998 resultados para Homogeneous zones


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Introduction. Russia’s annexation of the Crimea and subsequent meddling in Ukraine does not constitute a game-changer. It is just a reminder that at least since the war with Georgia in 2008 Russia has been and still is playing the same game: a “game of zones”, aimed at (re)establishing an exclusive sphere of influence. Many of us Europeans had forgotten that, or had pushed it to the back of our minds, preferring to believe that we were not engaged in a zero-sum game in our eastern neighbourhood. While we were dealing with Ukraine, we tended also to forget the crises still going on in our southern neighbourhood, in Libya, Mali, Syria and now Iraq. Spilling over from Syria, extremist militias may establish their own “zone” in the Middle East, which would de-stabilize the entire region. In order to prevent that game-changer from materializing, another game-changer may be necessary: a rapprochement with Iran. Europe must assume responsibility for security in its entire neighbourhood, both east and south. The challenge is great – but so are Europe’s means.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Analogue model experiments using both brittle and viscous materials were performed to investigate the development and interaction of strike-slip faults in zones of distributed shear deformation. At low strain, bulk dextral shear deformation of an initial rectangular model is dominantly accommodated by left-stepping, en echelon strike-slip faults (Riedel shears, R) that form in response to the regional (bulk) stress field. Push-up zones form in the area of interaction between adjacent left-stepping Riedel shears. In cross sections, faults bounding push-up zones have an arcuate shape or merge at depth. Adjacent left-stepping R shears merge by sideways propagation or link by short synthetic shears that strike subparallel to the bulk shear direction. Coalescence of en echelon R shears results in major, through-going faults zones (master faults). Several parallel master faults develop due to the distributed nature of deformation. Spacing between master faults is related to the thickness of the brittle layers overlying the basal viscous layer. Master faults control to a large extent the subsequent fault pattern. With increasing strain, relatively short antithetic and synthetic faults develop mostly between old, but still active master faults. The orientation and evolution of the new faults indicate local modifications of the stress field. In experiments lacking lateral borders, closely spaced parallel antithetic faults (cross faults) define blocks that undergo clockwise rotation about a vertical axis with continuing deformation. Fault development and fault interaction at different stages of shear strain in our models show similarities with natural examples that have undergone distributed shear.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The spatial data set delineates areas with similar environmental properties regarding soil, terrain morphology, climate and affiliation to the same administrative unit (NUTS3 or comparable units in size) at a minimum pixel size of 1km2. The scope of developing this data set is to provide a link between spatial environmental information (e.g. soil properties) and statistical data (e.g. crop distribution) available at administrative level. Impact assessment of agricultural management on emissions of pollutants or radiative active gases, or analysis regarding the influence of agricultural management on the supply of ecosystem services, require the proper spatial coincidence of the driving factors. The HSU data set provides e.g. the link between the agro-economic model CAPRI and biophysical assessment of environmental impacts (updating previously spatial units, Leip et al. 2008), for the analysis of policy scenarios. Recently, a statistical model to disaggregate crop information available from regional statistics to the HSU has been developed (Lamboni et al. 2016). The HSU data set consists of the spatial layers provided in vector and raster format as well as attribute tables with information on the properties of the HSU. All input data for the delineation the HSU is publicly available. For some parameters the attribute tables provide the link between the HSU data set and e.g. the soil map(s) rather than the data itself. The HSU data set is closely linked the USCIE data set.