Shallow depth extent of the Lesutoskraal granophyre dike in the Vredefort impact structure: Geophysical surveys and trenching data

Abstract Recent observations and geophysical studies at the Vredefort impact structure have indicated that melt dikes in central uplift of small depth extents. In this study, we performed magnetic electrical resistivity tomography (ERT) surveys Lesutoskraal granophyre dike (LGD) trenched to confirm its extent. The ERT survey showed outcrops LGD are associated with shallow resistive zones <3 m extent, but such do not occur where absent. Visual trench confirmed has a extent (~0.75 m) location. However, revealed anomalies along entire strike dike, even no occur. We suggest remagnetization host rock within metamorphic contact aureole could explain presence absence outcrops. Considering results survey, made trench, surface distribution LGD, (<3 length propose represent intersection terminus current erosional surface.