A Late Pennsylvanian Ammonoid From Ellesmere Island, Canadian Arctic Archipelago

1969 ◽  
Author(s):  
W W Nassichuk
Polar Record ◽  
1993 ◽  
Vol 29 (171) ◽  
pp. 277-304 ◽  
Author(s):  
William Barr

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.


1975 ◽  
Vol 12 (1) ◽  
pp. 90-94 ◽  
Author(s):  
A. K. Sinha ◽  
Thomas Frisch

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.


2007 ◽  
Vol 44 (7) ◽  
pp. 1005-1013 ◽  
Author(s):  
Karsten Piepjohn ◽  
Solveig Estrada ◽  
Lutz Reinhardt ◽  
Werner von Gosen ◽  
Harald Andruleit

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.


1993 ◽  
Vol 30 (4) ◽  
pp. 867-880 ◽  
Author(s):  
Eva M. Klaper ◽  
Yoshihide Ohta

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.


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