Aeromagnetic investigation of sedimentary thickness along argungu north western Nigeria

In this study, we investigated sediment thickness along Argungu North Western Nigeria. Sediment thickness varies on a regional scale. It's generally thicker and larger grained near the coasts and thinner and finer grained further out to sea. But ocean currents and seafloor topography (bathymetry) play a role in sediment thickness as well. We conducted forward modeling of receiver function using different thickness of low velocity sediment layers. We varied low velocity layer from 0 - 4 km thickness. We applied Gaussian width parameter of 1.5 and 2.5, which corresponds to low pass filter with a corner frequency of 0.75 and 1.25 Hz, respectively. In this numerical analysis, we applied halfspace model with low velocity layer near the surface representing sedimentary layer. We generated synthetic receiver function using Thomson-Haskell matrix method. From our modelling, changes occur in the first few seconds of calculated synthetic receiver functions. Such changes occur due to reverberation in the sedimentary layer near the surface. Such changes differ with different sedimentary thickness used in the model. We applied H-k stacking method to the calculated synthetic receiver functions to see the effect of sedimentary layers to the results of H-k stacking.