Otto Fiord Research Articles

Exposed evaporite diapirs and minibasins above a canopy in central Sverdrup Basin, Axel Heiberg Island, Arctic Canada

AbstractAxel Heiberg Island (Arctic Archipelago, northern Nunavut, Canada) contains the thickest Mesozoic section in Sverdrup Basin (11 km). The ca. 370‐km‐long island is second only to Iran in its concentration of exposed evaporite diapirs. Forty‐six diapirs of Carboniferous evaporites and associated minibasins are excellently exposed on the island. Regional anticlines, which formed during Paleogene Eurekan orogeny, trend roughly north on a regular ca. 20‐km wavelength and probably detach on autochthonous Carboniferous Otto Fiord Formation evaporites comprising halite overlain by thick anhydrite. In contrast, a 60‐km‐wide area, known as the wall‐and‐basin structure (WABS) province, has bimodal fold trends and irregular (<10 km) wavelengths. Here, crooked, narrow diapirs of superficially gypsified anhydrite crop out in tight anticline cores, which are separated by wider synclinal minibasins. We interpret the WABS province to detach on a shallow, partly exposed canopy of coalesced allochthonous evaporite sheets. Surrounding strata record a salt‐tectonic history spanning the Late Triassic (Norian) to the Paleogene. Stratigraphic thinning against diapirs and spectacular angular unconformities indicate mild regional shortening in which diapiric roof strata were bulged up and flanking strata steepened. This bulging culminated in the Hauterivian, when diapiric evaporites broke out and coalesced to form a canopy. As the inferred canopy was buried, it yielded second‐generation diapirs, which rose between minibasins subsiding into the canopy. Consistent high level emplacement suggests that all exposed diapirs inside the WABS area rose from the canopy. In contrast, diapirs along the WABS margins were sourced in autochthonous salt as first‐generation diapirs. Apart from the large diapir‐flanking unconformities, Jurassic‐Cretaceous depositional evidence of salt tectonics also includes submarine debris flows and boulder conglomerates shed from at least three emergent diapirs. Extreme local relief, tectonic slide blocks, steep talus fans and subaerial debris flows suggest that many WABS diapirs continue to rise today. The Axel Heiberg canopy is one of only three known exposed evaporite canopies, each inferred or known at a different structural level: above the canopy (Axel Heiberg), through the canopy (Great Kavir) and beneath a possible canopy (Sivas).

An Unusual Occurrence of Bashkirian (Pennsylvanian) Rugose Corals From the Sverdrup Basin, Arctic Canada

The oldest known Carboniferous rugose coral fauna in the Canadian Arctic Islands was collected in the Yelverton Inlet area of northern Ellesmere Island, from Bashkirian carbonates of the lower Nansen and Otto Fiord formations. It includes the generaDibunophyllumThomson and Nicholson,LonsdaleiaMcCoy,PalaeosmiliaMilne-Edwards and Haime andTizraia? Said and Rodríguez. Such a generic assemblage is unknown elsewhere above the Serpukhovian. An upper? Bashkirian specimen ofParaheritschioidesSando, collected above the main fauna, is the oldest known representative of that genus. Faunal comparisons suggest Novaya Zemlya or northern Timan as the most likely source areas for the Yelverton Inlet fauna.

An allochthonous salt canopy on Axel Heiberg Island, Sverdrup Basin, Arctic Canada

Axel Heiberg Island (northern Nunavut) contains the thickest Mesozoic section in the Sverdrup Basin. The ∼370-km-long island is second only to Iran in its concentration of exposed evaporite diapirs. However, the tectonics of this remote region is not well known. A polar desert on the island provides excellent exposure of 46 diapirs of Carboniferous evaporites and associated minibasins. Paleogene (Eurekan) anticlines trend roughly north on a regular ∼20 km wavelength and probably detach on autochthonous Carboniferous Otto Fiord evaporites. In contrast, a 60-km-wide area, known as the wall-and-basin structure (WABS) province, has bimodal fold trends and irregular wavelengths of <10 km. Here, crooked walls of diapiric anhydrite crop out in the cores of tight anticlines. Wider synclinal minibasins separate the diapiric walls. We interpret the WABS province to detach on a shallow evaporite canopy. This comprises an allochthonous coalescence of evaporite diapirs that spread extrusively during the Hauterivian (Early Cretaceous, ca. 130 Ma), close to the onset of seafloor spreading in the Arctic Ocean and of flood basalt volcanism associated with Alpha Ridge. Since then, the evaporite canopy has yielded second-generation diapirs, now exhumed and exposed by modest Eurekan shortening. Strata record minibasin evolution and diapirism since at least the Late Triassic. Stratigraphic thinning against diapirs and spectacular angular unconformities at four levels are present between the Jurassic and Paleocene. The most widespread is the Early Cretaceous event marking the time of canopy emplacement. Outcrops record the later fate of the canopy, including exposure, onlap of diapirs, and off-diapir debris flows.

Glacial advances and stratigraphy in Otto Fiord and adjacent areas, Ellesmere Island, Northwest Territories

Hvitland and Svartfjeld peninsulas have been glaciated at least two or three times since the Late Pliocene. The earliest recognized glaciation is constrained by amino acid ratios on in situ pelecypods from marine sediments stratigraphically overlying till in Otto Fiord. High amino acid ratios suggest that the shells may be Pliocene and related to recently discovered Late Pliocene Hvitland beds at White Point. The same samples yielded finite radiocarbon ages in the 30.2–34.8 ka BP range, which cautions against their acceptance. A second, mid Quaternary glaciation is suggested by intermediate amino acid ratios from in situ pelecypods and shell-bearing till covering coastal uplands along Nansen Sound. During the last glaciation the peninsula was covered by coalesced ice caps, with glacial tongues descending tributary valleys and extending into the fiords. Deglaciation of a tributary valley in outer Otto Fiord proceeded before 11.6 ka BP and before 9.1 ka BP in mid Otto Fiord, but major ice margins remained at the coast until 8–8.5 ka BP. Lateral meltwater channels record systematic ice retreat up tributary valleys into the interior of the peninsulas. The highest recognized marine limits are marked by prominent deltas at least 164 m asl on western Hvitland Peninsula. The marine limit declines eastward inside Otto, Jugeborg, and Hare fiords. The highest strandlines could not be dated; however, by ~8.3 ka BP relative sea level stood at 103 m asl.

The Demise of Sverdrup Basin: Late Cretaceous-Paleogene Sequence Stratigraphy and Forward Modeling

ABSTRACT Five third-order stratigraphic sequences comprising Upper Cretaceous-Paleogene successions on Ellesmere and Axel Heiberg islands (Kanguk Formation and Eureka Sound Group) record fundamental changes in the mechanisms of subsidence and the ultimate demise of Sverdrup Basin. Sequence I (Cenomanian-Maastrichtian) represents a continuation of typical Sverdrup sedimentation patterns (delta and associated facies), and long-lived, thermally controlled subsidence where sedimentation rates averaged 3 cm/ky. Relative fall of base level at the end of the Cretaceous resulted in n basinwide sub-Paleocene unconformity, below which some or all Maastrichtian strata were removed. This event coincided with changes in sea-floor spreading in Canada Basin and northern Labrador Sea, and rejuvenation of volc nism along the northern basin margin. Foredeep-like subsidence and sedimentation began in the Paleogene. Subsidence was caused by compression and crustal buckling associated with shortening between Greenland and Arctic North America rather than by tectonically emplaced vertical loads. Accordingly, Sequences 2 to 4 (Paleocene-Middle Eocene) record significant increases in subsidence and sedimentation rates in the basin. Deposition in the preorogenic Sverdrup Basin culminated with Sequence 4 (Late Paleocene-Middle Eocene), the basin being filled to sea level. Basin size, and sedimentation rates that averaged 15 cm/ky but sometimes were as high as 20-40 cm/ky, were greatest during deposition of Sequences 3 and 4. Syntectonic conglomerate appears locally in Early Eocene fault-b unded basins (Sequence 4--Otto Fiord and Emma Fiord). Nevertheless, the preorogenic basin survived as a subsiding entity until Middle Eocene time, despite the local deformation. Increased shortening and crustal failure during Middle Eocene time eventually fragmented the Sverdrup Basin into narrow, syntectonic intermontane basins (Sequence 5), marking its demise.

First Landsat multi-spectral scanner images of the Canadian Arctic north of 80°N

AbstractLandsat images of northern Axel Heiberg Island and northern Ellesmere Island, including part of the Ellesmere Island National Park Reserve in the Canadian high Arctic, are presented. These are believed to be the first Landsat images ever to be obtained of this region, which is north of latitude 80°N and once thought to be beyond the meaningful imaging range of Landsat. A general description of glaciological phenomena in the almost cloud-free images, and some of the attributes of the Ellesmere Island National Park Reserve, demonstrates some of the features and processes that can be imaged by Landsat in the region. New findings concerning the state and position of the front of the surge-type Otto Glacier, icebergs in Otto Fiord, and the extent and surface morphology of the Nansen Ice Plug indicate the capabilities of Landsat to contribute to original glaciological research in the region.

Carbonate-Anhydrite Facies Relations in Otto Fiord Formation (Mississippian-Pennsylvanian), Canadian Arctic Archipelago

The Otto Fiord Formation is a major evaporite deposit of Late Mississippian to Middle Pennsylvanian age occupying an axial position in the Sverdrup basin of the Canadian Arctic Archipelago. Where exposed in normal stratigraphic succession on northwestern Ellesmere Island, the Otto Fiord is composed of 350 to 600 m of rhythmically alternating limestone and anhydrite, with some interbedded sandstones near the top of the formation. The formation is underlain by continental to marginal-marine red beds, and is overlain by carbonate rocks and shales of deep-water aspect. Laterally, the Otto Fiord evaporites and limestones are coeval with marine-shelf carbonate rocks that flank the margins of the evaporite-carbonate basin. In the central and southern Sverdrup basin, a salt and anhydrite facies of the Otto Fiord is buried by thick Mesozoic rocks and is revealed at the surface only in large diapiric structures. At several localities on northwestern Ellesmere Island, limestone mounds are enclosed within the Otto Fiord Formation. At van Hauen Pass, mounds up to 30 m thick and 350 m long are built on erosional remnants of anhydrite. The mounds have a crinoid-rich marine limestone base, a main beresellid algal-buildup facies of hypersaline aspect, and several marine-limestone capping beds. Each of the marine-limestone phases has thin, marine-limestone equivalents in the intermound setting, each separated by a unit of anhydrite. Reconstructions of depositional events reveal that the mounds are the composite record of at least three transgressive-regressive cycles in which carbonate sediment was deposited during the marine phase and the algal facies and anhydrite units were formed under the hypersaline conditions imposed by evaporitic drawdown. At a facies transition from Otto Fiord evaporites to the basin-margin reef and shelf carbonate rocks exposed on northwestern Ellesmere Island, anhydrite units are interbedded with limestones at the foot of steeply dipping shelf-foreslope carbonate tongues. Depositional relief on these carbonate units increases upward through the evaporite succession from a few meters to more than 400 m. Anhydrite units interbedded with the limestones apparently formed subaqueously under conditions of depressed hypersaline sea level, probably shallower than the depths suggested by carbonate depositional relief, but far from a sabkhalike environment. The accumulated evidence supports earlier interpretations that the anhydrite evaporites of the Otto Fiord Formation were deposited in a hypersaline subaqueous environment under conditions of regional evaporative drawdown of sea level. The complex facies relations demonstrated by the Otto Fiord rocks may serve as guides for modeling evaporite-reef relations and major carbonate to evaporite-facies transitions in other basins and in subsurface studies related to hydrocarbon exploration.

Sulphates of Submarine Origin in Pennsylvanian Otto Fiord Formation of Canadian Arctic

ABSTRACT The Pennsylvanian Otto Fiord Formation in the Hare Fiord area, Ellesmere Island, is a succession of interbedded limestone, anhydrite and minor clastics of over 600 m thickness. Ancient anhydrite deposits have been widely assigned to supratidal or sabkha environments largely by analogy with the well-known Trucial coast sabkhas. Further, it is commonly held that in basinal environments precipitated sulphate will not accumulate as extensive deposits because of sulphate reduction in the presence of organic matter. The Otto Fiord Formation provides an example of a thick calcium sulphate deposit which apparently accumulated in a submarine rather than a supratidal environment. Evidence for a submarine origin of calcium sulphate comes first from interbedded carbonates which maintain a marine fauna to the transitional contacts with overlying anhydrite. At these contacts, limestone and anhydrite are regularly interlaminated on a mm scale without disruptive or displacive nodular or enterolithic structures, which are typical of sabkhas. Intertidal sediments normally underlie the displacively grown sulphates of sabkhas, yet algal stromatolites or mats, flat pebble conglomerates or such desiccation structures as mudcracks are lacking at the dozens of limestone-anhydrite contacts examined. Extensive dolomitization is a normal consquence of lateral brine movements in sabkhas, but dolomite is a minor constituent (less than 10 per cent) in Otto Fiord limestones. The deficiency of dolomite can be explained by lack of lateral or downward movements of dolomitizing solutions after burial of carbonate by sulphate in a submarine environment. Sabkha cycles are the product of successive progradations on almost flat surfaces, and the carbonate-sulphate couplets are typically of the order of 3 or 4 m. Nowhere in the Otto Fiord are carbonate-anhydrite couplets repeated on this scale. These couplets are typically 15 to 30 m or more thick and anhydrite units of up to 60 m thick are common. Although it is possible for anhydrite units thicker than a few metres to be generated in a supratidal environment, they should be the exception rather than the rule. The primary precipitate in the submarine environment probably was gypsum, and evidence of large, elongate gypsum crystals pseudomorphed by anhydrite occur in very regularly bedded sequences within the Otto Fiord. The most common anhydrite structure, however, is nodular mosaic or chickenwire. Finally, the sulphate deposits, on a regional scale, are axially rather than marginally situated in the basin and therefore were not laid down on basinmargin shelves. A basin axis position itself, however, does not preclude the possibility of formation in a supratidal environment. End_Page 149------------------------

Subaqueous evaporites of the Carboniferous Otto Fiord Formation, Canadian Arctic Archipelago: A summary

Research Article| May 01, 1975 Subaqueous evaporites of the Carboniferous Otto Fiord Formation, Canadian Arctic Archipelago: A summary Graham R. Davies; Graham R. Davies 1Institute of Sedimentary and Petroleum Geology, Geological Survey of Canada, Calgary, Alberta, Canada Search for other works by this author on: GSW Google Scholar W. W. Nassichuk W. W. Nassichuk 1Institute of Sedimentary and Petroleum Geology, Geological Survey of Canada, Calgary, Alberta, Canada Search for other works by this author on: GSW Google Scholar Author and Article Information Graham R. Davies 1Institute of Sedimentary and Petroleum Geology, Geological Survey of Canada, Calgary, Alberta, Canada W. W. Nassichuk 1Institute of Sedimentary and Petroleum Geology, Geological Survey of Canada, Calgary, Alberta, Canada Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1975) 3 (5): 273–278. https://doi.org/10.1130/0091-7613(1975)3<273:SEOTCO>2.0.CO;2 Article history First Online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Graham R. Davies, W. W. Nassichuk; Subaqueous evaporites of the Carboniferous Otto Fiord Formation, Canadian Arctic Archipelago: A summary. Geology 1975;; 3 (5): 273–278. doi: https://doi.org/10.1130/0091-7613(1975)3<273:SEOTCO>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract The Otto Fiord Formation of Late Mississippian to Middle Pennsylvanian age is confined to the structural and depositional center of the Sverdrup Basin in the Canadian Arctic Archipelago. It is characterized by thick cycles of anhydrite, limestone, and sandstone in outcrop, and by a diapiric halite facies in the subsurface. The proposed deposi-tional model requires accumulation of carbonate sediments during transgression to a marine maximum, followed by precipitation and crystal growth of evaporites under hypersaline subaqueous conditions during regression. This interpretation thus differs from the currently popular “sabkha” model of anhydrite genesis. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

Upper Paleozoic Evaporites in Sverdrup Basin, Arctic Canada: ABSTRACT

Carboniferous and Permian evaporites and associated rocks in Arctic regions are of current interest in terms of global paleogeography and petroleum exploration. In the Canadian Arctic Archipelago, 3 upper Paleozoic evaporite formations are present in the Sverdrup basin, a regional depression overlying the Franklinian geosyncline and containing 40,000 ft (13,000 m) of lower Carboniferous to Eocene sediments. Two of these formations are: the Otto Fiord Formation (upper Carboniferous) in the axial region of the basin, and the Mt. Bayley Formation (Lower Permian), which is closer to the eastern basin margin. A third, unnamed evaporite unit of Moscovian or younger age is present along the north coast of Ellesmere Island. The Otto Fiord Formation consists of over 1,300 ft (430 m) of interbedded anhydrite (75% by thickness) and limestone (25%) at the type section, with interbedded sandstones in other sections. The formation overlies sandstones and conglomerates of the Borup Fiord Formation (Namurian?), grades laterally into carbonates of the Nansen Formation, and is overlain by carbonates or siltstones of the Hare Fiord Formation (Moscovian at base). The Otto Fiord evaporites extend for at least 400 mi (650 km) in a broad, northeast-trending belt characterized in the south by numerous large piercement structures. Namurian and Bashkirian ammonoids discovered in these diapirs now have been found at several levels in the Otto Fiord type section. Apart from a few cubic crystal casts, there are no positive indications of halite in surface exposures of the Otto Fiord Formation; breccia zones in anhydrite and limestone are not extensive. The Otto Fiord anhydrite beds vary in fabric from indistinctly bedded nodular mosaics, to fabrics apparently pseudomorphic after coarsely crystalline gypsum. Fabrics and bedding of the anhydrite, the biota of limestone interbeds, and the associated lithofacies indicate a marine subaqueous mechanism of deposition for these evaporites. End_of_Article - Last_Page 612------------

The Mosses of Northern Ellesmere Island, Arctic Canada. II. Annotated List of the Taxa

One hundred and fifty-one species and four varieties of Musci are documented from northern Ellesmere Island, Arctic Canada. My studies have added 39 species and four varieties to the northern Ellesmere moss flora. The annotations include comments on distribution and abundance, habitats, altitudinal range, and fertility of each taxon on northern Ellesmere. Where appropriate, morphological variation and taxonomy are discussed. A new variety, Splachnum vasculosum var. heterophyllum, is proposed to accommodate arctic specimens of S. vasculosum. Cyrtomnium hymenophylloides, Distichium hagenii, Fissidens arcticus, and Polytrichum hyperboreum are illustrated. New data and observations on the taxonomy of the following taxa are presented: Aulacomnium acuminatum, Brachythecium groenlandicum, B. turgidum, Fissidens arcticus, Funaria arctica, Grimmia apocarpa var. nigrescens, Splachnum vasculosum, Voitia hyperborea, and V. nivalis. The following annotated list of northern Ellesmere Island mosses is arranged in the taxonomic order of Crum, Steere, and Anderson (1965), which is also used as the nomenclatural base. I have generally followed their taxonomic concepts, but where mine differ I state the reasons. Taxa whose names are enclosed in square brackets are provisionally excluded from the northern Ellesmere moss flora. Important synonyms are cited, in parentheses, following the names of certain taxa. After the name of each taxon I have listed the localities from which it is known. The localities and their abbreviations as used in the checklist are as follows: AF, Ayles Fiord; AL, Alert; BP, Barbeau Peak; cM, Clements Markham Inlet; DB, Doidge Bay; FC, Fort Conger; GG, Gilman Glacier; GI, Garlic Island (tentative name); HL, Heintzelman Lake; JL, Jasper Lakes (tentative name); LB, Lincoln Bay; LH, Lake Hazen; OF, Otto Fiord; 1 Part of a doctoral dissertation submitted to the University of Ottawa, Canada. Financial assistance for the field studies came from the National Museum of Natural Sciences, Canada, the National Research Council of Canada (grant A730 to R. E. Beschel), and the New York Botanical Garden (National Science Foundation grant GB-1313 to W. C. Steere). The Defence Research Board of Canada provided logistic support during all three field seasons. I thank the members of Operation Tanquary, especially Dr. Royce Longton, my companion in 1967. I am greatly indebted to the bryologists who willingly identified or verified specimens for me: Dr. Howard Crum and Dr. W. C. Steere, both of whom examined many specimens, Dr. Kjeld Holmen, Dr. A. Crundwell, and Mr. Harry Williams. The curators and staffs of the following herbaria allowed me full use of their facilities and collections: National Museum of Natural Sciences (CANM), New York Botanical Garden (NY), Plant Research Institute, Ottawa (DAO), Queen's University (QK). 2 Department of Biology, University of Ottawa, Ottawa, Canada. Present address: Department of Biology, Memorial University, St. John's, Newfoundland, Canada. This content downloaded from 207.46.13.111 on Tue, 09 Aug 2016 05:20:17 UTC All use subject to http://about.jstor.org/terms 1971] BRASSARD: NORTHERN ELLESMERE ISLAND MOSSES II 283 TF, Tanquary Fiord; TI, Taconite Inlet; VH, Van Hauen Pass; wB, Wrangle Bay; wH, Ward Hunt Island; YB, Yelverton Bay. Each locality abbreviation is followed by collection numbers in italics (which are mine unless otherwise preceded by a name); an asterisk (*) indicates a specimen with sporophytes and an exclamation point (!) denotes specimens which I have examined but which were not collected by me. A name and date in parentheses, e.g., (Steere, 1959), is a published report based on specimens which I have been unable to study. A fire at Van Hauen Pass in 1967 destroyed many of my moss specimens, and a few species which I had definitely identified in the field but of which no specimens remain are cited as sight record. After the list of localities and specimens for each taxon I have added annotations about its biology and ecology on northern Ellesmere. Where appropriate I have also included comments on taxonomy, morphological variation, illustrations, or keys. The following list comprises 71 genera, 151 species, and four varieties of Musci. I expect that future investigations on northern Ellesmere will raise its known moss flora to at least 160 species, and will in addition provide more material of rare species.

APPLICATIONS OF PHOTOGRAMMETRY TO SURVEYS OF GLACIERS IN CANADA AND ALASKA

The paper emphasizes that the choice of a proper procedure is essential for efficient glacier surveying. Terrestrial versus aerial photogrammetry and the use of electronic surveying procedures versus triangulation have been tested in surveys on the Athabasca and Saskatchewan glaciers, and on glaciers in northern Ellesmere Island, southeastern Alaska, and the Yukon Territory. The Otto Fiord glacier survey in northern Ellesmere Island demonstrates that no ground control is needed for volumetric glacier studies. Accurate maps needed for other studies depend on the establishment of control. Control can most efficiently be determined by tellurometer and phototheodolite with helicopter support, as shown in Alaskan glacier surveys. For large glaciers phototopography provides a good means of extending control from tellurometer traverse stations, as demonstrated in the Mount Kennedy survey. Simple one-color maps are an economical means of preserving survey results for future glaciological evaluation.

Rapid Advance of Glacier in Northern Ellesmere Island

OTTO FIORD, on the north-west coast of Ellesmere Island, extends for about 100 km eastward and north-eastward from Nansen Sound. The tide-water glacier at its head in 81° 20′ N., 84° 40′ W. drains the ice cap between Tanquary Fiord to the south and Phillips Inlet on the north coast of the Island. This ice cap constitutes one of the most extensive, unbroken areas of land ice in the Canadian Arctic, and maintains a general elevation of 1,800 m over an area of about 2,000 km2; the Otto Fiord glacier is by far its largest outlet on the west side. The glacier flows down from the elevation of about 1,800 m to sea-level in a straight valley 35 km long and 4–6 km wide between rugged mountains and nunataks. Neither glacier nor ice cap has been visited on the ground.