Comparison of blocking versus non-blocking using the local energetics of kinetic energy divided in vertical mean and sheared flows
The AA. compared the composite fields of typical cases for blocking and non-blocking, which where selected using objective thresholds. The results of this study demonstrate the obvious difference in mechanical energy flux between the blocking
and the non-blocking about 1.5 days after the onset time. It is suggested that the convergence of mechanical energy flux around the eastern flank of the ridge is the necessary condition for the blocking formation. In addition, there is a significant
convergence of mechanical energy flux around the upstream jet at 4 days before the onset. This may be the precursor signal of the formation of blocking.
Ploughing blocks on the hillslopes are active under the present climatic conditions. A study on seven blocks during 1978-1980 showed that their annual movements ranging from 0.1 to 0.8 mm, are controlled largely by the combined effect of altitude
Properties of talus slopes composed of flat blocks
In this paper the AA. draw attention to a rarer kind of talus slopes, the ones mostly formed by flat stones as building blocks. One case study in Norway is examined as an example typifying the properties of flat-blocks taluses. From comparisons
of the geometrical characteristics and grain size distribution with taluses of the same rock type formed by regular blocks, remarkable differences are found, especially concerning the slope angle and the size distribution of blocks as a function of the distance from
the headwall. To understand the formation dynamics of flat-block taluses, the AA. also carried out some simple experiments with flat blocks falling onto an experimental board.
Transport and dispersal of organic debris (peat blocks) in upland fluvial systems
This paper assesses the mechanisms and pathways by which peat blocks are eroded and transported in upland fluvial systems. Observations and experiments from the north Pennines (UK) have been carried out on 2 contrasting river systems. Mapping
of peat block distributions and appraisal of reach-based sediment budgets clearly demonstrates that macro-size peat is an important stream load component. Results of peat block tracing using painted blocks indicate that once submerged, blocks of all sizes
are easily transported and blocks break down rapidly by abrasion. Vegetation and bars play an important role in trapping mobile peat.
Az Eszaki-kozéphegység vizfoldtani tombszelvénye Hydrogeological block diagram of the North-Hungarian Mountains
Compiled after the hydrogeological block diagram drawn in 1971 and from new borehole data. This block diagram covers almost all the major mountains or mountains sections with the neighbouring basins. It gives information for the evaluation
Ice-rich, redeposited diamicton blocks and associated structures in Quaternary outwash sediments of the Inn Valley near Innsbruck, Austria
This paper is an attempt to describe the composition, textures and structures of these redeposited glacial debris blocks (diamicton blocks) and the surrounding sediments, and to discuss their origin and climatic significance.
Liesegang blocks from sandstone beds of the Hojedk Formation, Kerman, Iran
In this paper, three types of Liesegang blocks from sandstone beds of the Hojedk Formation are described. The factors involved in their formation, and their tectonic implication are discussed.
Analysis of fault block movement by the 1995 Kobe earthquake
Horizontal ground displacement associated with the 1995 Kobe earthquake reflects the developmental process of a block mountain under tectonic E-W compression. The focal mechanism of the earthquake is of the strike-slip type. Surface faults specify
the block boundaries. Comparison of the tilting obtained from levelling of benchmarks with the dated marine terraces on one fault block yields a recurrence period of the earthquake of approximately 500 years. The result is in harmony with historical records
A new method for studying clay soils using unaltered soil blocks
The aim of this paper is to outline a procedure for soil block extraction, which is highly appropriate for clay soils. The method described here is rapid and cheap and has been used successfully in clay soils in southern Spain for the last 6 years
. A wooden box is used to shape the soil block in situ and protect it during its transport from the field to the laboratory. Polyurethane foam was selected as the bonding agent, between the wooden framework and the soil block in order to avoid any possible
alterations of the soil. This type of foam is used because it is strong, durable and non-toxic. The polyurethane foam is applied to the soil block as a permanent coating. This technique allows to extract the clay soil solution in the laboratory.
A spectral energetics analysis of atmospheric blocking
The AA. have calculated the evolution of the spectral energetics of two cases of blocking from the winter of 1978-79. The first case occurred over the North Atlantic and the other over the North Pacific. The Atlantic block was forced
by the nonlinear interaction of intense baroclinic cyclone-scale waves with barotropic, ultralong waves. The Pacific blocking resulted from the baroclinic amplificated of planetary-scale waves. In each case the blocking developed downstream of intense intermediate
Rock block monitoring of rapid salt weathering in southern Tunisia
Rectangular blocks of York Stone and of concrete placed on a sodium chloride sabkha in southern Tunisia for six years suffered very severe breakdown, thereby indicating the power of salt weathering as a process in sebkha environments.
Blockierungssituation im europäisch-atlantischen Raum, Teil 1 : Phänomenologische Untersuchungen (Blocking situations in the European-Atlantic region, Part 1 : Phenomenological studies)
The catalogue of blocking situations in the European-Atlantic region presented by Montalto et al (1971) is extended to the period 1951-1983. Inter-annual variations in the frequency of blocking situations show quasi-biennial periods. - (IH)
Block gliding and rheological deformation in the southern Sydney Basin
Study of mechanisms that could explain the widespread gliding of sandstone blocks away from cliffs in the southern Sydney Basin of south-eastern Australia. Highly preferential dip control of the direction of gliding and of the development of benches
over which the blocks move, together with mounds, indicate that the block gliding is due to the rheological deformation of the underlying rock, even though it is a sandy siltstone lacking readily deformable beds. This phenomenon may be a significant
Nature and dynamics of an active block stream, Kunlun pass, Qinghai Province, People's Republic of China
Block stream ; China ; Grain size distribution ; Meltwater ; Mountain ; Periglacial features ; Permafrost ; Qinghai ; Slope dynamics ; Soil moisture ; Soil temperature
This paper describes the results of a five-year study of the physical characteristics and movement of an active rock stream on the north slope of the Kunlun Shan whose thermal regime was previously described. It appears that the surface blocks tend
to slide downslope on the icy surface of the underlying blocks, perhaps aided by water from melting snow. This and the lack of sorting by clast size clearly differentiates them from talus slopes or avalanche deposits.