After the Irpinia earthquake in 1980 caused further weakening of Pompeii ’s crumbling walls , systematic initiatives were put into place to evaluate the damage . The excavation team took documentary photographs , conducted a systematic survey , and recorded the qualitative data through a computer processing system . From these findings , Mariette de Vos calculated that the number of existing paintings made up only ten percent of what was originally found in earlier excavations , while another ten percent was only known through drawings and photos . For the first time , the team was able to show that Pompeii had indeed been over-excavated , and provide a comprehensive view of how , where , and to what extent conservation and restoration was needed
Irpinia earthquake in 1980
1980 Irpinia earthquake
Conservation and restoration of Pompeian frescoes