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Natural Resources Canada > Earth Sciences Sector > Priorities > Sustainable development of natural resources > Consolidating Canada's geoscience knowledge > Scotian Margin
Geology of the Scotian Margin Crustal structure: New seismic data
Location of seismic profiles |
| Description of lines 1,2,3 |
- Length: 489 km
Shots: 3691
Receivers: 19
Interpretation summary:
Up to 15 km of syn- and post-rift sediments overlie thinned continental crust seaward of the hinge zone. A 145-km wide zone with P-wave velocities of 7.2 to 7.6 km/s separates thinned continental crust from oceanic crust. This zone is interpreted as partially serpentinized mantle, overlain by highly altered and thinned continental crust in the NW and by highly serpentinized mantle (velocity 5.1 km/s) in the SE.
(after Funck et al. 2003, EGS/AGU/EUG abstract)
- Length: 491 km
Shots: 3643
Receivers: 21
Interpretation summary:
Thinned continental crust extends for 180 km beneath a highly faulted basement structure. A 120-km wide region of partially serpentinized mantle is interpreted within the ocean-continent transition zone. The velocity model shows no evidence for a magmatic underplated layer beneath the continental crust, and the source of the reduced amplitude ECMA in this region is uncertain.
(after Wu et al. 2004, AGU/CGU/SEG abstract)
- Length: 282 km
Shots: 2193
Receivers: 12
Interpretation summary:
A 120 km-wide transition zone separates thinned continental crust from oceanic crust. P-wave velocities in the transition zone average 6.2 (upper) and 7.2 km/s (lower layer), consistent with velocities for the transition zone off the US Atlantic margin where the volcanic nature has been well-established. The location of the transitional crust is coincident with seismic SDRs and the ECMA . magnetic models also support an interpretation of volcanic origin. Total thickness of the transitional crust is only 10 km, significantly thinner than the interpreted igneous layers of the US Atlantic margin.
(after Dehler et al. 2004, AGU/CGU/SEG abstract)
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