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8. RESEARCH ON IRISH LANDSLIDESKoenraad Verbruggen8.1 IntroductionGiven the relative rareness of their occurrence it is not surprising that research on Irish landslides has beenlimited to date. However past events have often led to academic investigations and this was also the case forthe 2003 failures at Pollatomish and Derrybrien. Whilst the Irish Landslides Working Group (ILWG) cannot becertain that it is aware of all researchers that have looked at landslides in Ireland, particularly those who havemade brief visits from overseas, a comprehensive databank of published material, has been collated. Thischapter provides a brief overview of research on Irish landslides prior to 2003 and a summary of the projectscarried out as a result of the more recent events.8.2 Research pre-2003Earlier work carried out on Irish Landslides can be broadly divided into:-1. That conducted on specific failures and generally of a field and geomorphological nature, being descriptiveand carried out by geography/geology academics, some of which are reviewed below.2. The more geotechnical and laboratory based research into stability and behaviour of landslide materials,mainly glacial soils and peats, conducted by Civil Engineering Departments, some of which were referred toin Chapter 4 on the Geotechnics of Landslides in Ireland. A summary of current programmes is included.Early Irish landslide accounts have been used to populate the Irish Landslides Database event listings (Appendix5), but the majority are merely descriptive and the investigations do not really constitute research.Tomlinson (1979, 1981) of Queens University, Belfast, working on peat erosion and failures in Northern Irelandin the 1970’s and 1980’s, not only described events but also investigated their likely cause and possiblyimportant preconditioning factors. He believed an important factor in these failures, mostly of upland peat, wasthe presence of significant human disturbance such as the construction of townland boundary ditches, drainagechannels and peat cutting.Alexander, Coxon and Thorn, all then at Trinity College, Dublin (TCD), carried out research on peat failures inthe Geevagh area of County Sligo in the mid 1980’s (Alexander et al, 1986) and also documented failuresacross a wider area for a field guide of the Irish Quaternary Association (IQUA) (Alexander et al, 1985). TheGeevagh study area, which has been further worked on by O’Loinsigh at TCD proved the existence of previousfailures at the same location, in 1831 and 1945, all originating on the same upland ridge and being channelledinto the same catchment. Proof of this came from cores taken in the valley area, where each event could berecognised as a thin peat deposit within the soil profile and scars at different stages of regrowth, visible on thehillside. Approximations of flow velocity and strength were also made from the size of some of the boulders thatwere moved by the event.Fig. 8.1 Map of locality showing source of flow andstream sections, A Bog flow at Straduff Townland, CoSligo, (Alexander, et al., 1986).79