Greinar (Vísindafélag Íslendinga) - 01.01.1951, Page 45

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—15 mgal. in the center of the country. This interesting
general picture remains quite uninfluenced by the poss-
ible errors.
The main result of our studies is thus, as shown in
the isogal diagram where all gravity stations are
indicated by small circles, that the Bouguer anomaly is
about +50 to +55 mgals. along the southwest coast and
decreases rather regularly toward the northeast as far as
the center of the country.(!)
The measurements of Ansel and Schleusener in north-
east Iceland show, on the other hand, a positive Bouguer
anomaly of 10 to 20 mgals. so that the values decrease
both from the north and south toward the center. The
general picture would appear to be that of a 60—70 mgal.
deep gravity bowl. As it is intended to extend the measure-
ments soon a further discussion of the results will be
postponed.
Besides the general tendency in the Bouguer anomalies
the measurements reveal important local anomalies. At
Kotströnd in ölfus, a fault line produces an anomaly of
8 mgals. The Bouguer anomaly decreases by 17 mgals.
on a 10 km. line running from Selfoss to Sog. The Thing-
vellir graben is marked by a conspicuous gravity ano-
maly. At several other places there are also significant
anomalies. But the points are, however, still far too few
to give a reliable basis for a thorough discussion and inter-
pretation.
The detailed results of our measurements and reductions
are given in the following table.
The work of the French scientists was voluntary and
the only costs were therefore traveling expenses, which
were provided by:
(1) It must be stated that a revision of the gravity reductions
which was done after preparation of the map, revealed small errors
in three points in the area south of Tungnaá river. But due to the