3D Goussev filter—a signal separation and edge detection filter applied to aeromagnetic data in the Great Australian Bight

Abstract

A phase of image processing usually precedes the initial stages of any interpretation project. With aeromagnetic data, this image processing involves the construction of a variety of derivative grids of the total magnetic intensity data to enhance the magnetic signal and make it ready for interpretation. Routinely, the reduction-to-the-pole (RTP) transform is performed on the total magnetic intensity (TMI) data and then the first and, possibly, second vertical derivative calculations to enhance the magnetic signal. The first vertical derivative (1VD) of the RTP data is the most common derivative filter to enhance the magnetic signal to allow anomalies generated by structure and boundaries to become more evident. The tilt derivative is an excellent edge-detection filter (Miller and Singh, 1994; Fairhead et al., 2004). The Goussev filter (Goussev et al., 1998, 2003; Nabighian et al., 2005) provides high signal-to-noise ratio and high lateral resolution of magnetic anomalies from different types of structural discontinuities. These more complex filters are often applied on aeromagnetic data to produce enhanced imagery for interpretation and then compared to the RTP 1VD grid to see where they can add value to the interpretation process.