Frequency Decomposition Methods Applied to Synthetic Models of the Hermod Submarine Fan System in the North Sea

Abstract

Frequency decomposition methods have been applied to a seismic dataset which images the late Palaeocene Hermod Fm. submarine fan system which occurs within the Viking Graben in the Northern North Sea. Conventional bandpass decomposition methods are compared to HD frequency decomposition – a technique based on matching pursuit of wavelets and the sensitivities of each method are discussed. Red-Green-Blue colour blending is shown to image in great detail channels, levees and splays. In order to understand the controlling factors determining the colour, contrast and amplitude shown in the RGB blends produced using each decomposition method, synthetic models of a Hermod splay has been produced. Within these models thickness and acoustic impedance are varied to investigate which has a larger effect. Frequency decomposition and blending of the synthetic models closely resembles blends created from the original data and it is likely that thickness changes, within the Hermod fan, which varies from above the tuning thickness in the channel core, to below tuning in the distal splays is mainly responsible for colour, amplitude and constrast changes within the blends.