Diagnóstico de factores ambientales que inciden en el deterioro de estelas prehispánicas del sitio arqueológico de Oxpemul Campeche, (reserva de la biosfera de Calakmul)

Abstract

Oxpemul is an archaeological site located in the Calakmul Biosphere Reserve (Campeche, Mexico). This site has important pre-Hispanic vestiges formed from limestone and considered cultural heritage. The stelae located at this site have important epigraphic registers about the history of the site and Mayan culture; therefore, these Mayan buildings are considered the most representative vestiges of this site, due to the information found on their surface. However, environmental and climatic conditions have caused that these structures suffer a severe natural weathering process; consequently, this information can be lost. In this work, the impact of environmental and climatic factors on the weathering of four stelae located at Oxpemul was studied using different characterization techniques, such as Digital Photography (DP), luminescence by UV-Visible Photography, Ion Chromatography (IC), Scanning Electron Microscopy/Energy Dispersive Spectroscopy (SEM/EDX), X-Ray Fluorescence (XRF), Infrared Spectroscopy (IR), and X-Ray Diffraction (DRX). The results show that water availability, environmental CO2, and the ion solubility of mineral components are the key factors involved both in the dissolution process of carbonates and hydrolysis of silicates in the stone of the stelaes. In addition, these factors have demonstrated favor the bioreceptivity of the stone causing biodeterioration processes and allowing the formation of neoformation products that cause the weathering and loss of material with historical information.This is the first study carried out to identify and understand the weathering processes that occur in these stelae; therefore, this information could be useful to establish strategies for preserving, conserving, and/or restoring these vestiges.