Abstract: The mathematics governing most of the data processing operations on gravity and magnetic geophysical data is identical to that which describes the behaviour of electrical filter circuits. It is more convenientto sho™ physical values which varies with time or space, frequency or wavenumber domain to carry out operation: on them. Convolution operation is to obtain filtered output data from input data by folding backward and multiplication with filter operators. The filter operators for every kind of filters, analytical continuations and derivatives can be obtained after determining frequency responses from Fourier transforms. The important phenomenonfor all operations is to determine frequency responses in frequency or wave - number domain. The measured potential field includes effects from all bodies in the vicinity. The effects from different sources can be separated withdata analysis up to a point. Interpretation would be improved if they could be separated and examined one by one.The regional gravity and aeromagnetic (flight height is 700 metres) maps were analysed with the above mentioned techniques for the region between 32°-33° E and 39° - 40° 30` N coordinates around Ankara - Polatlı area.The main structural trends were found to be NE - SW. In the south of the region, the deeper structures were foundto be trending NW - SE.