Seismic Imaging Explortion (SIE) and simultaneous source acquisition technologies to support the exploration, appraisal and development of oil and gas formations.
Seismic data provides the most important lens into the sub-surface. It allows for reservoir rock structure vision, detects where hydrocarbon potential may lie and can also be used to detect reservoir changes during oil and gas production.
Until recently, discovering oil and gas beneath thousands of metres of the earth’s landed surface has been limited to the monadic deployment of trucks carrying seismic data acquiaition machinery to ensure that there is no interference with seismic signals. These signals are reflected from formations within the earth’s substrata and collected by receivers (geophones) for analysis to indicate the whereabouts of natural resources.
Today, SIE technology allows for runs of multiple seismic imaging trucks, which collect 3D data simultaneously and use technology to process out any interference (multiple data collection noise) upon analysis. This effectively both speeds up exploration by cutting survey times by up to 80%, thereby lowering costs, and reduces environmental attrition through the use of cable-less geophones or “nodes”.
Nodes are small cylindrical boxes (approx. 15x12cm in size and weighing 2.5kg), are internally powered (Li-Ion battery) and comprise an internal geophone receiver, GPS positioner and built-in memory. Positioned at 25m intervals in lines 100m apart, they are buried just below ground level and covered with a few centimetres of earth. Easy to install, the nodes allow for the minimal cutting of vegetation and disturbance to wildlife and once used are simply collected with minimal fuss.
Energy sources are deployed along lines perpendicular to the receiver lines (see dia. below) and send signals through a vibrating steel plate pressed to the ground. This cable-less seismic system is a high performance, low impact surveying method ideally suited to work in sensitive environments. It produces quick results with less manpower and fewer supporting vehicles. Optimum coverage and quality is achieved without deploying kilometeres of cables, so achieving limited impact on wildlife and vegetation buy comparison to other techniques.
As a resut of adopting simultaneous source acquisition technology to map structures, up to 60% cost savings can be achieved and further clarity in drill positionings can be attained. Careful planning can see a ten-fold increase in productivity, meaning the acquirisition of higher quality images in significantly less time than conventional methods.