Studies of marine CSEM responses from geological model of Niger Delta hydrocarbon province using multi-components 2.5D finite element forward modeling are very helpful to determine suitable parameters for marine CSEM survey in the area.The models consist of three resistive hydrocarbon layers,two of which overlain each other.This presents an opportunity to study and understand the marine CSEM responses from two vertically placed resistive layers.Forward modelling result shows that electric field amplitude measured when transmitted EM waves interacted with two resistive layers directly overlying each other,is higher in magnitude than measured electric signal from the individual layer.Two sets of frequencies were used comprising the standard frequency (0.25 Hz) and the upper (0.75 Hz and 1.75 Hz) and lower (0.125 and 0.05 Hz) frequency harmonics.Lower frequency harmonic (0.05 Hz) were found to produce high amplitude signal over a long receiver separation displayed as magnitude versus offset (MVO),but show low percentage anomaly,computed as Normalized Amplitude Ratio (NAR),compared to 0.25 Hz and the upper harmonics.This makes it fit for targets buried deeper beneath the seafloor,while 0.25 Hz frequency and the upper frequency harmonic would be veritable choice for target buried at medium and near seafloor respectively.Thus,a wide range of frequency may be needed to explore for oil in this region owing to its wide range of depths.