Ground Penetrating Radar Interpretation And Identification Of Light Petroleum Hydrocarbon Pollution In River Terraces

Light petroleum hydrocarbon pollution is one of the important sources of environmental organic pollution.GPR has achieved excellent results in detecting light petroleum hydrocarbon pollution in saturated zone,but poor results in detecting light petroleum hydrocarbon pollution in unsaturated zone.Inthis paper,the feasibility of detecting soil permittivity was verified by simulating ground penetrating radar?GPR?to detect clean soil moisture content through laboratory sandbox experiment,and then the feasibility of GPR to detect soil permittivity was simulated by laboratory experiment.The abnormal characteristics of radar profile in the polluted area were analyzed,and the effects of different soil media,water content and water conductivity on the detection effect of GPR were studied.The pollutant concentration and dielectric constant data in the polluted area were analyzed,and the pollution dielectric model was established,and the model was verified in the actual light petroleum hydrocarbon polluted site.The results showed that in the clean soil area,the permittivity and moisture content of the soil met the relation=-0.0013?_r³-0.0013?_r²+0.0394?_r-0.1103.In the soil area polluted by light petroleum hydrocarbon,the abnormal features of profile mainly include the abnormal features of parabolic shape with early reflection phase,increased energy and enhanced amplitude,or the abnormal characteristics of emission phase delay,energy attenuation and attenuation of radar signal.When the soil moisture conductivity is relatively high or the moisture content is relatively high,GPR is more effective in detecting light petroleum hydrocarbon pollution.When the soil moisture content is lower than 4.76%,GPR cannot accurately delineate the pollution range.Pollutant concentrations between the soil dielectric constant and dielectric model for:M₀={1.115?+[?1.341?-61.337?s_rw+2.882]n-4.8197}*?_d;Ground penetrating radar?GPR?can effectively detect the pollution range of light petroleum hydrocarbons in polluted sites.