Study of the Chemical and Biological Weathering Effects on Building Stones of the Ancient City of Sabratha, NW-Libya

By: Ismail Shushan , Saddik Kamyra , Hitham Minas

University of Elmergib, Al-Khums

Issue: Vol 24 |First Issue |2025

article language: English

Abstract:

This paper examines the chemical and biological weathering factors and their effects on different types of building stones in the ancient city of Sabratha. The study is based on Group 2 of weathering proposed by Fitzner and Heinrichs (1999, 2000, 2004), known as "Discoloration/Deposit." Field observations identified six main weathering forms affecting the building stones of Sabratha Archaeological City: soiling effect, biological colonization, biological colonization with crust, discoloration, loose salt deposits, and hard crust deposits. These included nine specific weathering types such as soiling from anthropogenic impact, soiling by droppings, higher plant colonization, microbiological colonization, colonization forming dark crusts, bleaching, coloration, efflorescence, and formation of light-colored crusts. The degree of damage ranged from non-visible to moderate, with the extent of spread varying from very limited to widespread. The linear and progradational indices of this weathering group also showed damage levels from non-visible to moderate. The findings indicate that both chemical and biological weathering contribute to the ongoing deterioration of the ancient stone structures in Sabratha, highlighting the need for conservation measures to protect the city’s heritage.

Keywords: chemical weathering, biological weathering, ancient building stones, ancient city of Sabratha.