Rock glaciers Gruben, Muragl and Murtel, Switzerland: Area-wide flow fields  View Catalog Page Entry ID
GGD293
Summary
Besides their thermal and mechanical properties, rock glaciers are essentially defined by their kinematics. Knowledge of the permafrost flow field provides important information about the origin, morphology, development, dynamics and internal structure of creeping mountain permafrost. Monitoring permafrost behavior helps detecting climate signals.
Aerial photogrammetry was used for determining digital terrain models (DTM) with high resolution. The differences of multitemporal DTMs of a rock glacier provide the vertical changes of the permafrost surface. Horizontal surface displacements were obtained by simultaneously comparing two aerial photographs taken at different times and from different positions (Kaeaeb 1996a,b; Kaeaeb et al.1998). Repeated overridings by the nearby glacier affected the upper part of the Gruben rock glacier, Wallis. Compared to the lower, periglacial part of the rock glacier the higher surface lowering rates of the debris-covered dead ice remains indicate the dead ice being out of equilibrium. Due to different internal structure and different slopes, horizontal surface velocities show different creep directions as well as different creep rates. The rock glacier advances by about 12 cm/a. A 25-year time series of photogrammetrical monitoring (1970-1995) documents the temporal variations of surface kinematics of the rock glacier (Kaeaeb et al. 1998a). Surface kinematics of Muragl rock glacier (Upper Engadin) over the period from 1981 to 1994 reveal this rock glacier to be a complex system of several individual streams. Changes in elevation show a pattern of zones of surface heave and subsidence in the range of +- 10 cm/a. The rock glacier advances by about 5 cm/a (Kaeaeb 1998). The velocity field 1987-1996 at the surface of Murtel rock glacier, Upper Engadin, points to two dynamically different parts of the creeping permafrost-- (1) high activity and transverse ridges in the inner part and (2) lower activity at the left and right margins. The ridges are advected down stream with a velocity approximately equal to the surface velocity. Stream lines can be interpolated from the surface velocity field. The curvature of the isochrones on Murtel rock glacier is similar to the curvature of the transverse ridges, which suggests slow changes in the flow field (Kaeaeb 1998, Kaeaeb et al. 1998b). These data are presented on the CAPS Version 1.0 CD-ROM, June 1998.
Geographic Coverage
Spatial Coordinates:
N: 46.506°
S: 46.169°
E: 9.933°
W: 7.964°
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Data Set Citation
Dataset Creator: Kaeaeb, A
Dataset Title: Rock glaciers Gruben, Muragl and Murtel, Switzerland: Area-wide flow fields
Dataset Release Date: 1998-01-01
Dataset Release Place: Boulder, Colorado USA
Dataset Publisher: NSIDC: National Snow and Ice Data Center
Online Resource: http://nsidc.org/data/ggd293.html
Temporal Coverage
Start Date: 1970-01-01
Stop Date: 1994-12-31
Location Keywords
- CONTINENT EUROPE WESTERN EUROPE SWITZERLAND SAAS VALLEY, VALAIS ALPS; UPPER ENGADINE, SWITZERLAND
Science Keywords
- Cryosphere Frozen Ground Periglacial Processes
- Cryosphere Frozen Ground Permafrost Mountain Permafrost
- Cryosphere Frozen Ground Rock Glaciers
- Land Surface Frozen Ground Periglacial Processes
- Land Surface Frozen Ground Permafrost Mountain Permafrost
- Land Surface Frozen Ground Rock Glaciers
Ancillary Keywords
- Permafrost Properties
- Remote Sensing
- Rock Glaciers
- Slope Processes
Data Center
National Snow and Ice Data Center
Data Center URL: http://nsidc.org
Data Center Personnel
Name: NSIDC User Services
Phone: 1 303 492-6199
Fax: 1 303 492-2468
Email: nsidc@nsidc.org
Contact Address:
- National Snow and Ice Data Center
- CIRES, 449 UCB
- University of Colorado
City: Boulder
Province or State: CO
Postal Code: 80309-0449
Country: USA
NSIDC Frozen Ground Data Center
Data Center URL: http://nsidc.org/fgdc/
Data Center Personnel
Name: NSIDC FGDC User Services
Phone: 1 303 492-6199
Fax: 1 303 492-2468
Email: nsidc@nsidc.org
Contact Address:
- National Snow and Ice Data Center
- CIRES, 449 UCB
- University of Colorado
City: Boulder
Province or State: CO
Postal Code: 80309-0449
Country: USA
Personnel
Andreas Kaeaeb
Role: INVESTIGATOR
Phone: 41 1 6355146
Fax: 41 1 635 6848
Email: kaeaeb@geo.unizh.ch
Contact Address:
- University of Zurich-Irchel
- Department of Geography, Physical Geography Division
- Winterthurerstr. 190
City: Zurich
Postal Code: CH-8057
Country: Switzerland
Metadata Name and Version
Metadata Name: CEOS IDN DIF
Metadata Version: 9.7
Creation and Review Dates
DIF Creation Date: 1998-01-01
Last DIF Revision Date: 2012-08-29
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