In recent years, the study of rock glaciers has increased remarkably. Substantiveprogress has been made, particularly in understanding the formation of rockglaciers that have developed adjacent to existing or former valley or cirqueglaciers, However, our understanding of valley-wall rock glaciers that arelocated at the base of talus slopes remains scant. Published work exhibits littleconsensus on the formation of valley-wall rock glaciers and several hypothesesremain under vigorous debate. The major objective of the research reported inthis thesis has been to test the generality and feasibility of seven major modelsof valley-wall rock glacier formation using both empirical and theoreticalevidence. The primary conclusion is that only one of these models, thesegregation ice model, emerges as a general model of valley-wall rock glaciergenesis. The model assumes that a thin layer or several thin layers ofsegregated ice are overlain by interstitially frozen sediments and an unfrozenmantle of coarse debris. A wide range of empirical and theoretical findings areshown to be consistent with the implications of the segregation ice model.Detailed observations on the morphology, sedimentology and distribution ofactive, inactive and relict valley-wall rock glaciers studied in Switzerland,northern Norway and Scotland provided a range of findings that support thismodel. Theoretical evidence was obtained by modelling a number of differentdensity models that reflect different distribution of internal ice by applying asimple laminar flow equation to field measurements. Although only thesegregation ice model appears to be valid at a general level, the possibilitycannot be excluded of alternative modes of valley-wall rock glacier formationunder particular circumstances. Snow avalanching, deformation of snowbankor matrix ice, and basal sliding under conditions of high hydrostatic pressure allconstitute possible contributing mechanisms of formation and movement inparticular cases.
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