Stone monuments of the Nemrud Dag sanctuary/Turkey - petrographical investigation and diagnosis of weathering damage

The sanctuary of the Nemrud Dag in Eastern Turkey represents outstanding world cultural heritage. It was built by King Antiochos I of Commagene in the first century B.C. It is composed of a tumulus and three terraces. The west and east terrace are famous for their colossal limestone statues and sandstone stelae. These stone monuments have suffered weathering damage. The awareness of increasing damage and the danger of further irretrievable loss of cultural heritage have resulted in international efforts for sustainable monument preservation. Studies have been carried out, targeted to damage diagnosis as a fundamental contribution to appropriate monument preservation. The investigation has so far focused on the sandstone monuments and combines laboratory analysis of representative stone samples and in-situ investigation of the weathering damage by means of monument mapping and ultrasonic measurements. Field work was conducted in 1988 and 2002. Results are presented for the sandstone monuments regarding petrographical properties, state of weathering, rating of weathering damage and weathering progression. In addition, preliminary results are presented for the limestone monuments. The findings reveal a considerable petrographical range of the sandstones. The extent of damage on the sandstone monuments and weathering prognoses derived from evaluation of weathering damage indicate the need and urgency of monument preservation measures.