Geotechnical and geophysical characterization of Moai statues—Rapa Nui Easter Island (Chile)

摘要

Major cultural heritage of Easter Island are the MOAI statues, carved on local tuff from Ranu Raraku quarry. Most statues are presently affected by extensive weathering caused by marine spray and climate factors that produce alteration of tuff primary minerals. A geomechanical and geophysical survey and sampling of rock materials forming the statues has been developed. Geodetic surveying activity was implemented aimed at 3D reconstruction of the Moai statues geometry. Data indicated that the Moai are mainly formed by palagonite tuff rock and though low seismic velocities were not detected (due to their saturation degree) the material can be classified as soft rock. The main target of the interdisciplinary study, has been a research program finalized to the comprehension of rock strength and deformation parameters as well as the weathering mechanisms and processes in order to provide to local authorities a scientific and technical support for the conservation of Rapa Nui heritage and identity.