Modelling of underground objects and geological-tectonic structures from a point cloud: application of the developed models in studies of geodynamic processes

Wrocław University of Science and Technology, Faculty of Geoengineering, Mining and Geology, 27 Wyb. Wyspiańskiego St., 50-370 Wrocław, Poland

^* Corresponding author: damian.kasza@pwr.edu.pl

Abstract

At present, techniques of terrestrial laser scanning are one of the most popular survey methods. They allow for fast and non-invasive data acquisition even up to several tens of thousands points per minute. Apart from high precision and measurement efficiency, one of its assets is the possibility of working in objects with natural or artificial light. Due to this, the method may be successfully used in activities related e.g. with the surveying of the present state of underground excavations. The basic product derived from laser scanning measurements is a point cloud. This set is the input data for the construction of a 3D object with a closed surface, e.g. a mesh network. This paper presents the results of inventory works performed in a complex of underground excavations below Książ Castle in Lower Silesia (SW Poland). Based on a point cloud acquired during the measurements, a 3D model of the excavations was constructed. Open source software – MeshLab – was used in the modelling. The high-resolution, calibrated metric model of the underground excavations allowed for a macroscopic recognition of the position of the main tectonic structures cutting the space of the underground excavations. The obtained model was supplemented with the results of earlier geodetic and geological surveys, performed in 2013-2015. The generated model of the geological structure in the study area is an element supporting the interpretation of kinematic activity of the rock massif registered by the instruments of the SRC PAS Geodynamic Laboratory in Książ.