Photo: COWI

Operational setup 

COWI's concept for standard configuration has been developed as a cost-effective solution for conducting high-resolution shallow seismic investigations with a high production rate on roads.

Standard configuration

The standard setup consists of the Minibuggy dragging a 200 metre long array of geophones behind it on a paved road or a relatively level dirt road. The vibrator is affixed to the center of the vehicle controlled by a computer within the cab.

The drag cable is equipped with 95 gimbaled geophones separated every 1.25 metres the first 50 metres behind the vibration source and every 2.5 metres the remaining 150 metres along the cable.

The denser sensor spacing near the vibrator produces high quality data in the shallowest portion of the near-surface. The 200 metre offset provides high-resolution data at depths of more than a kilometer.

Operation

The system requires only two personnel to operate. A qualified operator runs the Minibuggy, vibrator and seismic acquisition system. A field assistant ensures the cable is in the optimal configuration during operation.

The dragged land streamer configuration is constructed for cost-effective investigations on paved roads where easy access and long straight sections facilitate high daily production rates. Production rates vary according to local conditions, however, average rates are 2 kilometres per day.