التجوية و آثارها الجيوموفولوجية في تشكيل مقابر الأنفوشي الأثرية بمدينة الإسكندرية-مصر : دراسة حالة الجيومورفولوجيا التطبيقية

Abstract EN

El-Anfoshi Tombs are Greco-Roman archaeological remains that had been excavated through the Pleistocene coastal ridges of Oolitic limestone.

They are composed of five tombs lie in front of Ras El-Tin Palace at latitude 31o 12› 08›› N and longitude 29o 52› 27›› E as defined in the current study using the GPS.

Several previous literatures had been published on weathering of archaeological sites world-wide i.e.

at a wide range of environmental conditions from the extreme cold humid regions to hot dry regions.

Several protocols of study had been planned and followed to achieve their aims around this topic.

The current study is considered as a pioneer in the plan of investigation and the advanced techniques used to achieve the aims of study that is restricted in two points, namely; investigation of weathering processes and mechanism prevailing on El-Anfoshi Tombs, and defining the damage categories on micro-scale and macro-scale at each part of these tombs using the latest published field classifications and the Damage Category including All Weathering forms Scheme «DCAW» as well as laboratory tools as transmitting polarizing microscope, Scanning Electron Microscope «SEM», magneto-structive ultrasonic waves, X-ray diffraction «XRD», and the hydrochemical analysis for stagnant water flooding the basal parts of these tombs as well as tiny weathered rock samples at these tombs.

The results indicated that the bedrock through which these tombs had been excavated is oolitic limestone with oolite grains cemented by microspar and sparite, the rock›s porosity is considerably high due to rock›s texture deformation by weathering particularly salt weathering that can be detected on mega-scale by salt efflorescence, honeycomb and tafoni, scaling, exfoliation, fracturing, demolishing of inscriptions at stone surface.

Not only that but lso on micro-scale detected by SEM and numerically by ultrasonic waves› parameters mainly the velocity of ultrasonic waves «Cp» and rock›s internal friction «Qc».

It is indicated salt crystallization within rock›s pores and the velocity of the ultrasonic waves has been raised due to creation of secondary porosity by stresses created on rock›s texture by salt growth within rock›s pores.

The overall damage category of these tombs, using the dimensions of all weathering forms at this site, with the aid of DCAW indicated that these tombs have very severe damage category on macro-scale where the most impressive archaeological features (mainly inscriptions and paints) had been totally removed on rock›s weathering.

The total dissolved salts confirmed the role of salt weathering as a leader weathering process acting on this site by salt crystallization and/or salt hydration for the chlorides and sulfates respectively at such humid semi-arid region.

The biological weathering comes in the second order of weathering acting at this site particularly at the semisheltered parts flooded by stagnant water derived to this low topography area from the surrounding multi-storey recent buildings with old pipes percolating domestic water enriched with variable salt types reaching the lower parts of these tombs via inter-connected rock pores.

The recommendations regarding this detailed study at such highly valuable site representing part of the Egyptian history are; quick restoration of the different parts of these tombs through salt with-draw using clay or paper politic saturated with bi-distilled water at summer time; stopping of water percolation from bad water pipes of recent buildings adjusting this site; detailed study for type of biological cover at this site to find out the most suitable technique for its removal without any side effect on the main rock mass of these tombs.