Omar | |
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![]() An Omar with a hemispherical void in its side. | |
General | |
Category | Native Minerals |
Omars, are a distinctive type of glacial erratic that consists of dark siliceous greywacke and exhibits prominent rounded, often deep, hemispherical voids and pits. The hemispherical voids and pits result from the selective dissolution of carbonate concretions within the greywacke. The greywacke is identifiable by its low metamorphic grade and the 10–40% rock fragments, distinctive volcanic clasts, and spherical carbonate concretions that it contains. Omars are typically rounded and range in size from pebbles to boulders. Their rounded shape, whether found in glacial tills or glacial-fluvial (outwash) gravels, indicate that they were eroded from pre-existing littoral or fluvial deposits. Omars are typically found associated with granules and pebbles of oolitic jasper that were transported from the Belcher Islands in Hudson Bay, Canada. [1] [2] [3]
The name given these glacial erratics refer to their source, which is the Proterozoic Omarolluk Formation in the Belcher Islands in southeast Hudson Bay. The Laurentide Ice Sheet eroded omars from the Belcher Islands, an archipelago limited to only about a quarter of 1% of Hudson Bay. Glaciers moved omars from the southeastern part of Hudson Bay to central Canada and into the U.S. where they were deposited on moraines. Because scientists know precisely where they came from they are very valuable in documenting the movement of glaciers. [2] [4] [5]
There is uncertainty on how to translate the proper name Omarolluk (and omar rocks). According to the records of the Canada Centre for Mapping and Earth Observation Natural Resources, the features Omarolluk Sound and Omarolluk Formation were named after Omarolluk, an Inuit man who accompanied and guided R. J. Flaherty on numerous geological surveys of the Belcher Islands and elsewhere in the Canadian north. He was probably an Inuktitut-dialect speaker from the eastern coast of Hudson Bay. The spelling likely varied from the originally pronounced but unrecorded aural form of the name. Despite the expected natural-feature designations, Omarolluk was surely an actual person. There are three possible translations, as follows: (1) Best: In the subdialect (Itivimiut) of the Nunavik dialect of Inuktitut, the phoneme /j/ was and still is up to a point pronounced more or less like English r and generally transcribed as such, and so the name in the standard Canadian Inuit spelling might have been *Uumajurluk (pronounced /uumaruRluk/: r = English r; R = French r), that is, ‘bad animal’ (uumajuq ‘animal’; luk ‘bad’) as a guess. [6] (2) Somewhat similar but possibly: ‘poor reason for being alive’, uumaq-jjut-luk ‘be.alive–reason.for/cause.for–bad/poor’ (-jjut takes the form -rut after the uvular [q] and then deletes it, at least in the contemporary language). The initial o is dubious for an expected u. [7] (3) A distant Yup’ik possibility if applied to a rock stratum: Umaq is a seam between the upper and lower parts of a kamik (sealskin boot); the ruq part would mean ‘to become’, and luk is the ‘it’, thus imperfectly ‘it becomes a seam’, but if umaaq, then it becomes ‘rip (at the seam)’, a verb, which would mean something like ‘it has a habit of ripping at the seam’. [8] [9]
Hudson Bay, sometimes called Hudson's Bay, is a large body of saltwater in northeastern Canada with a surface area of 1,230,000 km2 (470,000 sq mi). It is located north of Ontario, west of Quebec, northeast of Manitoba, and southeast of Nunavut, but politically entirely part of Nunavut. It is an inland marginal sea of the Arctic Ocean. The Hudson Strait provides a connection between the Labrador Sea and the Atlantic Ocean in the northeast, while the Foxe Channel connects the Hudson Bay with the Arctic Ocean in the north. It drains a very large area, about 3,861,400 km2 (1,490,900 sq mi), that includes parts of southeastern Nunavut, Alberta, Saskatchewan, Ontario, Quebec, all of Manitoba, and parts of the U.S. states of North Dakota, South Dakota, Minnesota, and Montana. Hudson Bay's southern arm is called James Bay.
The Belcher Islands are an archipelago in the southeast part of Hudson Bay near the centre of the Nastapoka arc. The Belcher Islands are spread out over almost 3,000 km2 (1,200 sq mi). Administratively, they belong to the Qikiqtaaluk Region of Nunavut, Canada. The hamlet of Sanikiluaq is on the north coast of Flaherty Island and is the southernmost in Nunavut. Along with Flaherty Island, the other large islands are Kugong Island, Tukarak Island, and Innetalling Island. Other main islands in the 1,500–island archipelago are Moore Island, Wiegand Island, Split Island, Snape Island and Mavor Island, while island groups include the Sleeper Islands, King George Islands, and Bakers Dozen Islands.
Inuktitut syllabics is an abugida-type writing system used in Canada by the Inuktitut-speaking Inuit of the territory of Nunavut and the Nunavik and Nunatsiavut regions of Quebec and Labrador, respectively. In 1976, the Language Commission of the Inuit Cultural Institute made it the co-official script for the Inuit languages, along with the Latin script.
The Qikiqtaaluk Region, Qikiqtani Region or the Baffin Region is the easternmost, northernmost, and southernmost administrative region of Nunavut, Canada. Qikiqtaaluk is the traditional Inuktitut name for Baffin Island. Although the Qikiqtaaluk Region is the most commonly used name in official contexts, several notable public organizations, including Statistics Canada prior to the 2021 Canadian census, use the older term Baffin Region.
Somerset Island is a large, uninhabited island of the Arctic Archipelago, that is part of the Canadian territory of Nunavut. The island is separated from Cornwallis Island and Devon Island to the north by the Parry Channel, from Baffin Island to the east by Prince Regent Inlet, from the Boothia Peninsula to the south by Bellot Strait, and from Prince of Wales Island to the west by Peel Sound. It has an area of 24,786 km2 (9,570 sq mi), making it the 46th largest island in the world and Canada's twelfth largest island.
The Ungava Peninsula, officially Péninsule d'Ungava, is the far northwestern part of the Labrador Peninsula of the province of Quebec, Canada. Bounded by Hudson Bay to the west, Hudson Strait to the north, and Ungava Bay to the east, it covers about 252,000 km2 (97,000 sq mi). Its northernmost point is Cape Wolstenholme, which is also the northernmost point of Quebec. The peninsula is also part of the Canadian Shield, and consists entirely of treeless tundra dissected by large numbers of rivers and glacial lakes, flowing generally east–west in a parallel fashion. The peninsula was not deglaciated until 6,500 years ago and is believed to have been the prehistoric centre from which the vast Laurentide Ice Sheet spread over most of North America during the last glacial epoch.
Southampton Island is a large island at the entrance to Hudson Bay at Foxe Basin. One of the larger members of the Arctic Archipelago, Southampton Island is part of the Kivalliq Region in Nunavut, Canada. The area of the island is stated as 41,214 km2 (15,913 sq mi) by Statistics Canada. It is the 34th largest island in the world and Canada's ninth largest island. The only settlement on Southampton Island is Coral Harbour, called Salliq in Inuktitut.
Coats Island lies at the northern end of Hudson Bay in the Kivalliq Region of Nunavut. At 5,498 km2 (2,123 sq mi) in size, it is the 107th largest island in the world, and Canada's 24th largest island.
The Laurentide ice sheet was a massive sheet of ice that covered millions of square miles, including most of Canada and a large portion of the Northern United States, multiple times during the Quaternary glacial epochs, from 2.58 million years ago to the present.
The Cordilleran ice sheet was a major ice sheet that periodically covered large parts of North America during glacial periods over the last ~2.6 million years.
Tukarak Island is an uninhabited island in Qikiqtaaluk Region, Nunavut, Canada. Located in Hudson Bay, it is a member of the Belcher Islands group. Along with Flaherty Island, Innetalling Island, and Kugong Island, it is one of the four large islands in the group.
Innetalling Island is an uninhabited island in Qikiqtaaluk Region, Nunavut, Canada. Located in Hudson Bay's Omarolluk Sound, it is a member of the Belcher Islands group. It runs from Fairweather Sound at its northern end to Ridge Passage at its southern one. Fairweather Harbour is located on the north end of the island's east side.
The Ottawa Islands are a group of currently uninhabited islands situated in the eastern edge of Canada's Hudson Bay. The group comprises 24 small islands, located at approximately 60N 80W. The main islands include Booth Island, Bronson Island, Eddy Island, Gilmour Island, J. Gordon Island, Pattee Island, and Perley Island. The highest point is on Gilmour Island, which rises to over 1,800 ft (550 m). Located a short distance off the northwest coast of Quebec's Ungava Peninsula, they, like the other coastal islands in Hudson Bay, were historically part of the Northwest Territories, and became Crown Land upon the creation of Nunavut in 1999. Nunavik Inuit have occupied these islands since time immemorial and gained constitutionally-protected harvest and access rights under the Nunavik Inuit Land Claim Agreement signed in 2007.
Lake Bassano was a proglacial lake that formed in the Late Pleistocene during the deglaciation of south-central Alberta by the impoundment of a re-established drainage system and addition of glacial meltwater. It is associated with the development of through-flowing drainage within the Red Deer River basin in particular, and the South Saskatchewan drainage network in general. Approximately 7,500 square kilometres (2,900 sq mi) of the Bassano basin is covered with lacustrine sediments. These sediments are bordered by the topographically higher Buffalo Lake Moraine to the west, the Suffield Moraine to the east and the Lethbridge Moraine to the south.
Griffith Island lies within the Arctic Archipelago in the Qikiqtaaluk Region of northern Canada's territory of Nunavut. It is one of the mid-channel islands in the western sector of Barrow Strait.
New England is a region in the North Eastern United States consisting of the states Rhode Island, Connecticut, Massachusetts, New Hampshire, Vermont, and Maine. Most of New England consists geologically of volcanic island arcs that accreted onto the eastern edge of the Laurentian Craton in prehistoric times. Much of the bedrock found in New England is heavily metamorphosed due to the numerous mountain building events that occurred in the region. These events culminated in the formation of Pangaea; the coastline as it exists today was created by rifting during the Jurassic and Cretaceous periods. The most recent rock layers are glacial conglomerates.
The Missinaibi Formation is a Late Pleistocene geologic formation in the Hudson Bay Lowlands in Northern Ontario, Canada. The formation lies within Missinaibi Provincial Park.
The Keewatin ice sheet was a major ice sheet that periodically covered large parts of North America during glacial periods over the last ~2.6 million years. This included the following areas:
The Baffin ice sheet was the most northerly portion of the Laurentide Ice Sheet, centered in the Foxe Basin between Baffin Island and the Melville Peninsula north of Hudson Bay. Blocked from a southward flow by the Keewatin and Labrador Ice sheets, it moved north and eastward across Baffin Island into the Baffin Sound. Two smaller ice domes formed along the island chain of the Sound as the Barnes Dome, Penny Dome and the Amadjuak Dome.
The Labrador ice sheet was a major ice sheet that periodically covered large parts of North America during glacial periods over the last ~2.6 million years. The seam between the two ice sheets passed over the northern tip of the Ungava Peninsula passing south across Hudson Bay and on to the Ontario shore near Fort Stevens. This seam continued southward across Lake Superior, east of the Keweenaw Peninsula of Michigan. Southward into Wisconsin, along the Lake Michigan shoreline, crossing into western Illinois. Reaching down the Mississippi River valley to its junction with the Missouri River, it reaches its most southern point. At this point, the ice sheet no longer abuts the Keewatin ice sheet.
Prest, V.K. (1990) Laurentide ice-flow patterns: A historical review, and implications of the dispersal of Belcher Island erratics. Géographie Physique et Quaternaire 44(2):113-136.