ABSTRACTS / RESUMES - Comitato Glaciologico Italiano

stributed. The lower terraces show good continuity standing
2 to 20 meters above the present river bed. Salix
and/or Alnus younger than 60 years on these terraces indicates
that the valley filling occurred in this event.
The size of blocks is about 2.5 meters and the downstream
change of it is small in the headwater of the Tedori river. It
abruptly increases at about 1 kilometer downstream from
the confluence of the Miyadani river which is one of the
tributaries of the upper Tedori river. From there it decreases
downstream along the river. Many landslides occurred
during the two days rainstorm. The Miyadani river basin
also experienced many landslides. The deposits of a landslide,
which locates about 4 kilometers upstream from the
junction of the upper Tedori river, consist of many huge
blocks larger than 2 meters. These deposits are distributed
both sides of the river and there are sorted fluvial sediments
upstream behind the deposits. These indicate that
the landslide dammed up the Miyadani river and that the
destruction of the dam caused the event. The large hydraulic
bore washed away the blocks, from which the landslide
dam had been made and which were picked up from the
river bed. Thus, these were transported along the Miyadani
river and the upper Tedori river by debris flow of dam
failure origin. The landslide dam was estimated about 30
meters in height and about 60 meters in width based on
the valley morphology and distribution of deposits. Because
there were no lake formed by landslide dams in the uppet
Tedori river basin after the event, immediately after
the dam forming the dam was destroyed. On the higher
terraces along the upper Tedori river, which was formed
before this event, there are huge blocks larger than 5 meters.
The slope of this terrace surface is as same as the present
river bed. This suggests that the debris transport caused
by the debris flow of the dam failure origin were repeated
along the upper Tedori river.
Some other Japanese mountain rivers have also experienced
such catastrophic debris transport caused by failure of
landslide dams. This type of debris transport process is
very important along the Japanese mountain rivers.
NICK A. SHISHONOK 1 & VALENTIN M. YATSUKHNO- 2
Morphometry and genetic-age features
of glacial landformes: problems of interrelation
1 Geological Sciences Institute, Belarus Academy of Sciences,
Zhodinskaya st. 7,220141, Minsk, Belarus
2 Geographic Department, Belarussian State University,
F. Skoryna avo 4, 220050, Minsk, Belarus
The territory of the Republic of Belarus presents an example
of classical forms of the glacial landforms. The use of the
morphometric method enables one to identify its genetic,
age features and hence to determine the duration of landformes
tramsformations under the effect of later processes.
The differences in morphology of the landform types in
Belarus are quite obvious. To illustrate, marginal glacial
352
formations are characterized by maximum absolute points,
by considerable variations in relative heights (mainly 20­
35 m), slope steepness of 10-20° and more, predominance
of ridge-undulating landforms. On the contrary, lacustrine-alluvial
and alluvial plains are very weakly dissected:
dissection depth of 2-5 m/km'; dissection density up to 0,5
km/km'; slope steepness of 1-3°. These plain and rolling
plain sites are occasionally complicated by eolian hills. In a
quantitative sense, moraine, outwash amd lacustrine-glacial
types of landforms hold an intermediate position between
marginal landforms and alluvial plains.
As a result of previous investigations, it has been found
that 5 glaciations had covered the whole territory of Belarus,
and the greatest effect on the land surface was exerted
by the Dnieper (240,000 years ago), Sozh (140,000 years
ago) and the Lake Region (70,000 years ago) glaciations. It
should be noted that the landforms within each zone of
glaciation are distinguished quantitatively. Glacial forms of
the Sozh Ice Age are caracterized by the greatest absolute
and relative height, rather long (up to 500-800 m) slopes.
The landforms of the Lake-Region Ice Age are distinguished
for intensive manifestations of denudation processes,
for considerable steepness, short slopes, high extent of hilliness.
The landforms of the Dnieper Ice Age are heavily
denuded and exhibit a wide-undulating character of the
spatial manifestations. The like patterns of morphometric
parameters distribution are revealed within the glaciation
stages as well. The quantitative differences therewith demonstrate
that at every subsequent stage of its development
the glacier is less active than at the previous one.
Thus, the Pleistocene inland ice retreation after from the
territory of Belarus, various glacial, stadial and phasal formations
were left behind which differ in their morphometric
characteristics.
YAVOR Y. SHOPOV\ L.T.TsANKOV\ M.E. SANAMBRIA\
S. GEORGIEV 2
, AL. BENDEREV\ D.C. FORD\
J. LUNDBERG 5 , A.].T. JULL 6, L.N. GEORGIEv l & R. DUKOV 7
Quantitative reconstructions of variations
of karst denudation rates during the last 1 Myrs
1Faculty of Physics,Sofia University, James Baucher 5,
Sofia 1164, Bulgaria
2 Bulgarian Agriculture Academy, Sofia, Bulgaria
3 Institute of Geology, Bulgarian Academy of Sciences,
Sofia 1000, Bulgaria
4 Geography Department, McMaster University Hamilton,
Ottawa, L8S 1K4, Canada
5 Geography Department, Carleton University, Ottawa, Canada
6 AMS Facility, University of Arizona, Tucson, Arizona, USA
7 Bulgarian Hydro-metheorological Survey,
Bulgarian Academy of Sciences, Bulgaria
We used the quantitative theory of solubility of karst rocks
(Shopov & alii, 1989,1991) in dependence of the tempera-