European Center for Geodynamics and Seismology | Centre Européen de Géodynamique et de Séismologie

The Walferdange Underground Laboratory for Geodynamics

The Walferdange Underground Laboratory for Geodynamics (WULG) is located in an gypsum mine (originally exploited by a commercial company).

The sedimentary surface layer above the mine is about 80 meters thick with a distance between the entrance and the old laboratory of 800 meters and the temperature is about 13°C at the end of the mine. This is the ideal place to perform very high precision geophysical measurements.

The mine has hosted the laboratory since 1967 when the first instruments were installed (gravimeters and pendulums). Since that time, many more instruments for geophysics and seismology purposes have been installed.

The advantages of the gypsum mine are:

-stable temperature
-no running water
-low anthropogenic noise level
-easy to access

General technical facilities

Local time basis

The observation of geodynamical time series claims an efficient facility to synchronize the CPU-time of the individual data recorders permanently to Universal Time UTC. For that reason the Walferdange Underground Laboratory for Geodynamics (WULG) has been supplied with a Meinberg NTP TimeServer. The time offsets between that time server and UTC in general don’t exceed 1 Millisecond, in avarage they are at present less than 0.3 Millisecond. A connection of any recorder computer to the time server can be established.

Remote access to recorder computers

Unnecessary local inspections of installed measurement systems should reasonably be avoided. Therefore a remote connection facility allows the access to a recorder computer inside of the WULG from any computer outside of the WULG and enables to control the state of the individual observations permanently from any remote site.

Map of the Walferdange Underground Laboratory for Geodynamics

Mine Entrance
Mine inside

Instrumentation in the mine

The following instruments are installed in the Underground Laboratory:



Gravimeters measures the local gravity (g) of the Earth.

Find out more >



Seismometers records daily worldwide and local earthquakes.

Find out more >



Tiltmeters measures the change in ground slope.

Find out more >

Other instrumentation

GPS Station at ECGS

GPS reference station

The GPS antenna is installed on the roof of the ECGS office. The real-time acquired GPS-data is automatically transfered to the Administration du Cadastre et de la Topographie, Luxembourg.