The influences of glacier catchments on development of polar coasts
(NW part of Wedel Jarlsbeg Land, Svalbard)
Piotr Zagórski, Piotr Demczuk, Grzegorz Gajek
Institute of Earth Sciences, Maria Curie-Skłodowska University
A glaciated catchment belongs to typical catchments of polar areas. An important role
is played by the glacier - it determines the course of morphogenetic processes, especially the
fluvial ones. The study is based on field research (geomorphological mapping, the
measurements of shoreline range using a GPS receiver) and the analysis of accessible archival
cartographic materials. All the data were compared and processed with the use of GIS
software (ArcView, ArcInfo). The research area includes the coast of Recherche Fiords (NW
part of Wedel Jarlsberg Land, Svalbard). The Recherche Fiord, of meridional course, is
a southeastern branch of Bellsund. Thanks to this, it stays beyond the direct influence of sea
waves that travel eastwards from Greenland Sea into Bellsund. It favours creating coasts of
accumulative character (beaches of the developed profile and flat, abrasive and accumulative
coasts), which constitute over 60% of the Recherche Fiord shoreline. Four catchments,
glaciated to a various extent, have their mouth at the Recherche Fiord. The Scott and
Chamberlin valleys are partially or sparsely filled with glacier ice, while the Renard and
Recherche valleys are nearly fully glaciated.
The catchment as a whole is mainly the source of terrigenic material which is the
result of weathering processes. In the case of glaciated catchments, that material can be
carried and settled down in shoreline zone by glaciers (moraine sediments) or proglacial
waters (sandur fans, wadden). During late Holocene deposition of material with contribution
of glacial processes took place only within the limits of the Renard and Recherche Glacier
catchments. In the zone of the Renard Glacier forefield, three generations of moraines can be
distinguished. The late Little Ice Age has been recorded especially clearly. The terrace I,
where moraine formation occurs as fossil storm ridge, underwent aggradation. While
deglaciation has been proceeding since the end of 19th century, part of ablation moraine
accumulated in front zone influenced the rise of the spit that currently limits Josephbukta
from the east. In the case of the Recherche Glacier, along the east coast of the Recherche
Fiord, moraine sediments were deposited on the terrace I.
The other type of influence of glaciated catchments is connected with delivering
material to shoreline zone through fluvial processes. Dominance of material delivery over
abilities of removing it by waving and dislocating alongside the shore leads to progressive
aggradation of the shore. During the last century, as well as currently, the shoreline zone,
formed by fluvioglacial processes is found directly at the foregrounds of the Renard and
Recherche Glaciers and by the outlets of proglacial rivers from the Scott (Calypsostranda) and
Cramer (Chamberlin valley) glaciers. Intensification of material delivery was the result of
advance of the glaciers during the Little Ice Age followed by quick recession. At the forefield
of those glaciers a few sandur fans of different age can be found. A classic example is the
zone of vast sandur fans of the Recherche Glacier and the Renard one (extramarginal fans).
The location of water outflows were changing due to their progressive recession. Glacial
rivers carried considerable amount of material and deposited it on sandur surface composed of
several layers. Finer material was, and still is, carried directly to the fiord or settled down as
deltas and vast areas of tide flat (wadden) i.e. by the outlet of the Chamberlin Valley.
Nowadays at the foreground of the Recherche and Renard Glaciers, formation of the new
sandur fans is observed and it enters partially into shoreline zone. Older ones, as in the region
of marginal moraines of the Renard Glacier, became inactive as the result of recession. Since
1940s they have only been influenced by marine processes and their surface shrinked by over
1
87 000 m2, becoming the source of material for sections located to the north (Calypsobyen
region) and south (spit in Josephbukta).
Piotr Zagórski,
Department of Geomorphology
ul. Akademicka 19, 20-033 Lublin
piotr.zagorski@poczta.umcs.lublin.pl
Piotr Demczuk,
Department of Geomorphology
ul. Akademicka 19, 20-033 Lublin
demczuk@geomorfologia.umcs.lublin.pl
Grzegorz Gajek
Department of Geology and Lithosphere Conservation
Al. Kraśnicka 2CD, 20-718 Lublin
gajcy@poczta.umcs.lublin.pl
Institute of Earth Sciences
Maria Curie-Skłodowska University
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