Magnetic susceptibility measurement was carried out on 26 top-soil samples randomly collected from the study area and 5 selected top-soil samples outside the station, using the Bartington MS meter linked to a computer operated using Multisus2 software. The Measurements was done at both low (0.47 kHz) and high (4.7 kHz) frequency susceptibilities which was further used to calculate the frequency dependent susceptibility (Χ FD ). The values for low frequency mass magnetic susceptibility ranges between 96.6×10 −5 m 3 kg −1 and 146×10 −5 m 3 kg −1 with an average value of 117.35×10 −5 m 3 kg −1 and standard deviation of 12.22×10 −5 m 3 kg −1 . The result reveal high magnetic susceptibility values at the station compared with the values observed outside the station which ranges between 53.0×10 −5 m 3 kg −1 and 72.3×10 −5 m 3 kg −1 with an average value of 63.2×10 −5 m 3 kg −1 and standard deviation of 7.01×10 −5 m 3 kg −1 . This significant magnetic enhancement indicates high concentration of ferrimagnetic minerals in the soil and thus evidence of pollution due to the activities at the station which implies that the magnetic enhancement is of anthropogenic source than pedogenic and lithogenic. Analysis of the heavy metals also reveals higher values at the station. The correlation analysis between the mass specific magnetic susceptibility and the heavy metals concentrations (i.e. Cu (R=0.92), Fe (R=0.88), Cr (R=0.85), Zn (R=0.83), Cd (R=0.79), Mg (R=0.72), Mn (R=0.60), Pb (R=0.67)) which was conducted to further investigate the relationship between the soil magnetic susceptibility values and elemental variations, demonstrated magnetic susceptibility can be used as a proxy method for assessing the pollution of these heavy metals.There is no funding received for this research work. ORCID iDsMuyiwa Michael Orosun https://orcid.org/0000-0002-0236-3345 Naheem Banji Salawu https:/ /orcid.org/0000-0001-5089-2359 Louis Hitler https://orcid.org/0000-0002-0286-2865 ReferencesAyoubi S and Adman V 2019 Iron mineralogy and magnetic susceptibility of soils developed on various rocks in western Iran Clay and Clay Minerals. 67 217-27 Ayoubi S and Karami M 2019 Pedotransfer functions for predicting heavy metals in natural soils using magnetic measures and soil properties J. Geochem. Explor. 197 212-9 Beget J E, Stone D B and Hawkins D B 1990 Paleoclimatic forcing of magnetic susceptibility variation in alaskan loess during the late quaternary Geology 18 40-3 Blundell A, Dearing J A, Boyle J F and Hannam J A 2009 Controlling factors for the spatial variability of soil magnetic susceptibility across England and Wales Earth Sci. Rev. 95 158-88 Brempong F, Mariam Q and Preko K 2016 The use of magnetic susceptibility measurements to determine pollution of agricultural soils in road proximity Afr. J. Environ. Sci. Technol. 10 263-71 Caggiano R, Coppola R, Di Leo S, Macchiato M and Ragosta M 2005 Comparison between in situ soil magnetic susceptibility measurements and heavy metal concentrations: the case of the...

Se realizó una investigación sobre el efecto que tienen algunas actividades humanas en la susceptibilidad magnética y la susceptibilidad dependiente de la frecuencia: el estudio se realizó en Jalingo, estado de Taraba, Nigeria, en la superficie del suelo de una zona comercial, un estacionamiento de autos y una zona escolar. El objetivo fue evaluar la variación de la susceptibilidad magnética con distintos tipos de uso de la tierra y detectar los puntos más contaminados utilizando los parámetros de proxy magnéticos. Con ello se evaluó la contribución de superparamagnéticas (SP), del tamaño de un grano, a

In this study, determination of magnetic susceptibility were carried out on 366 soil samples using MS2B magnetic susceptibility meter connected to a computer system using MULTISUS2 software. The soil samples were selected from six sites namely: Shell environment, Nigeria Liquefied Natural Gas environment, Port Harcourt Refining Company James Hart, New Jerusalem and Port Harcourt respectively. Three of the six sites; Shell, NLNG and Port-Harcourt Refining Company environments have their soils contaminated with hydrocarbon. One hundred and ninety two (192) soil samples were collected from these hydrocarbon contaminated sites and 174 from non-hydrocarbon contaminated soil (control samples). The magnetic susceptibility values obtained from Shell environment and for hydrocarbon samples showed higher (enhanced) magnetic susceptibility with average values of 117.54x10-8 m3kg-1 and 2016.39x10-8 m3kg-1 and a moderate magnetic susceptibility for with an average value of 20.83x10-8 m3kg-1 in comparison to magnetic susceptibility values obtained from the control samples whose average values were 2.39x10-8 m3kg-1, 12.42x10-8 m3kg-1 and 3.31x10-8 m3kg-1 for James Hart, New Jerusalem and Port Harcourt respectively. This means that the hydrocarbon sites are highly magnetic which could be indication of pollution. The results of the percentage frequency dependent susceptibility (χFD%) obtained in the hydrocarbon samples showed about 16% of the samples had percentage frequency dependent susceptibility (χFD%) values between 0-2%, 53% had values of χFD% between 2-10% and 31% had χFD% between 10-12% and above while about 21% of the control samples had χFD% values between 0-2%, 58% between 2-10% and 21% between 10-12% and above. The high magnetic susceptibility value in the hydrocarbon soil samples is an indication of pollution due to hydrocarbon deposit. The Government is therefore advised to monitor the location and activities of the oil companies and initiate quick mop up strategies should be put in place in the eventuality of oil spillage.