In the Southern North Sea, 3D seismic data had been widely acquired to explore for hydrocarbons, but interpretations of these datasets until now focus mainly on the deep exploration targets of the petroleum companies. Less attention is given to shallow sediments. But these sediments often contain channels that can serve as efficient stratigraphic traps for shallow gas. Thus the mapping and identification of these shallow channels and defining their infill lithology is important considering the abundance of shallow gas and its significance both as a ressource and hazard. In this study, seismic spectral decomposition technique has been used to delineate shallow thin channel geometry in a 3D seismic data acquired in the Dutch sector of the North Sea. The concurrent interpretation of curvature and coherence cubes with seismic facies analysis based on reflection terminations and geometry, amplitude and continuity enables the discrimination between shale versus sand filled channels. The results of the spectral decomposition show two distinct low sinuosity channel features in NNE-SSW direction but becomes diffuse towards the North. The strong negative curvature anomaly along the channels axes observed in the most negative curvature attribute implies that the sediments within the channels have undergone more compaction. These strong negative curvature anomalies are interpreted to be due to differential compaction of shale filled non productive channels.

9In the Southern North Sea, 3D seismic data had been widely acquired to explore for hydrocarbons, but 10 interpretations of these datasets until now focus mainly on the deep exploration targets of the petroleum 11 companies. Less attention is given to shallow sediments. But these sediments often contain channels that can 12 serve as potential reservoir units. Thus the mapping and identification of these shallow channels and defining 13 their infill lithology is important. In this study, seismic spectral decomposition technique has been used to 14 delineate shallow thin channel geometry in a 3D seismic data acquired in the Dutch sector of the North Sea. The Copyright Staement 25We have read and understood the licence and copyright terms and wish to state that we agree 26 with the terms and conditions. Nonlin. Processes Geophys. Discuss., https://doi

A knowledge of sedimentary thickness and basement depths of a basin is necessary in understanding the structural set up of formations and evaluation of the hydrocarbon potentials of a region. In this work aeromagnetic data, obtained from the Nigerian Geological Survey Agency (NGSA) Abuja, has been interpreted to obtain sedimentary thickness, structural faults and intrusions including the basement depths of the eastern Niger Delta, Nigeria with the implications for hydrocarbon prospecting. Results from magnetic attribute analysis, total horizontal derivative operations, spectral analysis and source parameter imaging reveal the following: the study area is magnetically heterogeneous; the magnetic intensities range for the region is from – 46.2 nT to 160.3 nT, with residual magnetic intensity values of -15 nT to 13 nT revealing sediments with low magnetic rocks in the southwestern and southeastern parts of the study area and magnetic rocks and basement intrusions in the northwestern, northeastern and central parts of the study area; sedimentary thickness range from 96.5 m to 6601.5 m hosting faulted anticline and syncline structural bodies good enough for hydrocarbon formation and trapping and a maximum depth to basement of 6601.5 m. The sedimentary thickness and structural types, influenced by the basement intrusions, make the region a hydrocarbon potential area and it is recommended that prospecting in the southern and northern parts of the study area should be intensified.

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