Stefano Cara, Carlo Matzuzzi: UAS proximal sensing for complex quarries 3D documentation UAS proximal remote sensing for complex ancient quarries 3D documentation Stefano Cara 1 , Carlo Matzuzzi 1 1 Institute of Environmental Geology and Geoengineering, National Research Council – Cagliari IT email: stefano.cara@cnr.it; carlo.matzuzzi@cnr.it Abstract The documentation of ancient quarries is often very critical due to the complexity of the archaeological sites. In this paper we discuss a method based on proximal sensing photogrammetry technique, to obtain detailed survey by means of an Unmanned Aerial Systems (UAS). This technique allows to acquire high definition digital images to generate, by means of semi-automatic photogrammetric algorithms, very dense point clouds and Digital Surface Model. The method based on UAS platforms allows to perform survey also in hazardous areas with reliability and safety, in order to obtain metrological data from 3D reconstruction of quarry sites. The proximal sensing survey was performed at different flight heights, according to the ground sample distance (GSD) needed to generate DSM by the combination of different photogrammetric shots at consistent resolutions. The flight planning is another very important step, that must consider steep or tall quarry walls and t5he variable exposition to the incident light, in order to minimize the errors on digital models and to obtain more detailed representation. This method allows to investigate on stone exploitation technology, volumes of the materials exploited and debris accumulation, geometrical and dimensional characteristics of the stone artefacts production. With approach we can also evaluate the archaeological heritage interactions with the environmental processes, as support of conservative and valorization projects. Keywords. UAS, Proximal Sensing, 3D modeling, Photogrammetry, Ancient Quarries 1 Introduction The aim of this work is to propose a methodological approach for proximal survey technique with UAS system for 3D detailed photogrammetric documentation of ancient quarries and stone artefacts, which could then be applied to other similar sites of interest. This technique allows to collect high definition digital images to generate very dense point clouds for DSM elaboration, particularly suited for quarry fronts, pillars and columns reconstruction. This study is focused on a Roman quarry area in Northern Sardinia, where pink/greyish granitic rocks have been used for column and pillars production. This area preserves some well known ancient stone quarries of the early second Century AD, when the trade of these materials interested the Imperial Rome and several Roman Provinces of the Mediterranean basin [1]-[10]-[13]. The dating of these quarries is supported by the archaeological investigation carried out on the vicinity of the Capo Testa area, particularly at the Santa Reparata bay, where a large quantity of pottery fragments and burials have been related to the mid-second Century AD [2].