USE OF GEOGRAPHICAL INFORMATION SYSTEM APPROACHES FOR THE DIAGNOSIS OF SAN ISIDORO RUINS (MADRID, SPAIN)

Abstract. This article shows the application of different geoinformatic approaches for the diagnosis of a small hermitage located at the Spanish capital of Madrid. More specifically Structure from Motion photogrammetry for the 3D digitalization and orthophoto generation, and Geographical Information System (GIS) for uploading and management of the information were used. Both strategies were carried out using open-source software. In the case of the GIS approach the QGIS platform was chosen and some additional features were programmed to facilitate the diagnosis such as the creation of standardized HTML files to improve the interoperability. The pre-diagnosis phase was carried out by means of the Qfield android application that allows capturing the data on field. Additionally, several previous test, i.e. X-ray diffraction, microscopy and physical tests were carried out with the aim of understanding the severe degradation process that this Hermitage is suffering. This multidisciplinary approach allows us to understand the current status and degradation mechanisms of the Hermitage on which the most prominent damages are the features induced by material loss. This damage is related with the environmental conditions of the sites as well as the physical and chemical properties of the stone used during its construction.