By Lisa Mol
School of Earth and Ocean Sciences, Cardiff University
Damage to immovable heritage frequently occurs during armed conflict and can have a significant detrimental impact on the future preservation of these sites. Widespread use of weapons in countries such as Iraq, Egypt, Syria and Libya, all of which contain large numbers of heritage sites, is a grave cause for concern and while the unrest continues it is difficult to obtain an accurate assessment of the damage incurred. This destruction of heritage is increasingly documented in the media, caught in the cross-fire or deliberately targeted to eradicate the cultural and religious identity of the opposition. Traces of damage are visible almost everywhere – the Tate Britain in London, the Main Building of Cardiff University, the General Post Office in Dublin all bear scars of conflict, to name but a few from the endless list. One of the major problems is that we simply do not know the short- or long-term implications of damage such as bullet and shrapnel impacts. We do not know how complex fracture networks created by these impacts respond to moisture movement, cementation initially weaken the stone or respond to environmental change over the decades and centuries following. Nor do we have a quick method of assessment which can be employed in the field in the direct aftermath of conflict. In fact, we have not got any idea how high speed impacts actually affect the integrity of the stone matrix, let alone how any ensuing damage might respond to environmental change.
The nature of warfare has drastically changed over the past century. The introduction of highly destructive weaponry such as grenades, bombs and machine artillery has increased the risk of damage or destruction of heritage in areas of conflict. Increasing velocity and effectiveness of the projectiles used in warfare have resulted in a far greater potential for damage. These high-impact weapons can leave historic materials’ surfaces weakened and vulnerable to accelerated deterioration processes.
While a significant body of engineering science research exists investigating the impacts of alien objects on surfaces, very little is known about the subsequent deterioration of the material (over decades to centuries). Bullet and shrapnel holes are mentioned only in passing in stone damage classification schemes, while fire and chemical damage from bombs and non-accidental pollution are investigated only by a few small scale studies.
In this section, we will explore the possibilities for science to contribute to our understanding of the long-term implications of this damage. For example, we can do field investigations, laboratory tests and simulations to figure out how damaged materials respond to the daily stresses of temperature changes, precipitation and how we can anticipate further damage.