Engineering geomorphology of rock glaciers

A partnership between geomorphology and engineering is facilitating human d evelopment in this harsh environment. Rock glaciers provide locations for u rban water sources, construction borrow sources, drill sites, shaft and tun nel portals, ski tower supports, and dam abutments. Rock glaciers, as dynam ic landforms, necessitate proper identification in the field. Placing struc tures on, in, or adjacent to rock glaciers requires an appreciation and und erstanding of their temporal stability. Internal and surface characteristic s provide important clues to the development and deformation of rock glacie rs. Rock glaciers play a significant role in the alpine debris transport sy stem. Active movement and mass wasting are perhaps the most obvious geologi c hazards affecting engineered works. The structure of the rock glacier is conducive to the production of a steady, continuous supply of meltwater dur ing summer months. Thus, rock glaciers serve as alpine aquifers. Considerat ion of rock glaciers as potential aquifer sources requires caution because of the long-term impact of climate change on the temporal nature of the lan dform. From the rock glaciers that we have monitored for water quality char acteristics, it appears that they provide quality potable water. This paper provides a foundation for appreciation and understanding of rock glaciers from an engineering geomorphologic point of view. The approach taken in thi s paper provides practical, important information to aid the engineer and e ngineering geologist in prudent evaluations of rock glaciers as potential s ites for human development and uses. The bottom line of our paper is: rock glaciers must be avoided for essentially all structures. (C) 1999 Elsevier Science B.V. All rights reserved.