| Title | Current research part C: Canadian Shield / Recherches en cours partie C: Bouclier Canadien |
| Download | Downloads |
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| Licence | Please note the adoption of the Open Government Licence - Canada
supersedes any previous licences. |
| Author | Geological Survey of Canada |
| Source | Geological Survey of Canada, Paper no. 88-1C, 1988, 372 pages, https://doi.org/10.4095/122610  Open Access |
| Image |  |
| Year | 1988 |
| Document | serial |
| Lang. | English; French |
| Media | paper; on-line; digital |
| Related | This publication contains the following
publications |
| File format | pdf |
| Area | Canadian Shield |
| Subjects | metallic minerals; surficial geology/geomorphology; geochemistry; geochronology; radioactive minerals; igneous and metamorphic petrology; mineralogy; structural geology; stratigraphy; economic geology;
geophysics |
| Released | 1988 01 01; 2013 10 17 |
| Abstract | The 1.9 Ga continental rift sediments and volcanic rocks, transitional-crust and true oceanic crust (Purtuniq ophiolite) are contained in thrust sheets bounded by south-verging thrust faults (D 1) and
preserved in the Cape Smith Belt as the result of two post-thrusting episodes (D2, D3) of thick-skinned crustal folding. The D 1 thin-skinned thrustjold belt is characterized by a basal décollement, localized at the basementcover interface, which
displays a frontal ramp that exposes up to 30 m of footwall autochthonous fluviodeltaic sandstone and ironstone. lmbricates of more proximal rift-basin ironstone and sandstone are structurally overlain by more outboard (rift basin) semipelite and
proximal fan arkosic sandstone deposits which pass upwards into LREE-enriched basalts, gabbro sills and minor rhyolite. More internal thrust sheets contain transitional-crust basalts (komatiitic to MORB- like) which are imbricated with distal fan
sandstones and semipelites. Deep water laminated graphitic pelites are structurally sandwiched between underlying transitional-crust basalts and hangingwall ophiolitic units. Imbricates of the ophiolite contain either (1) sheeted dykes overlain by
pillowed and massive basalt flows intruded by mafic dykes and sills; or (2) mafic and ultramafic cumulates. D 1 out-of-sequence thrusting associated with interleaving of basement and caver units, resulted in re-imbrication of the thrust stack and
further southward transport. |
| GEOSCAN ID | 122610 |
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