3D monitoring of Paleolithic archaeological excavations using terrestrial laser scanner systems (Sierra de Atapuerca, Railway Trench sites, Burgos, N Spain)

Abstract

The advantages of active massive data capture devices such as LiDAR (Light Detection And Ranging) in the creation of high-resolution topographic models have been well known for years. They have been widely applied to the documentation of cultural heritage since the beginning of the 21st century. As LiDAR devices, terrestrial laser scanning (TLS) systems, or ground-based LiDAR, have shown themselves since then to have a multitude of applications and have proven clear advantages over classical survey methods. Nevertheless, few attempts have been made to use this method on Paleolithic archaeological excavations beyond one-time 3D reconstructions, which are mainly focused on forming a basis for conducting other studies. Since the excavation process involves the irreversible modification or destruction of deposits and spatial relationships that will not be reproduced again, the comprehensive reconstruction of excavation surfaces represents a fundamental issue for the research, dissemination, and conservation of Paleolithic sites. Through this work, we show the techniques and potential of the sequential geometric documentation of Paleolithic site excavations using TLS systems on the Sierra de Atapuerca Railway Trench sites (Gran Dolina, Galería and Sima del Elefante). Related to this sequential documentation, a case of application and a storage concept in Paleolithic archaeology is presented. As an application, the models were used to monitor the excavation surface changes and physical damage to excavation sections occurring during the last seven years. As a concept, multi-temporal models and derived information were stored in a database from which their design is displayed, the 4D (i.e., time dimension added to the three-dimensional spatial data) database. The results reveal TLS systems, 4D data, and 4D databases as efficient methods for providing detailed reconstructions, exhaustive change models, and storage of paleosurfaces, which could be applied also to other multi-annual excavation sites.