| Title | Metamorphic and plutonic rocks of northernmost Ellesmere Island, Canadian Arctic Archipelago |
| Download | Downloads |
| Author | Frisch, T |
| Source | Geological Survey of Canada, Bulletin 229, 1974, 87 pages (1 sheet), https://doi.org/10.4095/103478 |
| Year | 1974 |
| Publisher | Geological Survey of Canada |
| Document | serial |
| Lang. | English |
| Maps | Publication contains 1 map |
| Map Info. | geological, 1:250,000 |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | Nunavut |
| NTS | 340E; 340E; 340E; 340E; 340E; 340E; 340F/02; 340F/03SW; 340F/03NW; 340F/04SE; 340F/04NE; 340F/07; 340F/08; 340F/09; 340F/10; 340F/16; 120F/13; 120G/04 |
| Area | Ellesmere Island |
| Lat/Long WENS | -87.0000 -70.0000 83.2500 82.0000 |
| Subjects | structural geology; chemical analyses; modal analyses; petrography; plutonic rocks; Cornwallis Fold Belt; Ellesmere Fold Belt; Parry Islands Fold Belt; Sverdrup Basin |
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| Released | 1974 11 01; 2015 12 17 |
| Abstract | Information obtained from reconnaissance mapping between Cape Aldrich and Phillips Inlet has resulted in an extension of previously defined limits of areas underlain by metamorphic and plutonic rocks in
the Northern Ellesmere Fold Belt of the Franklinian Geosyncline. Metamorphic rocks are most abundant between M'Clintock and Phillips Inlets; they occur in lesser amount between Cape Aldrich and M'Clintock Inlet. Amphibolite facies gneisses and
schists tend to be restricted to the northernmost coasts, whereas greenschist facies rocks form extensive terrains inland. Metamorphism appears to have been of Barrovian type and the highest grade exposed is that of the kyanite zone. Retrogressive
metamorphism, promoted by cataclasis, was particularly pronounced in the Cape Columbia area. Three new K/ Ar age determinations on metamorphic rocks from the Cape Columbia area yield Middle Ordovician to Early Devonian dates but field evidence
indicates that at least part of the northern Ellesmere metamorphic complex is of preMiddle Ordovician age. Possible remobilization of metamorphic basement on Ayles Fiord in mid-Paleozoic time is suggested by a new K/ Ar age determination. Plutonic
activity appears to have been particularly active in Early Devonian time. A deformed, partly layered gabbro-peridotite body of tholeiitic affi nity has intruded metamorphic rocks at Cape Fanshawe Martin. A K/ Ar age determination on biotite from the
intrusion indicates 376 ± 16 m.y. as a minimum age of crystallization. Two alpine-type serpentinite massifs occur near the head of M'Clintock Inlet and were intruded by small felsic sheets and plugs, one of which has been dated (hornblende K/ Ar) at
390 ± 18 m.y. South of Cape Richards, a zoned complex of alkalic syenite bordered by quartz monzonite has intruded pre-Middle Ordovician metamorphic rocks. A hornblende K/ Ar date of 390 ± 18 m.y. for the quartz monzonite probably gives a reliable
minimum age of crystallizat ion. A granitic pluton (biotite K/ Ar age 345 ± 15 m.y.) at the mouth of Phillips Inlet is bordered by a narrow, staurolite-kyanite-si llimanite-bearing contact aureole and is probably related to nearby smaller felsic
plutons (biotite K/ Ar age : 325 ± 14 m.y.), which earlier have been interpreted to be mesozonal to epizonal intrusions emplaced during a Middle Devonian to Mississippian orogeny.
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| GEOSCAN ID | 103478 |
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