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31.
Wilfried Heller 《GeoJournal》1998,46(3):199-205
This study evaluates some aspects of the socio-economic transformation of rural Romania with reference to the views of representative
organisations (at national, regional and local levels) and other experts. Interviews conducted in ten communes of nine Romanian
counties (‘judete’) focus attention on the advantages and disadvantages of system change experienced since 1989; the most
important problems and constraints for future socio-economic change; and appropriate policies and perspectives for development
in the immediate future. Wherever appropriate the claims of interviewees are substantiated through reference to statistics,
drawn in many cases from Chambers of Commerce & Industry (CCI). Local level representatives presented much more negative views
on recent change than their national and regional level counterparts, but all agreed on the crucial problem of capital shortage.
Thus while specific programmes to assist rural areas are justified, they cannot fully succeed until the national economy is
able to grow more rapidly and attract greater foreign investment.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
32.
Wilfried Brutsaert 《Boundary-Layer Meteorology》1979,16(3):365-388
A differential equation is obtained to describe the concentration of passive admixtures (water vapor, sensible heat, pollutants, CO2, etc.) of turbulent flow inside a dense and uniform vegetational canopy. The profiles of eddy diffusivity, wind speed and shear stress are assumed to be exponential decay functions of depth below the top of the canopy. This equation is solved for the case of a vegetation with constant concentration of the admixture at the foliage surfaces. The solution is used to formulate bulk mass or heat transfer coefficients, which can be applied to practical problems involving surfaces covered with a vegetation or with similar porous or fibrous roughness elements. The results are shown to be consistent with experimental data presented by Chamberlain (1966), Garratt and Hicks (1973) and Garratt (1978). Calculations with the model illustrate that, as compared to its behavior over surfaces with bluff roughness elements, ln(z 0/ z oc ) (where z 0 is the momentum roughness and Z oc the scalar roughness) for permeable roughness elements is relatively insensitive to u * and practically independent of z 0. 相似文献
33.
The following reactions involving gedrite were experimentally investigated at 500, 1,000 and 2,000 bars H2O pressure:
- (1)Mg, Fe, Al-chlorite + quartz ? gedrite + cordierite + H2O and 相似文献
34.
Dr. K. -H. Nitsch Professor Dr. H. G. F. Winkler 《Contributions to Mineralogy and Petrology》1965,11(5):470-486
The equilibrium curves for the reactions:
- (a)4 orthozoisite + 1 quartz ? 5 anorthite + 1 grossularite + 2 H2O. 相似文献
35.
It is attempted to determineT, P values for the lowgrade metamorphic facies. From geologic-petrographic observations and from experiments mineralreactions are outlined which characterize the zeolitic-, the glaucophane- and the greenschistfacies, respectively. Only such reactions are considered which are univariant if Pf=Ps; thus aP-T grid can be arrived at. Experimental data on the equilibria of the relevant reactions is taken from the literature and from own experiments. Experimental results are always checked against known field-observations. Contrary to current opinium, we arrive at rather higher temperatures for the beginning of the lowgrade metamorphic facies: Diagenesis. From sedimentation up to slightly below 300° C. Zeolitic facies. From slightly below 300° C up to about 400° C. Greenschistfacies. From about 400° C up to about 550° C. Glaucophaneschistfacies. Under pressures of at least 6–7 kb this facies begins somewhat above 300° C, probably at about 330° C, grading into high-pressure greenschistfacies. 相似文献
36.
37.
38.
Jürgen M. Reitner Wilfried Gruber Alexander Römer Rainer Morawetz 《Swiss Journal of Geoscience》2010,103(3):385-405
We present a study of the inneralpine basin of Hopfgarten focused on the analysis of basin fill in order to reveal its formation
in relation to paleo-ice flow and tectonics. The study is based on geological mapping as well as seismic (reflection and refraction)
and geoelectrical surveys. The oldest sequence in the basin, identified by seismic stratigraphy at 400 m below surface, consists
of coarse grained sediments of supposedly Oligocene to Miocene age, which subsided along faults linked to the Inn fault. Three
superimposed sequences, each displaying baselaps in contact with a subglacially formed unconformity and sigmoid foresets,
show pleniglacial conditions followed by a glaciolacustrine environment. The uppermost of these three sequences lies on top
of last glacial maximum till (LGM; Würmian Pleniglacial; MIS 2) and represents Termination I. The middle sequence is classified
as Termination II following the Rissian Pleniglacial (MIS 6). The oldest glacial sequence cannot be constrained chronostratigraphically
but might correlate with Termination V following the major glaciation of MIS 12. Limited glacial erosion during the LGM occurred
only during the ice build-up phase. Further overdeepening was impeded due to topographic barrier and mutual blockades of glaciers
within this highly dissected landscape. The occurrence and relative timing of the impediment was controlled by the onset of
transfluences and thus by the altitude of coles. The higher amount of overdeepening during older glacial periods is explained
by longer phases of free ice advance in the ice build up phase due to higher transfluences routes at that time. Thus, the
preservation of older Pleistocene sequences within the basin may be the result of the lowering of watersheds from one glaciation
to the next. Our model of an inverse relationship between glacial shaping of the surface and the subsurface may apply to similar
Alpine landscapes as well. 相似文献
39.
Errol Wiles Andrew Green Mike Watkeys Wilfried Jokat Ralf Krocker 《Geo-Marine Letters》2014,34(6):525-540
Although global thermohaline circulation pathways are fairly well known, the same cannot be said for local circulation pathways. Within the southwest Indian Ocean specifically there is little consensus regarding the finer point of thermohaline circulation. We present recently collected multibeam bathymetry and PARASOUND data from the northern Natal Valley and Mozambique Ridge, southwest Indian Ocean. These data show the Ariel Graben, a prominent feature in this region, creates a deep saddle across the Mozambique Ridge at ca. 28°S connecting the northern Natal Valley with the Mozambique Basin. Results show a west to east change in bathymetric and echo character across the northern flank of the Ariel Graben. Whereby eroded plastered sediment drifts in the west give way to aggrading plastered sediment drift in the midgraben, terminating in a field of seafloor undulations in the east. In contrast, the southern flank of the Ariel Graben exhibits an overall rugged character with sediments ponding in bathymetric depressions in between rugged sub/outcrop. It is postulated that this change in sea-floor character is the manifestation of deep water flow through the Ariel Graben. Current flow stripping, due to increased curvature of the graben axis, results in preferential deposition of suspended load in an area of limited accommodation space consequently developing an over-steepened plastered drift. These deposited sediments overcome the necessary shear stresses, resulting in soft sediment deformation in the form of down-slope growth faulting (creep) and generation of undulating sea-floor morphology. Contrary to previous views, our works suggests that water flows from west to east across the Mozambique Ridge via the Ariel Graben. 相似文献
40.
The African Easterly Jet South (AEJ-S) is an important feature of the central African mid tropospheric circulation and has been identified as a key contributor to convection over the region. This study uses 21-year (1983–2003) Reanalysis data sets of ERA-Interim, NCEP2 and MERRA2 to establish mechanisms related to AEJ-S dynamics. Results demonstrate that AEJ-S is dominated by rotational circulation and is maintained by a mid-level high that forms over the Kalahari region during September to November. Because of the role played by this high pressure system in the AEJ-S dynamics, an effort is made to understand how this anticyclone develops. We show that this mid-tropospheric high over the Kalahari region is established in response to lower tropospheric dry convection over the region from September to November. At the core of this high, anticyclonic circulation is induced and maintains AEJ-S located at the northern flank of the high. A link between AEJ-S dynamics and southern subtropical westerly waves is also revealed. It is shown that, when waves amplify over the southern subtropics, they modify lower tropospheric heating. Depending on the phase of the wave, this modifies the cross latitude temperature gradient throughout equatorial regions, therefore modulating the intensity of the jet. By clarifying the mechanisms that govern the AEJ-S, this research work contributes to insight into central Africa climate mechanisms and also suggests a link between central Africa and Southern Africa climate systems. This research work also improves the foundation of new mechanisms that help to identify suitable metrics for the evaluation of Global models over the Central Africa region. 相似文献