly species. This comparative analysis allowed a trait present in <it>G. carpenteri </it><b>gen. et sp. nov</b>., but rarely occurring in extant species, to be documented and highlighted as atavistic. Affinities of taxa formerly proposed as putative stem-stoneflies are reconsidered in the light of the new discovery.</p> <p>Conclusions</p> <p><it>Gulou carpenteri </it><b>gen. et sp. nov</b>. is considered the only genuine Plecoptera reported from the Pennsylvanian. Continuing efforts on the systematics of Pennsylvanian winged insects indicate a fauna more diverse than previously appreciated. It suggests that insects already had a long, yet undocumented, history by this time.</p

A new, rare and small “lobeattid” species (Insecta: Archaeorthoptera) found at Xiaheyan (Pennsylvanian; Ningxia, China)

A new species of stem Orthoptera, namely Phtanomiamia gui gen. et sp. nov., is described from the Pennsylvanian Xiaheyan locality in China. Despite the intensive collecting efforts undertaken at this locality, a single forewing was recovered. It shares with the “lobeattid” Miamia spp. two peculiar traits, namely a broad ScP–R/RA area and a very early branching of CuA&thinsp;+&thinsp;CuPa. On the other hand, it displays a free portion of CuA (between its divergence from M&thinsp;+&thinsp;CuA and its fusion with CuPa), a trait allowing exclusion of the new species from Miamia, to which it is most likely very closely related.</p

Hydrogen Energy Storage: New Techno-Economic Emergence Solution Analysis

International audienceThe integration of various renewable energy sources as well as the liberalization of electricity markets are established facts in modern electrical power systems. The increased share of renewable sources within power systems intensifies the supply variability and intermittency. Therefore, energy storage is deemed as one of the solutions for stabilizing the supply of electricity to maintain generation-demand balance and to guarantee uninterrupted supply of energy to users. In the context of sustainable development and energy resources depletion, the question of the growth of renewable energy electricity production is highly linked to the ability to propose new and adapted energy storage solutions. The purpose of this multidisciplinary paper is to highlight the new hydrogen production and storage technology, its efficiency and the impact of the policy context on its development. A comprehensive techno/socio/economic study of long term hydrogen based storage systems in electrical networks is addressed. The European policy concerning the different energy storage systems and hydrogen production is explicitly discussed. The state of the art of the techno-economic features of the hydrogen production and storage is introduced. Using Matlab-Simulink for a power system of rated 70 kW generator, the excess produced hydrogen during high generation periods or low demand can be sold either directly to the grid owners or as filled hydrogen bottles. The affordable use of Hydrogen-based technologies for long term electricity storage is verified

An insect wing discovered in the Early Permian Taiyuan Formation (Shanxi Province, China)

The first discovery of an insect wing from the Taiyuan Formation, near Yangquan City, Shanxi Province, China, is described. The combination of its wing venation characters makes it difficult to assign it to any known major Paleozoic group. The comparison is made among the new material, stem-Orthoptera species, and “fossil Grylloblattodea”. Further investigation on fossil insects from this locality is needed.</p

Design of a high voltage input – output ratio dc-dc converter dedicated to small power fuel cell systems

International audienceConsuming chemical energy, fuel cells produce simultaneously heat, water and useful electrical power [J.M. Andújar, F. Segura, Renew. Sust. Energy Rev. , 2309 (2009)], [J. Larminie, A. Dicks, , 2nd edn. (John Wiley & Sons, 2003)]. As a matter of fact, the voltage generated by a fuel cell strongly depends on both the load power demand and the operating conditions. Besides, as a result of many design aspects, fuel cells are low voltage and high current electric generators. On the contrary, electric loads are commonly designed for small voltage swing and a high V/I ratio in order to minimize Joule losses. Therefore, electric loads supplied by fuel cells are typically fed by means of an intermediate power voltage regulator. The specifications of such a power converter are to be able to step up the input voltage with a high ratio (a ratio of 10 is a classic situation) and also to work with an excellent efficiency (in order to minimize its size, its weight and its losses) [A. Shahin, B. Huang, J.P. Martin, S. Pierfederici, B. Davat, Energy Conv. Manag. , 56 (2010)]. This paper deals with the design of this essential ancillary device. It intends to bring out the best structure for fulfilling this function. Several dc-dc converters with large voltage step-up ratios are introduced. A topology based on a coupled inductor or tapped inductor is closely studied. A detailed modelling is performed with the purpose of providing designing rules. This model is validated with both simulation and implementation. The experimental prototype is based on the following specifications: the fuel cell output voltage ranges from a 50 V open-voltage to a 25 V rated voltage while the load requires a constant 250 V voltage. The studied coupled inductor converter is compared with a classic boost converter commonly used in this voltage elevating application. Even though the voltage regulator faces severe FC specifications, the measured efficiency reaches 96% at the rated power whereas conventional boost efficiency barely achieves 91.5% in the same operating conditions

A new triadotypomorphan insect from the Anisian (Middle Triassic), Buntsandstein facies, Spain

The species rubra sp. nov., a new triadotypomorphan insect from the Iberian Ranges, is described on the basis of a newly discovered specimen, found in fine grained sandstones of alluvial origin, in the lowermost part of the Eslida Formation (Buntsandstein facies), in the central part of the Iberian Ranges. The occurrence of a triadotypomorphan suggests an Anisian age of the Eslida Formation. The species represents the oldest Mesozoic insect described from Spain, and provides interesting information to better appreciate the process of ecosystems recovery after the Permian-Triassic boundary crisis.La especie rubra sp. nov., un nuevo insecto triadotipomorfo de la Cordillera Ibérica, es descrito en este trabajo en base a un nuevo espécimen hallado en un nivel de areniscas de grano fino de origen aluvial en la parte más baja de la Formación Eslida (facies Buntsandstein), en la zona central de la Cordillera Ibérica. La aparición de este triadotipomorfo confirma la edad Ansíense (Triásico Medio) de la Formación Eslida. La especie encontrada representa el insecto más antiguo hallado en el Mesozoico de España y una interesante información para comprender mejor el proceso de recuperación de los ecosistemas tras la crisis del límite Pérmico-Triásico