Whole-Rock Rb/Sr Ages of Metamorphic Rocks from Northern Ellesmere Island, Canadian Arctic Archipelago. I. The Gneiss Terrain between Ayles Fiord and Yelverton Inlet

1975 ◽  
Vol 12 (1) ◽  
pp. 90-94 ◽  
Author(s):  
A. K. Sinha ◽  
Thomas Frisch
Keyword(s):  
Regional Metamorphism ◽  
Canadian Arctic ◽  
Ellesmere Island ◽  
Metamorphic Rocks ◽  
Canadian Arctic Archipelago ◽  
Fold Belt ◽  
Late Precambrian

The first Precambrian ages from the Northern Ellesmere Fold Belt are reported. Six rocks from the largest gneiss terrain in northern Ellesmere Island yield a Late Precambrian age (minimum 742 ± 12 m.y.) of regional metamorphism. Relatively high initial 87Sr/86Sr suggests that the rocks were derived from crustal materials.

Whole-rock Rb/Sr and zircon U/Pb ages of metamorphic rocks from northern Ellesmere Island, Canadian Arctic Archipelago. II. The Cape Columbia Complex

1976 ◽  
Vol 13 (6) ◽  
pp. 774-780 ◽  
Author(s):  
A. K. Sinha ◽  
Thomas Frisch
Keyword(s):  
North Atlantic ◽  
Age Groups ◽  
Canadian Arctic ◽  
Ellesmere Island ◽  
Metamorphic Rocks ◽  
Canadian Arctic Archipelago ◽  
Fold Belt ◽  
The North ◽  
The North Atlantic ◽  
North Atlantic Craton

Although not clearly separable on field and petrographic criteria, the gneisses of the Cape Columbia Complex, one of the two major crystalline terrains in the Northern Ellesmere Fold Belt, fall into two Rb/Sr age groups: nine samples define an isochron corresponding to an age of 1083 ± 18 m.y., Sr0 = 0.7057, while six samples show more scatter at 512 ± 90 m.y.,Sr0 = 0.7189. Zircons from two gneisses have 207Pb/206Pb, i.e. minimum, ages of 926 and 980 m.y. These data are interpreted as indicating that the rocks were recrystallized in the amphibolite facies about 1000 m.y. ago; little significance is attached to the younger Rb/Sr age. However, the possibility that the rocks are orthogneisses emplaced about 1000 m.y. ago and subsequently metamorphosed ~500–600 m.y. ago, cannot be excluded. In any event, the Cape Columbia Complex becomes the latest addition to the growing list of occurrences of 900–1200 m.y.-old ('Grenville-Sveco-Norwegian') rocks in the North Atlantic craton and environs.

Paleozoic metamorphism across the boundary between the Clements Markham fold belt and the Pearya terrane in northern Ellesmere Island, Canadian Arctic Archipelago

1993 ◽  
Vol 30 (4) ◽  
pp. 867-880 ◽  
Author(s):  
Eva M. Klaper ◽  
Yoshihide Ohta
Keyword(s):  
Invariant Point ◽  
Sedimentary Rocks ◽  
Canadian Arctic ◽  
Boundary Region ◽  
Ellesmere Island ◽  
Canadian Arctic Archipelago ◽  
Fold Belt ◽  
Garnet Porphyroblasts ◽  
Single Episode ◽  
Differential Uplift

Microstructural and petrological data suggest that a single episode of syn- to post-tectonic metamorphism affected the boundary region between the Clements Markham fold belt and Pearya, a postulated Caledonian terrane, during a mid-Paleozoic orogenic event in northern Ellesmere Island. The sedimentary rocks of the Clements Markham fold belt pass from chlorite to biotite to garnet grade over a distance of about 10 km as the contact with the Mitchell Point belt gneisses of Pearya is approached from the south. Foliation development and chevron-style folding was followed by the growth of the index minerals chlorite, biotite, chloritoid, garnet, staurolite, and kyanite in semipelitic rocks in four metamorphic zones. Thermobarometry of garnet porphyroblasts indicates peak metamorphic conditions of about 600 °C and 600 MPa in the highest grade rocks. Chloritoid-involving phase relations define an invariant point at 540 °C and 500 MPa only 2 km away from the highest grade zone. It may be concluded from the calculated pressure and temperature differences over this short distance that the isogradic surfaces of the post-chevron-folding metamorphism are steeply oriented. Much of the observed metamorphic pattern can, therefore, be explained as the result of a significant post-chevron-folding differential uplift (overthrusting) of the hot Mitchell Point belt gneisses relative to the Clements Markham fold belt. This indicates that the Mitchell Point belt forms a thrust sheet which overlies the Clements Markham fold belt and that the accretion of Pearya predates the Late Silurian.

The career and disappearance of Hans K.E. Krüger, Arctic geologist, 1886–1930

Polar Record ◽  
1993 ◽  
Vol 29 (171) ◽  
pp. 277-304 ◽  
Author(s):  
William Barr
Keyword(s):  
Continental Shelf ◽  
Canadian Arctic ◽  
Field Work ◽  
Ellesmere Island ◽  
Canadian Arctic Archipelago ◽  
Royal Canadian Mounted Police ◽  
West Greenland

ABSTRACTOn 19 March 1930 the German geologist, Hans K.E. Krüger, accompanied by a Dane, Åge Rose Bjare, and an Inughuk, Akqioq (the latter driving their dog sledge) set off westwards from the Royal Canadian Mounted Police post at Bache Peninsula, Ellesmere Island; two support sledges, driven by Inughuit, escorted them. It appears to have been Krüger's intention to study the geology of the coasts of the outer islands of the Canadian Arctic archipelago and to carry out soundings of the continental shelf and slope. The two support sledges turned back at Depot Point, Eureka Sound. Krüger, Bjare, and Akqioq were never seen again. This article reviews Krüger's background, his preparations for the expedition (which included two summers of field work in West Greenland and a wintering in northwest Greenland), and the extensive searches mounted by the RCMP in 1931 and 1932. Finally, it analyzes the evidence provided by three messages left by Krüger and subsequently recovered, with a view to making an educated guess as to the fate of the expedition.

Deciphering superimposed Ellesmerian and Eurekan deformation, Piper Pass area, northern Ellesmere Island (Nunavut)

2007 ◽  
Vol 44 (10) ◽  
pp. 1439-1452 ◽  
Author(s):  
Karsten Piepjohn ◽  
Werner von Gosen ◽  
Solveig Estrada ◽  
Franz Tessensohn
Keyword(s):  
Fault Zone ◽  
Tectonic Evolution ◽  
Canadian Arctic ◽  
Ellesmere Island ◽  
Thrust Faults ◽  
Fold Belt ◽  
Sverdrup Basin

The tectonic evolution in the Piper Pass area in northern Ellesmere Island (Canadian Arctic) is characterized by the superimposition of two major deformational events: the Paleozoic Ellesmerian Orogeny and the Tertiary Eurekan deformation. It is difficult to separate the structures formed during each deformation in the parts of the Canadian Arctic in which the post-Ellesmerian and pre-Eurekan Sverdrup Basin is not preserved (Hazen Fold Belt, Central Ellesmere Fold Belt). In the vicinity of the Lake Hazen Fault Zone in the Piper Pass area, kilometre-scale kink folds, cleavage planes and SSE-directed thrust faults are unconformably overlain by Permian through Tertiary rocks of the Sverdrup Basin, which clearly indicates that they are related to the Ellesmerian Orogeny. However, the steep faults of the Lake Hazen Fault Zone are characterized by possible lateral movements and by NNW–SSE compression that cut through or affect both the pre-Ellesmerian Franklinian strata, as well as the post-Ellesmerian Sverdrup Basin deposits. These structures can clearly be assigned to post-mid Cretaceous movements of the Eurekan deformation. The Piper Pass area is a key area in which it is possible to recognize and distinguish Ellesmerian from Eurekan structures.

Origin of iron-oxide and silicate melt rocks in Paleogene sediments of southern Ellesmere Island, Canadian Arctic Archipelago, Nunavut

2007 ◽  
Vol 44 (7) ◽  
pp. 1005-1013 ◽  
Author(s):  
Karsten Piepjohn ◽  
Solveig Estrada ◽  
Lutz Reinhardt ◽  
Werner von Gosen ◽  
Harald Andruleit
Keyword(s):  
Canadian Arctic ◽  
Ellesmere Island ◽  
Anthropogenic Activity ◽  
Canadian Arctic Archipelago ◽  
X Ray Diffraction ◽  
Coal Seams ◽  
Volcanic Origin ◽  
X Ray ◽  
Early Tertiary ◽  
Unconsolidated Sand

Between Vendom Fiord and Makinson Inlet on southern Ellesmere Island, Canadian Arctic Archipelago, Nunavut, isolated and fault-bounded Early Tertiary basins are exposed. The basin deposits are Paleocene to Eocene in age and overlie unconformably folded Ordovician and Silurian carbonates of the Paleozoic Franklinian Basin that were affected by intense, pre-Paleocene weathering and karstification in places. The Tertiary sediments consist mainly of dark unconsolidated sand and silt and are interbedded with many centimetre- to metre-thick coal seams. In several places, round orange and red "spots" occur within the dark grey Tertiary basin fills and are clustered on top of the dark grey Tertiary occurrences. The "spots" are up to 100 m in diameter and consist of consolidated burnt shards of clay or clinker. In the centre of the reddish "spots," dark, massive, and partly high-magnetic lava- or slag-like rocks are poorly exposed as masses that are a decimetre or less in scale. These rocks were investigated using thin section studies, as well as X-ray diffraction and X-ray flourescence analyses. The melt rocks are composed of glass, cordierite-group minerals, hematite, magnetite, tridymite, mullite, and cristobalite. They represent paralavas resulting from subsurface combustion of the Tertiary coal seams under conditions similar to those in a blast furnace. An origin by anthropogenic activity or a volcanic origin can be ruled out.

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