NTBs 1983 – 1984

Technischer Bericht NTB 84-14

Abstract

In the framework of the geophysical investigations of NAGRA in Northern Switzerland the Swiss Geophyiscal Commission has surveyed a total of 6'250 km of aeromagnetic lines at two different flight levels. Furthermore, a ground-magnetic pilot programme comprising 1'480 stations was carried out in the Hornussen area.

The aeromagnetic data are presented on a series of maps. They show no anomalies that allow a determination of the depth to the crystalline basement and of the Permocarboniferous through embedded therein. A modelling study has shown that this phenomena can be explained by the small susceptibility contrasts between sediments and crystalline rocks as determined on core samples.

The ground-magnetic investigations do not allow an interpretation as all mapped anomalies had to be attributed to man-made sources.