Visualisation of 3D GPR Surveys: Application of virtual reality in geosciences

Ground Penetrating Radar (GPR) is increasingly applied to image 3D structures in the shallow subsurface. To exploit the 3D character of the data, we have experimented with a combination of virtual reality (VR) techniques and "pseudo volume-visualisation". A simple prototype of interactive visualisation software has been implemented for different VR display systems (Workbench, Cave). In one of the visualisation modes only strong positive and negative signal amplitudes of the radargrams are rendered. This reduces the amount of data and allows the course of a prominent reflector to become visible in the 3D space. A real world data set was interpreted with standard methods and subsequently visualised with the prototype software. VR technique allows to render the data in 3D space without prior interpretation which is necessarily subjective. It is also suitable for visual integration of data from different geophysical methods, like e.g., borehole and electric measurements, an d for discussion of a data set with several investigators.