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| [They generally] proposed landslide risk1 zonations or a terrain index showing the stability of hillsides. The term “risk” used here could be considered similar to landslide susceptibility. According to Varnes (1984), as the term “terrain index” is also intended to show a quantitative rating of stability, it is closer to the concept of susceptibility than hazard or risk.
Landslide susceptibility was quantitatively first approached by Brabb et al. (1972). They introduced a semi-quantitative method consisting of a bivariate analysis of landslide area percentages in slope angle intervals, expressed by relative susceptibility numbers, from which a susceptibility zonation was obtained. This pioneering paper offered a formal definition of landslide susceptibility as an indication of how prone to landsliding a land unit may be. It also offered a method to classify terrain units with a relative susceptibility number based on geological units, slope angle and percentage of landslides in the unit, which was a very difficult task to apply at that time. Another approach to mapping landslides involves landslide density or isopleth maps. Campbell (1973) presented a nominally objective method for a statistical assessment of regional landslide distribution based on Schmidt and Mac Cannel (1955). The technique was based on a landslide inventory at a 1:24,000 scale (Campbell, 1973) by estimating the surface covered by landslide deposits using a number of contiguous circles displayed on a grid, calculating the percentage of the surface area covered by each circle and contouring equal percentage intervals. With the computer revolution, Lessing et al. (1976) in West Virginia (USA), Newman et al. (1978) in the San Francisco Bay region and Carrara et al. (1977, 1978) in the Ferro basin (Calabria, Italy), introduced computer techniques to analyze landsliding factors in order to obtain what they called slide-prone areas, landslide susceptibility or landslide hazard zonations, all of which lacked any temporal forecasting. The widespread availability of computing power allowed statistically supported landsliding zonations to be obtained, e.g. landslide susceptibility using discriminate factors (Simons et al., 1978) and landslide hazard using bivariate (Neulands, 1976) or multivariate analysis (Carrara, 1983). One of the really significant contributions to landslide research comes from the pioneering work of Carrara and Merenda (1976), Carrara (1983) and Carrara et al. (1977, 1978). Varnes (1984) described the contributions of Carrara et al. (1978), on the landslides in the basin of the Calabria–Lucania border, Italy, as ‘‘one of the more advanced and accessible state-of-the-art analyses of land attributes for production of landslide hazard maps, utilizing computer processing’’. The objectives were to statistically define slope instability by multivariate analysis and, using a computer, to create a slope instability hazard map. 1 Risk is defined as the probability of meeting danger or suffering harm or loss. In relation to disaster, risk has been more specifically described as the probability that a disaster will occur, using relative terms such as high risk, average or medium risk and low risk to indicate the degree of probability. Brabb, E.E., Pampeyan, E.H., Bonilla, M.G. (1972): Landslide susceptibility in San Mateo County, California. US Geological Survey Miscellaneous Field Studies, Map MF-360, scale 1:62,500. Campbell, R.H. (1973): Isopleth map of landslide deposits. Point Duma Quadrangle, Los Angeles County, California: an experiment in generalizing and quantifying aerial distribution of landslides. US Geological Survey Misc. Field Investigation Map MF-535. USGS, California. Carrara, A., Merenda, L. (1976): Landslides inventory in northern Calabria, southern Italy. Geol. Soc. Am. Bull 87:1229–1246. Carrara, A., Pugliese, E., Merenda, L. (1977): Computer based data bank and statistical analysis of slope instability phenomena. Z Geomorph NF 21(2):187–222. Carrara, A., Catalano, E., Sorriso-Valvo, M., Really, C., Osso, I. (1978): Digital terrain analysis for land evaluation. Geologia Applicata e Idrogeologia 13:69–127. Carrara, A. (1983): Multivariate methods for landslide hazard evaluation. Math Geol 15:403–426. Lessing, P., Kulander, B.R., Wilson, B.D., Dean, S.L., Woodring, S.M. (1976): West Virginia landslides and slide-prone areas. West Virginia Geol. Econ. Surv., Environ. Geol. Bull., 15:64. Neulands, H., (1976): A prediction model of Landslip. Catena 5:215–30 engineering geology maps: landslides and GIS 405. Newman, E. B., Paradis, A. R., Brabb, E. E. (1978): Feasibility and cost of using a computer to prepare landslide susceptibility maps of the San Francisco Bay region, California. US Geological Survey Bulletin 1443, USGS, USA, pp 23. Schmid, R. H., MacCannel, J. (1955): Basic problems, techniques and theory of isopleth mapping. J. Am. Stat. Assoc., 50(269):220–239. Simons, D. B., Li, R. M., Ward, T. J. (1978): Mapping of potential landslide areas in terms of slope stability. Fort Collins, Colorado. Civil Engineering Dept., Colorado State University, pp 75. Varnes, D. J. (1984): Landslide hazard zonation: a review of principles and practice, International Association of Engineering Geology, Commission on Landslides and Other Mass Movements on Slopes, UNESCO Natural Hazards Series no. 3, pp 61. |
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Landslide susceptibility is a measure of how prone land units are to landsliding, and was quantitatively approached by Brabb et al. (1972). [Page 347] They generally propose landslide risk zonations (Stevenson 1977; Méneroud 1978; Méneroud and Olivier 1978) or a terrain index showing the stability of hillsides (Vecchia 1978). The first two approaches used the term ‘‘risk’’ in a sense that could be considered similar to landslide susceptibility, although the method of Stevenson (1977) included a land use [Page 348] factor rated from 1 for woodland to 1.25 for land cleared or built-on with special precautions, and 1.5 (maximum) for land built-on without special precautions. Varnes (1984) refers to Vecchia’s (1978) use of criteria which reflect geomechanical rock mass classifications. As the terrain index is also intended to show a quantitative rating of stability, it is closer to the concept of susceptibility than hazard or risk. Finally, Brabb et al. (1972) introduced a semi-quantitative method consisting of a bivariate analysis of landslide area percentages in slope angle intervals, expressed by relative susceptibility numbers, from which a susceptibility zonation was obtained. [...] This pioneering paper offered a formal definition of landslide susceptibility as an indication of how prone to landsliding a land unit may be. It also offered a method to classify terrain units with a relative susceptibility number based on geological unit, slope angle and percentage of landslide in the unit, which was difficult to apply at that time. [...] Another approach to mapping landslides involves landslide density or isopleth maps. Campbell (1973) presented a nominally objective method for a statistical assessment of regional landslide distribution based on Schmidt and Mac Cannel (1955), which was used and discussed in later works (Wright and Nilsen 1974; Wright et al. 1974; Pomeroy 1978; DeGraff and Canutti 1988; Collins 1987; DeGraff 1985; DeGraff 1987) and brought up to date for microcomputers and GIS for landslide spatial incidence by Bulut et al. (2000) and Valadaö et al. (2002) and for the assessment of landslide spatial–temporal incidence by Coe et al. (2000). The technique was based on a landslide inventory at a 1:24,000 scale (Campbell 1973) by estimating the surface covered by landslide deposits using a number of contiguous circles displayed on a grid, calculating the percentage of the surface area covered by each circle and contouring equal percentage intervals. [...] With the computer revolution, Lessing et al. (1976) in West Virginia (USA), Newman et al. (1978) in the San Francisco Bay region and Carrara et al. (1977, 1978) in the Ferro basin (Calabria, Italy), introduced computer techniques to analyse landsliding factors in order to obtain what they called slide-prone areas, landslide susceptibility or landslide hazard zonations, all of which lacked any temporal forecasting. The widespread [Page 349] availability of computing power allowed statistically supported landsliding zonations to be obtained, e.g. landslide susceptibility using discriminate factors (Simons et al. 1978) and landslide hazard using bivariate (Neulands 1976) or multivariate analysis (Carrara 1983). [...] [...] One of the really significant contributions to landslide research comes from the pioneering work of Carrara and Merenda (1976), Carrara (1983) and Carrara et al. (1977, 1978). Varnes (1984) described the contributions of Carrara et al. (1978), on the landslides in the basin of the Calabria–Lucania border, as ‘‘one of the more advanced and accessible state-of-the-art analyses of land attributes for production of landslide hazard maps, utilising computer processing’’. [...] The objectives were to statistically define slope instability by multivariate analysis and, using a computer, to create a slope instability hazard map and maps to relate the presence of man-made structures and landslide hazard. [...]
Brabb EE, Pampeyan EH (1972) Preliminary map of landslide deposits in San Mateo County, California. US Geological Survey Miscellaneous Field Studies, Map MF-344, scale 1:62,500 Campbell RH (1973) Isopleth map of landslide deposits. Point Duma Quadrangle, Los Angeles County, California: an experiment in generalizing and quantifying areal distribution of landslides. US Geological Survey Misc. Field Investigation Map MF-535. USGS, California Carrara A (1983) Multivariate methods for landslide hazard evaluation. Math Geol 15:403–426 Carrara A, Merenda L (1976) Landslides inventory in northern Calabria, southern Italy. Geol Soc Am Bull 87:1229–1246 Carrara A, Pugliese E, Merenda L (1977) Computer-based data bank and statistical analysis of slope instability phenomena. Z Geomorph NF 21(2):187–222 Carrara A, Catalano E, Sorriso-Valvo M, Really C, Osso I (1978) Digital terrain analysis for land evaluation. Geologia Applicata e Idrogeologia 13:69–127 Lessing P, Kulander BR, Wilson BD, Dean SL, Woodring SM (1976) West Virginia landslides and slide-prone areas. West Virginia Geol Econ Surv, Environ Geol Bull 15:64 Méneroud JP (1978) Cartographie des risques dans les Alps- Maritimes (France). In: Proceedings of the IIIrd I.A.E.G. Congress, II, Chap. 46, pp 98–107 Méneroud JP, Olivier G (1978) Eboulement et chutes de pierres sur les routes. Methode de cartographie. Groupe d’Etudes des Falaises (GEF). Rapport de recherche LPC no. 80, L.C.P.Ch., Paris, France, 63 pp Neulands H (1976) A prediction model of Landslip. Catena 5:215–30 Newman EB, Paradis AR, Brabb EE (1978) Feasibility and cost of using a computer to prepare landslide susceptibility maps of the San Francisco Bay region, California. US Geological Survey Bulletin 1443, USGS, USA, 23 pp Schmid RH, MacCannel J (1955) Basic problems, techniques and theory of isopleth mapping. J Am Stat Assoc 50(269):220–239 Simons DB, Li RM, Ward TJ (1978) Mapping of potential landslide areas in terms of slope stability. Fort Collins, Colorado. Civil Engineering Dept., Colorado State University, 75 pp Stevenson PC (1977) An empirical method for the evaluation of relative landslide risk.Int Ass Eng Geol Bull 16:69–72 Varnes DJ (1984) International Association of Engineering Geology Commission on Landslides and Other Mass Movements on Slopes. Landslide hazard zonation: a review of principles and practice. Int Assoc Eng Geol, UNESCO Natural Hazards Series no. 3, 63 pp Vecchia O (1978)A simple terrain index for the stability of hillsides or scarps. In: Geddes JD(ed) Large ground movements and structures. Wiley, NewYork Toronto, pp 449-461 |
Although in most places nearly identical with exactly the same references, no hint is given that this text comes from another source. |
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