New Airborne Survey Technology
Airborne geophysical surveying is a process of measuring the variation in several key physical or geochemical parameters of the Earth. The most important parameters measured are conductivity, magnetic susceptibility, density, and radioactive element concentration. Any change in the Earth's near-surface that causes a measurable change in these parameters presents a potential application for airborne geophysics.
Since 2000 CGG has been offering high-end airborne survey capability through the global merger of the leading airborne geophysical survey companies, which then joined the CGG group in 2013. CGG’s new time-domain electromagnetic solution maps shallow to deep geology in one pass. Multipulse (bottom section) combines Tempest's (top section) near-surface resolution and Geotem's (middle section) greater depth of exploration. CGG’s Multipulse, is an innovative near-surface and deep-penetrating electromagnetic (EM) survey technique, which increases resolution and bandwidth in exploration activities.
The new technology combines the benefits of CGG’s airborne time-domain EM products, Helitem, Geotem, Megatem and Tempest by offering a high-power pulse (half-sine wave) for depth of exploration and a lower-power pulse (square wave) for near-surface resolution, both within one cycle, providing the value of two exploration techniques in one pass. The system allows for enhanced definition of near-surface layers such as palaeochannel mapping, oil sands and regolith characterisation for engineering applications as well as in mineral exploration for low-conductivity targets such as porphyry deposits, sedimentary exhalative deposits (SEDEX), volcanic-associated massive sulphide (VMS) and Mississippi Valley type (MVT) deposits.
Multipulse technology can be applied on CGG fixed-wing or helicopter time-domain systems, offering maximum spatial resolution and what promises to bea cost-effective option for regional projects. Benoît Ribadeau-Dumas, senior executive vice president of CGG’s Acquisition Division, said: “CGG has launched Multipulse as a response to industry demand for airborne time-domain EM systems to achieve higher-resolution geological mapping and more effective mineral exploration results."