f Radon transform application to the band-limited gridding of airborne geophysical data

Computer aided two-dimensional data processing, imaging and interpretation almost always require the input data on a square grid. In contrast, the distribution of sampling points in airborne geophysical surveys has almost continuous coverage along the individual flight-lines while the spacing between adjacent flight-lines is almost always larger than is ideal . Therefore, it is essential to reduce such line-based data into square grids. This reduction operation is known as gridding. Taking advantage of the parallel nature of the lines, a so-called bi-directional gridding scheme is widely used in aeromagnetic data gridding. It involves the application of a one-dimensional' interpolation routine twice. The first interpolation is carried out along each original survey line to yield data values at the intersection of each required grid line with the observed line. The second interpolation is then performed perpendicular to the original survey line to produce a value at each required grid node (Geosoft BIGRID, 1990) .