the Expedition ARKTIS-XIX/4 of the research vessel POLARSTERN ...

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Summary of results
The summit plateaus of the mountain range on Store Koldewey is covered by rocks
dominantly of local material weathered to different degrees. On all the summits
erratic material is occurring as smaller boulders from which no one was large enough
to sample for SED. The erratic material is represented by white, red and purple
quartzites. On the edges of the plateau scattered outcrops of bedrock occur. In the
U-shaped valleys which intersect the plateau mountains glacial striae were observed,
with a direction of c. 70°. On the ice scoured northern part of the island glacial striae
have a direction of 96° and 104°.
Both the area east of the plateau mountains and the southern lowland are covered by
a ground moraine containing of the local gneisses and quartzite boulders. On the
ground surface stone rings and other freeze-and-thaw features were observed. On
the west coast of the island a series of accentuated moraine ridges were observed
an a height of c. 100 m a.s.l. The freshness of these ridges suggests a Holocene
age.
6.6 Onshore marine deposits
O. Bennike
In connection with the lake coring programme carried out during the ARK XIX/4
expedition, the opportunity arose to do some work on the raised marine and littoral
deposits in the areas visited. Pre-Holocene deposits were found on Store Koldewey
in 1907, but have not been revisited since then, and no Holocene marine deposits
had been located on this island. Northeastern Geographical Society Ø was visited by
Quaternary geologists more than 30 years ago, but few details from this investigation
have been published (Funder & Hjort 1973, Hjort 1979, 1981).
Pliocene (?) sediments on Store Koldewey
Already in 1907 during the Danmark Ekspedition, shell bearing deposits were found
above the Jurassic sediments on Store Koldewey. A few years later the shell fauna
was described by the Danish zoologists Adolf Jensen. Eight species could be
identified, and the fauna could be characterized as a high arctic fauna similar to that
living in the region at the present. All species are extant, and Jensen considered the
fauna of Quaternary age. However, the deposit was found at around 120 m a.s.l.,
much higher than any other shell bearing Quaternary deposit known from East
Greenland at that time.
In the 1970’s some of the shells were submitted for radiocarbon dating, yielding a
non-finite age (>40 000 years BP, Lu-930, Hjort 1981). The Store Koldewey fauna
shows some similarity to that from the Pliocene Kap København Formation in North
Greenland. However, it was not until 2003 that the chance arose to revisit the Store
Koldewey deposits.
During the summer it was found that the Pliocene (?) sediments could be followed for
about 30 km along the east coast of Store Koldewey. The deposits are everywhere