Abstract:
Globally well-known ancient rock-hewn churches are present in Ethiopia in general and
particularly in the central and eastern parts of Tigray regional state. They are important sites of
heritage and tourism. Guahgot in the Adigrat region is the most solid monolithic rock hewn or
rock cut church not known to the outside world. Most of them are facing destabilization problem
in different degree due to natural and anthropogenic factors. Among the affected, two churches
hewn into sandstone located near the southern side of Guahgot, the Abreha-Atsibaha and Wukro
(Kirkos/Cherkos church) in Tigray region were chosen for detailed study in terms of geological
and engineering geological condition of the rocks in to which they are hewn. Both of them are
affected by weathering and seepage. Both are carved into Mesozoic Adigrat sandstone that
occupies higher elevations in topography, red in color and with iron and silica-rich alternating
bands. Petrographic data suggest that the rock is dominated by quartz followed by feldspars;
opaque and heavy minerals; pore spaces and carbonate/iron/silica cement. The rock
is characterized by low to medium unconfined compressive strength. The alternating bands with
varying mineralogical composition differ in mechanical properties and are responding differently
to weathering and erosion. This is resulting in the development of minor spalling, pitting etc in
the pillars, walls and roofs of the churches. Keeping the geological condition in view remedial
measures are to be planned to minimize deterioration with time.
