ABSTRACTS / RESUMES - Comitato Glaciologico Italiano

lowed any more and problems arose. New cross-country
connections between settlements were needed and old natural
corridors did not provide these roads. Road constructors
could save a lot in building and maintenance costs if
the geomorphic facts were considered. The examples in
this presentation are from Finland where road construction
is very expensive because the severe winters need
well-based roads In Finland we have more roads crossing
the Arctic Circle than the whole North America and they
are paved. This paper gives examples of geomorphic elements
effecting on road construction in cold environments:
eskers, drumlins, late and postglacial glaciolacustrine
and marine sediment plains, mires, steep rock cliffs, river
channels and ice-darns, fluvial erosion, palsas, and how
to solve problems in these connections. Frost sensible materials
have to be removed and replaced by more favorable
sediments because road surfaces are kept snowfee in the
winter time and their bodies are therefore exposed for
deep freezing The maintenance of roads can be supported
with some solutions affecting on snow drift and icing problems
and avoiding the geomorphic factors causing the
problems and using the natural processes to help people.
At the end shall be given some examples how the road
constructions are affected the geomorphic processes and
vice versa. For example bridges dam moving river ice and
road banks cause in special occasions icing.
LEONID R. SEREBRYANNY
Moraines of mountain glaciers:
results of integrated glaciomorphological
and glaciosedimentological investigations
Institute of Geography, Russian Academy of Science,
29 Staromonetny, Moscou 109017, Russia
The integrated glaciomorphological and glaciosedimentological
approach stimulates the analysis of mechanisms of
moraine formation as a result of interaction between glacier
and its bed. Much attention is given to the estimation
of possibilities displayed by glaciological interpretation of
the quantitative analytical data about moraine composition
and structure (morphometry, morphoscopy, grain size
analysis, stone and mineral counts, X-rays analysis) . Proceeding
from this keystone position, the sources of debris
supplied to glacier systems are identified and the mechanisms
of sediment mobilization and transportation as well as
accumulation processes are thoroughly studied.
The development of actual models of moraine formation is
proposed for several glacial mountain regions (Central
Caucasus, Central Tien Shan, Spitsbergen). As a result some
classical ideas on the moraine formation in mountains
were revised. Marginal moraines are formed during glacier
advances and consist mainly of plucking and attrition products
of glacier bed. Very often it is possible to distinguish
also assimilated till materials of the former stages of glacier
evolution as well as incorporated pockets of fluvioglacial
sediments.
Lateral moraines are complex polygenetic landforms created
predominantly during glacier advances and paragenetically
connected with stadial marginal moraines. They consist
usually of the same products eroded and transported
from glacier bed. During glacier retreat stages the supply
of such sediments weakens and slope materials are accumulated
in lateral moraines.
Special reference is devoted to the superficial moraines of
mountain glaciers. Different types of these forms are analysed.
All of them have small thickness and are attached to
uppermost parts of glaciers. They have a subordinate importance
in the structure of glacial morphosculpture of
mountain regions. Taken as a whole, the structure of
mountain glacial formation looks like a result of active impact
of glaciers upon their beds.
ENRIQUE SERRANO 1
& JERONIMO LOPEZ-MARTfNEZ 2
Periglacial landforms and permafrost distribution
in the South Shetland Islands
1 Departamento Geografia, Urbanismo y Ordenacion del Territorio,
Universidad de Cantabria, Avda. de los Castros sin.39005 Santander, Spain
2 Departamento Quimica Agricola, Geologfa y Geoqufmica, Facultad
de Ciencias, Universidad Aut6noma de Madrid, 28049 Madrid, Spain
Periglacial landforms occupy a little area in the South Shetland
Islands due to the large ice coverage (>90 0/0).
Although periglacial landforms are only present in the 3 %
of the archipelago's area, they represent about 30-50% of
the ice-free terrains, and correspond to some of the richest
and most varied ecosystems from the South Shetland
Islands. The periglacial landscape is overprinted on the
existing glacial landforms and on the raised beaches and
marine erosive platforms at different altitudes, where permafrost
is also common. The periglacial landforms and
processes are conditioned by the cold and humid climate
of the maritime Antarctica, that facilitates a wide availability
of liquid water during summer time, when average
temperatures are higher than O°C.
The distribution of the periglacial landforms and processes
has been studied by means of geomorphological mapping
in nine of the larger and more significant ice-free areas of
the archipelago. The places and scales of the geomorphological
maps are: Deception Island (E. 1:25.000); Byers Peninsula
(E. 1:25.000), Hurd Peninsula (E. 1:5,000 to
1:25.000), Williams Point (E. 1:10.000), Renier Point (E.
1:10.000) and Barnard Point (E. 1:10.000) in Livingston
Island; Half Moon Island (E. 1:10.000); Coppermine Peninsula
(E. 1:10.000) in Robert Island and Fildes Peninsula
(E. 1:15.000) in King George Island. These maps have allowed
the inventory and the surface and altitude distribu-
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