| Title | Structural reconnaissance of a deep crustal orogen using RADARSAT and Landsat satellite imagery and airborne geophysics |
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| Author | Rivard, B; Corriveau, L ; Harris, L B |
| Source | Canadian Journal of Remote Sensing 25, 3, 1999 p. 258-267, https://doi.org/10.1080/07038992.1999.10874724 |
| Year | 1999 |
| Alt Series | Geological Survey of Canada, Contribution Series 1998271 |
| Publisher | Informa UK Limited |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | Quebec |
| NTS | 31G/09; 31G/10; 31G/11; 31G/12; 31G/13; 31G/14; 31G/15; 31G/16; 31J |
| Area | Mont Laurier |
| Lat/Long WENS | -76.0000 -74.0000 47.0000 45.5000 |
| Subjects | structural geology; geophysics; crustal studies; crustal evolution; crustal structure; orogenesis; satellite imagery; magnetic surveys, airborne; remote sensing; structural features; folds; faults;
Central Metasedimentary Belt |
| Illustrations | sketch maps; satellite images |
| Released | 2014 07 31 |
| Abstract | (Summary)
Understanding crustal evolution through studies of highly eroded orogens is a current scientific challenge worldwide. The marble and quartzite sequences and gneiss complexes of the
Mont-Laurier area, in the Central Metasedimentary Belt of Quebec, form a collage of rheologically contrasting lithotectonic domains affected by successive orogenic and magmatic events. Landsat and RADARSAT satellite imagery, with their synoptic view
and geomorphic detail, are well suited for the study of structurally complex terrains, especially when image analysis is integrated with regional field and geophysical data. For the Mont-Laurier area, the interpretations of such imagery led to the
delineation of intrusive bodies, zones of ductile deformation, and fold interference patterns allowing refinements of existing 1: 50 000 maps and providing key information for reconnaissance mapping. The gneiss complexes record early Grenvillian
convergence (pre-1.19 Ga) and display a highly contorted distribution of lithologies due to multiple fold interference patterns. On radar and Landsat imagery the complexes are relatively featureless structurally, due to the complex foliation
trajectories and the small wavelength of folds. Greater success was obtained for similar structures, in gneisses of the quartzite domain, due to the larger amplitude of folds. Landsat TM band 4 imagery outlines the competency contrast of quartzite
versus marble and can be used to map the domain of marble. At 1.165 Ga emplacement of the Chevreuil intrusive suite, concentrated along N-S corridors, marked the onset of renewed orogenic activity. Many of the intrusions from this suite have a unique
topographic signature which can be delineated on the Landsat and RADARSAT imagery. Following the magmatic activity, late compressive deformation in the ductile regime was focused along the N-S corridors. The style of this deformation is characterized
by a regional N-S foliation and coaxial anastamozing shear zones (NE-SW dextral; NW-SE sinistral) which were delineated in the radar imagery and confirmed using field kinematic indicators. The RADARSAT imagery provides a view of the extent of this
deformation event and corroborates field and petrological studies indicating that by 1.165 Ga, the gneiss complexes were mechanically strong trustai domains and were only locally overprinted by late-stage ductile deformation. |
| GEOSCAN ID | 210303 |
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