Land Gravity

For land gravity surveys, Excel owns and operates Model-G LaCoste and Romberg gravity meters as well as ZLS micro-Gal Burris meters. The LaCoste and Romberg gravity meters have an absolute accuracy of ± 0.01 mGal and a repeatability ± 0.02 mGal. The ZLS micro-Gal Burris meter has an absolute accuracy of ± 0.001 mGal and a repeatability ± 0.005 mGal. Land gravity surveys are implemented as a non-destructive cost effective geophysical technique used to evaluate large areas, assess environmentally sensitive regions, resolve seismic- result ambiguities and carefully target seismic-line placement.

 

During the past five years alone, Excel has acquired over 30,000 land gravity stations on major projects in North America, Iraq and Gabon. Land gravity surveys are usually conducted on foot using a small light weight gravity meter carried on the back of an operator. However, other appropriate ground transportation can be used to reduce travel time between stations. Excel uses state of the art GPS technology on gravity surveys to allow for larger data coverage performed in a quick and cost effective manner.

 

Ground gravity surveys have proven to be an excellent tool for identifying anomalies of interest for the oil and gas exploration, mining and environmental industries. Excel has designed several land gravity surveys for major clients worldwide identifying targets such as fault locations, salt dome geometries, near surface anomalies caused by waste dumps as well as locating buried mine shafts. The resulting datasets are then modelled using proprietary 2D and 3D gravity modeling software and integrated with other existing geophysical data, well information and surface geology. Variable density terrain correction techniques are also used for areas of complex geology.