Magnetic Gradient Arrays for Marine UXO Surveys – Change is good!

Join Nigel Halsall, Solutions Consultant at Geosoft, for his presentation Magnetic Gradient Arrays for Marine UXO Surveys – Change is good! during the EAGE Near Surface Geoscience 2016.

Session Details

Second Applied Shallow Marine Geophysics Conference
Environmental Applications and Non-seismic Methods I
Abstract Number: We ASM 03
Charimen: M.E. Vardy - National Oceanography Centre & L.R. Stensen - Statoil ASA

Talk Summary

Magnetic gradient surveys measure the rate of change of the earth's magnetic field between two or more locations. In this paper we demonstrate benefits of collecting and using magnetic gradient data for locating ferrous targets such as unexploded ordnance (UXO) or explosive remnants of war (ERW) in marine environments, with the aim to reduce costs and provide quality survey results. The incremental survey cost is very reasonable to add multiple sensors to a single sensor survey system, thus creating gradient arrays with several sensors. Benefits of such array systems include maximising coverage of the survey area, more reliable target or anomaly picking and improved modelling and analysis of targets. In areas with sparse survey coverage, gradient array data can yield more accurate target location information than single sensor data. Using gradient array data yields superior results and higher confidence in the geophysical interpretation. This helps to reduce the number of anomalies or targets that are potential UXO and need to be investigated, saving significant time and money.

Authors: Darren Mortimer, Nigel Halsall and Nick Valleau