ASSESSMENT OF THE GEOHERITAGE VALUE OF VOLCANOES AND FAULTS – (HOW) CAN THEY BE QUANTIFIED?

The development of semi-quantitative methods for geoheritage assessment has allowed comparison and more rigorous comparison of sites. Now the opportunity opens up for applying such methods more widely. Different geological sites probably require specifically adapted methods for geosite quantification. Volcanoes and faults have particular geological and geomorphological expressions and so require their own specific geosite classification and quantification procedures. Our recent experience with promoting a tectonic rift and monogenetic volcanoes has lead us to develop a classification scheme for both, that can be adapted for geosite assessment. Starting from the general, and the large-scale tectonic environment, the branching classification in each case is like a Bayesian tree, acknowledging uncertainty in the decision process, and allowing for modification as more information comes available. We provide the examples of monogenetic volcanoes and rift faults that illustrate how the classification descends from 'monogenetic volcano', through different geological environments to individual volcano geotypes and their features. The classification can become very complicated, and to not become meaningless simplification and subjective strategic decisions have to be taken to keep the results useful. We think this process is a useful exercise to improve the comparative analysis between sites, and can help avoid some of the pitfalls of subjective qualitative approaches.