Magnetic structural information obtained from the HiRES airborne survey of the Isle of Wight

This study summarises the structural information obtained from a modern high resolution magnetic survey over the Isle of Wight corroborated with additional information derived from existing data available over a much wider area. This new, low-altitude, survey offered the opportunity to compare the UK national baseline magnetic data set (GSGB) acquired during the late 1950s and early 1960s with a high resolution airborne geophysical survey (HiRES) data set. The low level modern survey data, covering an unusually small area for an airborne magnetic investigation, has not been systematically de-cultured for non-geological perturbations since the extent of the cultural interference made the task non-viable. However, after spectral filtering of the two data sets, a West to East trending arcuated magnetic basement feature is successfully defined and compared. Depth estimates for this basement feature are proposed and considered alongside previous estimates which placed the causative body at greater depth. Onshore, the low gradient magnetic field, with little significant shallow magnetic structure within a thick succession of sedimentary rocks, is subjected to a range of filtering techniques that permit a preliminary interpretation of lineaments within the succession. This line work is considered in conjunction with the regional fault mapping undertaken as part of a seismic re-interpretation.