Geological Interpretation of Turbidity Marine Channels using 3D Seismic Data

Abstract

The following report explains the Geological Interpretation of turbidity marine channels environment using 3D Seismic data and the characterisation of different channel features from Block 34 offshore Angola. The 3D seismic data allow turbidity internal channel architectures to be recognized and mapped. Therefore to develop a geological interpretation of deep marine channel system was necessary a combination of surface horizons maps, seismic attributes such as RMS amplitudes maps, and Geobodies channels extraction for better understanding of turbidity channels architecture and geomorphology.

The application of 3D seismic data techniques showed evidences of turbidity channels by following important steps such as: Horizons interpretation, surface horizons maps extractions, RMS amplitude maps and Geobodies channel extraction. In this way, the horizon map extractions were done by first interpreting four horizons A, B, C and D respectively that comprises three channels systems between Oligocene to Miocene interval in age from 2070 m to 3100 m depth approximately. Secondary RMS amplitude maps were generated to isolate the geological characteristics from background features by amplitude response on a map view. Such maps displayed an individualization of high amplitude values that can be interpreted as sand channel fill. For each channel system, were generated six RMS amplitude map levels, whereas seven Geobodies in total were extracted for the three systems. Finally, Geobody channels extractions were generated to identify, isolate, and extract turbidity channels seen on seismic data in a three dimensional perspectives and consequently Bulk volume of the channel. From this bulk volume data, was possible to do volumetric estimations of potential STOOIP and calculate the recovery factor volume by utilizing near oil field deep water data.