Preliminary digital health record of limestone walls in Al-Ziggurat, Al-Nimrud city, Iraq

This study deals with the preliminary establishment of the so-called digital health record of an ancient monument: the Al-Ziggurat in Al-Namrud city, Iraq. This documentation tool is designed to store, organize and analyze heterogeneous data about the states of a monument around a 3D model. To promote and spread the use of this new digital technique, a low-cost and highly portable application is proposed here. The present study compares the mapping of degradation, and the mapping of the previous state of burial, stored and displayed on the 3D photomodel of Al-Ziggurat walls, in order to provide a preliminary analysis and diagnosis of the origin of stone degradations. Photogrammetric techniques appear suitable to create a primitive-based 3D model with textured surfaces for the drawing and the representation of mappings. It is concluded that gypsum pollution from the soil may trigger or enhance new degradations on the recently excavated walls through direct contact with stone or transport of dust by the wind.