| Titre | Geophysical investigation and InSAR mapping of permafrost and ground movement at the airport of Iqaluit |
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| Auteur | LeBlanc, A -M ;
Short, N; Oldenborger, G A; Mathon-Dufour, V; Allard, M |
| Source | Cold regions engineering 2012: Sustainable infrastructure development in a changing cold environment, ASCE 2012; 2012 p. 644-654 |
| Image |  |
| Année | 2012 |
| Séries alt. | Secteur des sciences de la Terre, Contribution externe 20120038 |
| Réunion | 15th International Conference on Cold Regions Engineering; Quebec; CA; août 19-22, 2012 |
| Document | livre |
| Lang. | anglais |
| Media | papier |
| Province | Nunavut |
| SNRC | 25N/10 |
| Région | Iqaluit; île de Baffin |
| Lat/Long OENS | -68.5667 -68.5333 63.7667 63.7333 |
| Sujets | télédétection; pergélisol; glace fossile; levés géophysiques; géoradar; résistivité électrique; interpretations de résistivité; stabilité des pentes; géophysique; géologie des dépôts
meubles/géomorphologie; géologie de l'ingénieur; Nature et environnement |
| Illustrations | cartes de localisation; photographies |
| Programme | Géosciences de changements climatiques |
| Résumé | (disponible en anglais seulement)
The history of Iqaluit airport has been punctuated with noticeable settlement and frost cracking problems affecting the asphalt and the embankments. In order to
characterize the permafrost conditions on which the performance of the engineering infrastructure depends, field campaigns were conducted and combined with remote sensing data. Electrical resistivity imaging (ERI) and ground penetrating radar (GPR)
surveys were used to support surface observations made in the field and from air photos and provide extended spatial and vertical knowledge. The interferometric synthetic aperture radar (InSAR) mapping provided short term ground surface movement
information. Interpretation from the GPR profile suggests the presence of ice wedges below the embankment that are associated with some of the settlement and frost cracking problems affecting the runway. Based on the geophysical interpretation, the
thawing front, around a depth of 3 m, has reached the natural ground, and therefore, settlement due to melting ice wedges will probably continue. ERI also revealed a large-scale conductive anomaly at a depth of approximately 6 m below the asphalted
surface of the runway and this feature might eventually lead to settlement problems. Within this area, the InSAR map showed greater downward ground surface movement over the course of one summer than the surrounding areas, with values around 4.5 and
6.6 cm. In general and at the scale of the InSAR data, the runway embankment shoulders appear quite stable. Although the InSAR data provided a good correlation with the terrain units, the ground truth measurements have shown slightly higher values of
downward movement. |
| GEOSCAN ID | 291407 |
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