 | | Laying out geophones To investigate a region using seismics, geologists lay out a large number of so-called geophones. The photograph shows preparations being made for the 3D seismic campaign carried out in the Zürcher Weinland in 1997. The survey used a total of 29,000 geophones. (Image: Nagra) Download (1 MB) |
| | | |
 | | Geophone A geophone is a highly sensitive microphone that alters the smallest vibrations in the earth into electric signals. (Image: Nagra) Download (1 MB) |
| | | |
 | | Vibration seismics Seismic waves can be generated using vibrator vehicles where paths and roads are sufficiently stable.(Image: Comet Photoshopping) Download (1.2 MB) |
| | | |
 | | Blasting seismics Seismic waves can be generated by igniting explosive charges placed in shotholes several metres deep. (Image: Nagra) |
| | | |
 | | Drilling shotholes The equipment used to drill the shotholes for blasting seismics is mounted on tractors or small crawler vehicles. (Image: Nagra) |
| | | |
 | | Geophone measurement chain A team laying out a geophone measurement chain in the snow during the 1996 seismic campaign in the Mettau valley, Canton Aargau. (Image: Nagra) Download (1.1 MB) |
| | | |
 | | Seismic image of the rock strata in the Zürcher Weinland 3D seismic measurements were carried out over an area of 50 square kilometres in the Zürcher Weinland. The image shows that the rock layers in most of the area have undergone very little deformation. (Image: Nagra) Download (950 KB) |
| | | |