Seismic refraction investigation of the subsurface structure at the southern part of Niger State College of Education, Minna, Nigeria

Abstract

This paper discussed the seismic refraction survey conducted at the southern part of Niger State College of Education Minna, in which a three-channel seismograph was used for the survey. The profiles were marked at 100m intervals, while the profiles lines traversed 1000m (1km). The exact site surveyed covers a total area of about 500,000m2. From the data collected, time – distance curves for each shot points were drawn, the velocities of the underlying layers for each points were obtained and the depths to the refractor layer were computed. The results obtained gave an overview of the lateral variation in the lithological changes of the subsurface earth materials in the surveyed area. The basement surface varied in depth, from depths as shallow as 2.05m to a maximum of 10.13m. The rock materials identified in the surveyed area are chiefly sand, saturated clay, gravel, and granite.

Keyword: Basement, aquifer, Seismograph, time-distance curve, and velocity.