Observations on Some Holocene Glacier Fluctuations in West Greenland.
Anker Weidick. Reitzel, 1968
Abstract
HistoricaI and contemporary data record a major fluctuation of the position
of the Inland Ice and local glaciation ice margins in the area. Regardless of the
glacier type these frontal fluctuations are mostly in phase, with glacial readvances
occurring around 1650(?), 1750(?), 1850(?), 1890 and 1920 A.D. Correlation with
meteorological data suggests the operation of a delay of a few to twenty years before
glacier response to climatic fluctuation. Whilst the individual readvances generally are
recognisable throughout the area their magnitude shows a regional variation. Thus,
near the coast and in South Greenland the readvances before 1850 produced the
historicaI maximum extent of glaciers, whilst in the northernmost part of the area,
Nugssuaq peninsula and Umanak district, the advance of 1920 in part was responsibIe for the maximum extent. The historicaI frontal fluctuation corresponded with
a fluctuation of the glaciation limits of 100-200 m.
As a whole the deposits of the historicaI glacier advance form a zone marking
a single stage in the extent of the glaciers. Zones of Inland Ice margin deposits of a similar magnitude of prehistoric age, have been widely recognized in the area. Three zones have been distinguished; an inner zone, an outer zone and a nunatak zone. The
inner zone possibly includes several stages, but the main features date from subboreal or early subatlantic times. The outer zone comprises two stages formed at
7,500-8,500 and 9,000-9,500 B.P., whilst the nunatak zone (comprising several
stages) was formed before or around 10,000 B.P.
Prehistoric ice margin stages of local glaciers have been less extensively investigated. In general, they indicate only late and slight development of local glaciers due, it is believed, to the glaciation limit at the time of the retreat of the continental glaciation being aIready too high for their widespread development. An exception from this general trend is in the Julianehåb district where the more rapid
disappearance of the continental glaciers may have favoured the better development of local glaciers.
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