Salt Damage on the Wall Paintings of the Festival Temple of Thutmosis III, Karnak Temples Complex, Upper Egypt. A Case Study

Abstract

The present study aims to characterize the main deterioration mechanisms affecting the wall painting of the festival temple of Thutmosis III, in the Karnak temples complex, Upper Egypt. Several salt encrustations were observed on the painted surfaces, exhibiting different degrees and forms of decay. The morphology and the microanalysis of the contained mineral phases were studied using scanning electron microscopy together with an energy dispersive X-ray analysis system (SEM-EDS). The mineralogical characterization was performed using the X-ray powder diffraction method (XRPD). The climatic conditions of the area play an important role in the crystallization/recrystallization cycles of salts, which exerts additional pressure, by producing cracking, powdering and flaking, in addition to pulverization of the pictorial layers. The results showed that sodium chloride (halite, NaCl) is the predominant salt species affecting in the site. Furthermore, other salt minerals, such as sylvite (KCl), niter (KNO3), natron (Na2CO3·10H2O), thenardite (Na2SO4), gypsum (CaSO4·2H2O), anhydrite (CaSO4) and bassanite (CaSO4·0.5H2O) were also found. The obtained results allowed us to determine the main deterioration factors and may be used when applying a conservation plan