Rock Glacier
Abstract Active rock glaciers are the geomorphological expression of creeping mountain permafrost. They consist of a debris–ice mixture that slowly creeps downslope, and they develop therefore a tongue‐shaped or lobate landform with a front scarp and characteristic surface structures such as furrows...
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| Format: | Other/Unknown Material |
| Language: | English |
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Wiley
2004
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| Online Access: | http://dx.doi.org/10.1002/047147844x.sw833 https://onlinelibrary.wiley.com/doi/full-xml/10.1002/047147844X.sw833 https://onlinelibrary.wiley.com/doi/full/10.1002/047147844X.sw833 |
| Summary: | Abstract Active rock glaciers are the geomorphological expression of creeping mountain permafrost. They consist of a debris–ice mixture that slowly creeps downslope, and they develop therefore a tongue‐shaped or lobate landform with a front scarp and characteristic surface structures such as furrows and ridges. The lower limit of rock glacier distribution is associated with the lower limit of mountain permafrost, which is often attributed to the −1 to −2°C isotherm of mean annual air temperature. Unlike “true” glaciers, rock glaciers do not present surface ice or exposed ice in general but contain only supersaturated ground ice, mainly interstitial and segregation ice. Rock glaciers contain between 40 and 60% of ice by volume and constitute therefore unsuspicious stores of water. The amount of water stored within rock glaciers per unit mountain area is one magnitude higher in semiarid mountain areas such as the Andes at 33°S than in the more humid Swiss Alps. |
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