GSTOP: a new tool for in field recording of 3D geological data

The STOP is a new product that integrates an orthophoto (2D photographic map) with the height values derived from the Dense Digital Surface Model (DDSM) generating georeferenced 3D information. In fact, STOP can be view using an experimental software tool, developed by the authors in Visual Fortran that includes simple query functions, a 3D coordinate viewer, some measurement commands (e.g., angles, 3D distances, areas, planes, volumes), georeferenced note and comment record utilities. This viewer can be used on a simple netbook or tablet PC permitting the surveyor to acquire, directly on the field, the 3D geological information in a rapid, comprehensive and accurate way. In fact, the GSTOP (GNSS STOP) viewer can manage, in real time, a direct connection with navigation sensors as a low cost GPS/GNSS receiver to define the current location and a low cost IMU sensor to measure attitude angles (heading, pitch and roll ) of PC: inside the STOP, the user can view his position (a red circle) and the azimuth of line of vision (a red arrow) and generate a 3D solid image in order to be compared the effective scene. The application was used to produce a detailed geologic map and the reconstruction of Quaternary evolution of the area. The STOP viewer was tested by producing a digital map of the Quaternary sediments and landforms in a 3-km2 area of the Rodoretto Basin, a minor tributary of the Germanasca Valley, shaped in the greenstone and schist of the Piemontese zone (Northwestern Italy).