Homepage Institut fuer GeophysikHOWTO hide an STS-2


An STS-2 with the adjusting pole towards east. The seismometer is placed on a black gravestone (gabbro) which is part of the shield against air-pressure variations.

STS-2 with cotton wool

The seismometer is wrapped with cotton wool to prevent air convection and thus improve the thermal shielding.

cooking pot

The upper part of the air-pressure shield consist of a large cooking-pot which covers the seismometer. The pot is tightly attached to the gravestone by several screws. There is a seal between both parts.

cooking pot with cotton wool

Again there is some cotton wool wrapped around.

rescue sheet

Finally we use a radiation reflecting rescue sheet to finish the thermal shielding.

Helmholtz cube

As the station is situated within the city we experienced effects from currents induced in the earth by the public tramway. These currents drive magnetic fields which interact with the seismometer. To shield the seismometer from this fields we install a cube of three pairs of Helmholtz-coils. They are driven by an electronic feedback system with a three-component flux-gate as sensor. The flux-gate is missing in this picture but may be seen on top of the station STU seismometer.


STS-1 seismometers are best protected by a  “warp-free plate” and a glass bell which is partially evacuated.  



e-mail: stuadmin@geophys.uni-stuttgart.de