Color Blending On Spectral Decomposition Method For Delineating Geological Features

Erlangga, Garda; Swastiraras, Yan F.; Afafa, Kahvi

A research using spectral decomposition method has been carried out to locate subsurface geological features in block F3 Offshore field, in Northsea region, Netherland. Seismic section being analyzed is post-stack time migration data. This research start by picked a horizon which cut a bright spot in inline 250. The reason of choosing the horizon that cut the bright spot is usually bright spot indicates the existence of hydrocarbon and commonly associated with interesting geological features such as hydrocarbon trap, fault, and channel which is a hydrocarbon reservoir. Then a spectral decomposition is done on the horizon slice to transform from time domain into frequency domain.

The last, RGB color blending as development of spectral decomposition was performed to see the response from surface of horizon slice toward three different frequencies to get better picture of geological features. Frequencies which have been choosen as the representative of color blending are 15 Hz, 30 Hz, and 60 Hz. The simple concept of color blending is that light is a composition of many colors and represents certain frequency of electromagnetic wave.

Geological features such as major fault, minor fault, meandering channel, and hydrocarbon trap are seen in the result of the color blending.More over, the result also shown that CWT is better than FFT to see geological feature, because CWT can follow the change of time function and produce good frequency resolution in non-stationer signal.

AAPG Search and Discovery Article #90163©2013AAPG 2013 Annual Convention and Exhibition, Pittsburgh, Pennsylvania, May 19-22, 2013