3D-Radar 1 article published in JoVE Environment Tracking Infiltration Front Depth Using Time-lapse Multi-offset Gathers Collected with Array Antenna Ground Penetrating Radar Hirotaka Saito1, Seiichiro Kuroda2, Toshiki Iwasaki1, Haruyuki Fujimaki3, Nobuhito Nagai4, Jacopo Sala5 1Graduate School of Agriculture, Tokyo University of Agriculture and Technology, 2National Institute for Rural Engineering, National Agriculture and Food Research Organization, 3Arid Land Research Center, Tottori University, 4GeoFive Co. Ltd, 53D-Radar Here we present a Ground Penetrating Radar (GPR) system based on a ground-coupled, densely populated antenna array for monitoring the dynamic process of subsurface water infiltration. A time-lapse radar image of the infiltration process allowed estimating the depth of the wetting front during the course of the infiltration process.