In-Phase/Quadrature Signatures of a Very LowFrequency Electromagnetic Survey for the Delineation of Cassiterite at Rafin Bareda, DutsenWai, Kaduna State, Nigeria

Abstract

The VLF-EM geophysical technique was used to delineate the zones of cassiterite at Rafin Bareda, Dutsen-Wai, Kubau Local Government area of Kaduna State, Nigeria which is located at Latitudes 10°51'46''N and Longitudes18°12'50''E. The research covered eleven profiles taken uniformly in the West-East direction each of length 1000 m with a total of 1100 stations. Scentrix VLF equipment was used to obtain the VLF-EM data (In-phase and Quadrature in percentages) with a detected field of 19.1 kHz transmitter in Rosnay, France. The plots of in-phase and Quadrature revealed various cross-overs (fractures/mineralized zones). However, the Fraser filter of the in-phase components was employed to reduce noise and enhance signal strength. Consequently, the Fraser-filtered of in-phase plots peaks around the crossover which confirmed the probable fractured/mineralized cassiterite zones. The Fraser filtered of the in-phase components revealed the continuous and extending nature of probable mineralized cassiterite zones which are dominant on profiles G and H.

Keywords

• cassiterite
• rafin bareda
• vlf-em method
• in-phase
• quadrature
• fraser-filtered