Geotomographie - Model DDS - Dual Downhole System - Brochure

The Dual Downhole System (DDS) is used to receive P- and S-waves in dry and water lled boreholes in order to determine interval velocities. The e DDS consists of two stations each equipped with tri-axial sensors. The e stations are mechanically connected to each other to ensure the alignment of all horizontal sensors. Both stations are coupled to the borehole wall by a pneumatic clamping system (inatable bladder). Air is supplied to the DDS through an electro-pneumatic hybrid cable with a Kevlar tension string. A magnetic compass shows azimuthal deviation to North and can be used to get the orientation of the DDS in the borehole. The cable is terminated by a connector to the seismograph.