Fróðskaparrit - 01.01.1975, Page 95

Glacial Erratics
103
From station 63 and onward we used a home-made tube
sampler with a diameter of 5 centimeters mounted below the
front opening of the dredge (fig. 1) for picking up the finer
material. These samples will not be described in the present
paper.
Geological setting
The Faeroe Island are the erosional remnants of a basaltic
lava plateau of Lower Tertiary age. The visible part of the
lava pile has a total thickness of about 3000 meters and
consists of aphyric, plagioclase-phyric and olivine-phyric
tholeiitic lavas and intercalated thin tuffaceous beds (Rasmus-
sen.and Noe-Nygaard 1970). It is divided into a lower, middle
and upper series separated by small angular unconformities.
The lower unconformity is marked by a thin coal-bearing
sequence, the upper one by sill intrusions. The lava pile is
slightly deformed into two structural domes, one centered just
north-west of the islands and trending in the direction east-
north-east to west-south-west, the other centered just west of
the southernmost island, Suðuroy, and trending in the direction
north-north-west to south-south-east. The basaltic lavas
probably rest on a continental crust 30 kilometers or more
thick (Bott et al. 1974).
On the outer part of the broad shelf south-east of the
islands (fig. 2) the basalts give way to a sedimentary basin
marked by a gravity low (Bott and Watts 1971). The total
thickness of the sediments is about two kilometers between
Sandoy Bank and Suðuroy Bank according to a seismic re-
fiection profile. The sediments are prograding towards the
south-east and are probably younger than the Faeroe basaltic
plateau (Korsakov 1974). The steep inner margin of the basin
coincides with the innermost part of the trough between the
two banks. It runs in roughly the direction north-north-east
to south-south-west judging from an aeromagnetic map {Avery
et. al. 1968). Towards the south-east the basin is separated by