Fróðskaparrit - 01.01.1971, Qupperneq 103

Seismic Measurements on The Faeroe Islands, 1970
111
with 3 seismic channels each and also magnetic tape recording.
The Lennartz equipment is described by Berckhemer (1970).
It is an equipment proved under bad outer conditions and
is used in a modified version also for sea-seismic purposes.
For reflection measurements a 600 m floating cable with
24 traces was used. Hydrophones received the seismic signals
and a 24-channel equipment on »Meteor« registrated these
on photographic paperfilm. Using the two-ship method the
shooting vessel had to follow the end of the floating cable
in a distance of about 200 m. So the reflection equipment
registrated steep-angle refleotions while by the refraction
equipment information of wave velooities was obtained.
The whole programme could be finished within 5 days
(from July 9th to July 14th). Thereby the communication
between the working team on sea and the four landstations was
a faotor of importance. It was not possible to fix a shooting
programme. Information from »Meteor« were transmitted by
shipradio (1.665 MHz) and reoeived by the landstations.
Station 2 was equipped with a radiotelephone (3.150 MHz)
and could be received by »Meteor« without disturbances over
a distance up to 150 km. In addition to these communication
facilities the telegraph station in Tórshavn made it possible
to telephone by radio with »Meteor«.
The Results:
In this publication only the regÍ9trations on land shall be
presented.
Mounting of the seismograms in a traveltime-distance-
diagram gives the possibility to identify seismic events by
applying the method of correlation (analog correlation done
by eye). Fig. 4 shows the mounting for the first part and
Fig. 5 for the second part of Profile 1. In Fig. 6 the signals
from the three shots NE of the islands are shown. The signals
are reproductions of the original seismograms from station 2.
In all three cases the first events could be correlated very
clearly. For the 9hots 9 to 17 of Profile 1 a second arrival