INTRODUCTION Geophysics is a subject of natural science is concerned with the physical processes and physical properties of the Earth and its surrounding space environment using the physics principles to the study of the earth's interior. It is therefore a threeof the principles of Physics to the Earth, Moon and Planets (Reynolds, Geophysics is applied to societal needs, such as mineral resources, mitigation of natural hazards and environmental protection. Geophysical survey data are used to analyze potential petroleum reservo deposits, locate groundwater and it also plays an essential role in the development of the theory of plate tectonics. The Earth acts like a large spherical magnet: it is surrounded by a magnetic field that changes with time and location. The field is generated by a dipole magnet (i.e., a straight magnet with a North and South Pole) located at the center of the Earth. The magnetic fields of geological bodies are superimposed on the background of the Earth's main field. Variations in magnitude and direction of this field influence both the magnitudes and shapes of local anomalies. The purpose of magnetic surveying is to identify and describe regions of the earth's crust that have unusual (anomalous)

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Ground magnetic survey was carried out using Scintrex proton precession magnetometer to map out subsurface structures and mineralization potentials at Alajawa area in Shanono, Kano State. 2D forward modelling was in the delineation of geological structures that are potential mineralization zones. Surfer 15 software was used to produce residual contour map. A total of five ( 5) profiles of the magnetic residual anomalies were modelled using Mag2dc software. The mineral potential locations were identified.

Aeromagnetic data over Lafia and environs have been analyzed to delineate the sedimentary thickness (Depth to Basement) and describe lineament features. Aeromagnetic data of the area comprising sheets 210 (Wamba), 211 (Kwolla), 231 (Lafia) and 232 (Akiri) covering an area of about 12,100 km 2 located between latitudes 8 o 00'N and 9 o 00'N and longitudes 8 o 30'E and 9 o 30'E were obtained from the Nigerian Geological Survey. Visual study of the Total magnetic intensity map, residual anomaly map and lineament maps show the presence of major lineament features trending NE-SW and NNE-SSW while the minor features trending E-W and NW-SE. Six profiles taken across the generated residual map were subjected to spectral depth analysis revealed two depth sources; the deeper magnetic sources range from 2.13 to 4.89 km, while the shallower magnetic sources range from 0.86 to 2.06 km. These shallower sources are probably due to the presence of igneous intrusives and/or magnetized bodies within the sedimentary cover. The temperature at depth ranges from 54.52˚C to 183.48 0 C with an average of 100.15 0 C. The South western and central parts of the study area were delineated as potential hydrocarbon target area due to the right temperature and sedimentary thickness.These areas correspond to Ajo, Obi, Keana, Abudem, Awena and areas between Ungwan Mai Samari and Kolen towns.

The total field aeromagnetic contour map located between geographic latitude 11 0 00'N to 11 0 30'N and longitude 7 0 30'E to 8 0 00'E was acquired, digitized and residualized in order to assess the Werner deconvolution method in the interpretation of geophysical data. Three profiles were selected for the interpretation of residual aeromagnetic anomalies. The result obtained from the data of Zaria area using Werner deconvolution method was filtered and shows that the depth to magnetic source values vary from 0.1 to 2.6km below the ground surface indicating the shallow nature of the magnetic source, while the susceptibility vary from 6.7x10-5 to 2.193 S.I unit approximately. The result obtained shows much correlation with some of the geophysical works carried out in the study area. The method is found to be simple, past and very effective.