| Strathcona Fiord | |
|---|---|
  Strathcona Fiord Location in Nunavut | |
| Location | Ellesmere Island, Nunavut |
| Coordinates | 78°43′N82°55′W / 78.717°N 82.917°W |
| Ocean/sea sources | Bay Fiord |
| Basin countries | Canada |
Strathcona Fiord [1] is a fiord on the west central coast of Ellesmere Island, the most northern island within the Arctic Archipelago, Nunavut, Canada.
Strathcona Fiord is a southern tributary of Bay Fiord. The landscape in the region is fragile and spectacular. The steep hills forming the sides of the valley rise about 400 m (1,300 ft) above sea level. The striking arc of a terminal moraine marks the limit of the last ice advance in the area. Taggart Lake running eastward of the moraine drains Upper and Lower Taggart lakes into the head of the fiord. The Prince of Wales Icefield lies on the eastern flank of this valley.
Although currently there is no permanent settlement in the Strathcona Fiord area, stone tent rings and other archaeological features indicate past human habitation. Eureka, about 170 km (110 mi) to the northwest, is a weather station and staging point for scientific expeditions and for other visitors to Ellesmere Island and the Qikiqtaaluk Region. Grise Fiord is an Inuit community, located about 250 km (160 mi) to the south, also on Ellesmere Island.
A parcel of land located south of the head of Strathcona Fiord is designated Inuit Owned Land. The area is sometimes visited by hunters from the nearest Inuit community, Grise Fiord.
A large portion of the Strathcona Fiord area lies within a coal license area, owned by Canadian Sovereign Coal Corporation, a subsidiary of Weststar Resources Corporation. [2] The coal property is governed by three coal exploration licenses covering an area of 37,628 ha (92,980 acres). [3] Coal deposits in the Strathcona Fiord area are ranked from lignite to sub-bituminous and have been estimated to comprise roughly 1 billion tonnes. [4]
In January 2010, when the paleontological scientific community learned of Weststar's interest in exploring this area the Society of Vertebrate Paleontology issued a press release outlining the need to preserve the fossils in the area, [5] Within four days the Nunavut Impact Review Board received over 70 letters of concern from paleontologists and the public alike.
The vicinity of Strathcona Fiord has yielded a fossil record of tremendous international scientific significance. These fossils, including plant and animal remains, have provided a unique opportunity for understanding the effect of climatic change through the past 4 or 5 million years on the Arctic environment, and on its flora and fauna.
The only Pliocene High Arctic vertebrate fossil locality known is the Beaver Pond site at Strathcona Fiord. The Beaver Pond site was first noted by John Fyles of the Geological Survey of Canada in 1961. In 1988 he found the first vertebrate remains there. In 1992 vertebrate paleontologist, Richard Harington of the Canadian Museum of Nature, began ten summers of excavations at the site.
This fossil site includes the mummified remains of fossil plants, including trees such as an extinct larch (Larix groenlandii) and other trees indicative of a boreal forest. [6] Much of the wood preserved at the site has been gnawed by beavers [7] and some of it is fire-blackened. This exceptional site also has yielded remains of pollen, insects, mollusks, fish (a percid), frogs and mammals such as an unusual rodent, a deerlet (Boreameryx), 3-toed horse, an extinct beaver (Dipoides), a rabbit ( Hypolagus ), an unusual shrew (Arctisorex polaris), a primitive black bear (Ursus abstrusus), a badger (Arctomeles), and several other carnivores. [8] [9] [10] [11] [12] [13] [14] [15]
Paleoclimatic reconstruction suggests a mean annual temperature that was 14–19 °C (25–34 °F) warmer than present day Ellesmere Island. [16] The assemblage of Pliocene plant macrofossils (wood, leaves, cones and seeds) is typical of present-day boreal forest, as it includes alder (Alnus), birch (Betula), bogbean (Menyanthes trifoliata), larch (Larix), sweet gale (Myrica gale), spruce (Picea), pine (Pinus), and lingonberry (Vaccinium vitis-idaea), as well as the southern boreal tree, the white cedar (Thuja occidentalis). [6] [17]
The first High Arctic terrestrial fossil vertebrates were discovered in 1975, in the Strathcona Fiord by a team led by Mary R. Dawson from the Carnegie Museum. These earliest finds include the fossil remains of an alligator, considered to be Allognathosuchus , and also small arboreal mammals called plagiomenids. Since then, field expeditions in Strathcona Fiord have yielded a much more complete picture of the biodiversity of the Eocene Arctic. Although, Eocene fossil vertebrates are known from other areas on Ellesmere Island (e.g., Stenkul Fiord), and Axel Heiberg Island, Strathcona Fiord has yielded the richest vertebrate fossil record.
The fossil vertebrate record of the Eocene Arctic includes giant tortoises, varanid lizards, and boid snakes. [18] Mammal fossils are extremely diverse, including the rhino-like brontotheres, the hippo-like Coryphodon , a tapir like relative (Thuliadanta), an early horse ( Hyracotherium ?), carnivores (e.g., Viverravus , Miacis ), meat-eating creodonts (e.g. Paaeonictis), a mesonychid ( Pachyaena ), a small swimming carnivore ( Pantolestid ), a leptictid and at least five rodents (including Paramys and Microparamys). [19] [20] [21] There are over 40 fossil vertebrate sites in the Strathcona Fiord region.
There are numerous Eocene plant fossil sites, including shale units that are rich with leaves as compression fossils. [22] [23] [24] Very notable are the petrified tree stumps, some of which are preserved in their original growth position. The trees show wide growth rings indicating favorable growth conditions. [25] The fossil flora indicates the presence of rich floodplain forests dominated by dawn redwood ( Metasequoia glyptostroboides ), together with ginkgo (Ginkgo adiantoides), walnut family ( Juglans and other Juglandaceae), elms ( Ulmus spp.), birch and alder (Betulaceae), and katsura ( Cercidiphyllum ). [23] [24] Analysis of nearby fossil leaf sites from central Ellesmere Island of the same age indicate that these forests grew under very high rainfall, and can be considered to have represented a polar rainforest. [26]
This lush Eocene ecosystem thrived under a polar light regime. Like today, the region would have seen 24-hour sun in the summer and 24-hour darkness in the winter as it was positioned at almost the same latitude in the Eocene as it is today. Despite an early Eocene climate with generally mild frost-free temperatures, the polar light regime likely forced these plants to be deciduous. [23]
Ellesmere Island is Canada's northernmost and third largest island, and the tenth largest in the world. It comprises an area of 196,236 km2 (75,767 sq mi), slightly smaller than Great Britain, and the total length of the island is 830 km (520 mi).
Axel Heiberg Island is an uninhabited island in the Qikiqtaaluk Region, Nunavut, Canada. Located in the Arctic Ocean, it is the 32nd largest island in the world and Canada's seventh largest island. According to Statistics Canada, it has an area of 43,178 km2 (16,671 sq mi). It is named after Axel Heiberg.
Driftwood Canyon Provincial Park is a provincial park in British Columbia, Canada. Driftwood Canyon Provincial Park covers 23 ha of the Bulkley River Valley, on the east side of Driftwood Creek, a tributary of the Bulkley River, 10 km northeast of the town of Smithers. The park is accessible from Driftwood Road from Provincial Highway 16. It was created in 1967 by the donation of the land by the late Gordon Harvey (1913–1976) to protect fossil beds on the east side of Driftwood Creek. The beds were discovered around the beginning of the 20th century. The park lands are part of the asserted traditional territory of the Wet'suwet'en First Nation.
Mary R. Dawson was a vertebrate paleontologist and curator emeritus at the Carnegie Museum of Natural History in Pittsburgh, Pennsylvania.
Natalia Rybczynski is a Canadian paleobiologist, professor and researcher.
Chamaecyparis eureka is an extinct species of conifer in the family Cupressaceae. It is known from fossil foliage found in the Buchanan Lake Formation deposits, dated to the middle Eocene Lutetian stage, from western Axel Heiberg Island, located in the Arctic Ocean in the Qikiqtaaluk Region, Nunavut, Canada. C. eureka is the oldest confirmed member of the genus Chamaecyparis, which includes five to six living species, depending on circumscription, which are native to Eastern Asia, Japan, and North America.
Charles Richard Harington was a Canadian zoologist born in Calgary in May 1933.
The Princeton Chert is a fossil locality in British Columbia, Canada, which comprises an anatomically preserved flora of Eocene Epoch age, with rich species abundance and diversity. It is located in exposures of the Allenby Formation on the east bank of the Similkameen River, 8.5 km (5.3 mi) south of the town of Princeton, British Columbia.
The McAbee Fossil Beds is a Heritage Site that protects an Eocene Epoch fossil locality east of Cache Creek, British Columbia, Canada, just north of and visible from Provincial Highway 97 / the Trans-Canada Highway. The McAbee Fossil Beds, comprising 548.23 hectares, were officially designated a Provincial Heritage Site under British Columbia's Heritage Conservation Act on July 19, 2012. The site is part of an old lake bed which was deposited about 52 million years ago and is internationally recognised for the diversity of plant, insect, and fish fossils found there. Similar fossil beds in Eocene lake sediments, also known for their well preserved plant, insect and fish fossils, are found at Driftwood Canyon Provincial Park near Smithers in northern British Columbia, on the Horsefly River near Quesnel in central British Columbia, and at Republic in Washington, United States. The Princeton Chert fossil beds in southern British Columbia are also Eocene, but primarily preserve an aquatic plant community. A 2016 review of the early Eocene fossil sites from the interior of British Columbia discusses the history of paleobotanical research at McAbee, the Princeton Chert, Driftwood Canyon, and related Eocene fossil sites such as at Republic.
The Allenby formation is a sedimentary rock formation in British Columbia which was deposited during the Ypresian stage of the Early Eocene. It consists of conglomerates, sandstones with interbedded shales and coal. The shales contain an abundance of insect, fish and plant fossils known from 1877 and onward, while the Princeton Chert was first indented in the 1950's and is known from anatomically preserved plants.
The Eureka Sound Formation is a geologic formation found in the Canadian Territory of Nunavut on Ellesmere Island, which is part of the Canadian Arctic Archipelago. The Eureka Sound Formation is Tertiary in age.
The Margaret Formation is a geologic formation of the Eureka Sound Group in the Sverdrup Basin in Northwest Territories and Nunavut, Canada. The unit belonging to the Eureka Sound Group which crops out at Ellesmere Island preserves fossils dating back to the Early Eocene period, or Wasatchian in the NALMA classification.
The Coldwater Beds are a geologic formation of the Okanagan Highlands in British Columbia, Canada. They preserve fossils dating back to the Ypresian stage of the Eocene period, or Wasatchian in the NALMA classification.
Ulmus okanaganensis is an extinct species of flowering plant in the family Ulmaceae related to the modern elms. The species is known from fossil leaves, flowers, and fruits found in the early Eocene deposits of northern Washington state, United States and similar aged formations in British Columbia, Canada.
Ignacius is a genus of extinct mammal from the early Cenozoic era. This genus is present in the fossil record from around 62-33 Ma. The earliest known specimens of Ignacius come from the Torrejonian of the Fort Union Formation, Wyoming and the most recent known specimens from Ellesmere Island in northern Canada. Ignacius is one of ten genera within the family Paromomyidae, the longest living family of any plesiadapiforms, persisting for around 30 Ma during the Paleocene and Eocene epochs. The analyses of postcranial fossils by paleontologists suggest that members of the family Paromomyidae, including the genus Ignacius, most likely possessed adaptations for arboreality.
Comptonia columbiana is an extinct species of sweet fern in the flowering plant family Myricaceae. The species is known from fossil leaves found in the early Eocene deposits of central to southern British Columbia, Canada, plus northern Washington state, United States, and, tentatively, the late Eocene of Southern Idaho and Earliest Oligocene of Oregon, United States.
Equisetum similkamense is an extinct horsetail species in the family Equisetaceae described from a group of whole plant fossils including rhizomes, stems, and leaves. The species is known from Ypresian sediments exposed in British Columbia, Canada. It is one of several extinct species placed in the living genus Equisetum.
The paleoflora of the Eocene Okanagan Highlands includes all plant and fungi fossils preserved in the Eocene Okanagan Highlands Lagerstätten. The highlands are a series of Early Eocene geological formations which span an 1,000 km (620 mi) transect of British Columbia, Canada and Washington state, United States and are known for the diverse and detailed plant fossils which represent an upland temperate ecosystem immediately after the Paleocene-Eocene thermal maximum, and before the increased cooling of the middle and late Eocene to Oligocene. The fossiliferous deposits of the region were noted as early as 1873, with small amounts of systematic work happening in the 1880-90s on British Columbian sites, and 1920-30s for Washington sites. A returned focus and more detailed descriptive work on the Okanagan Highlands sites revived in the 1970's. The noted richness of agricultural plant families in Republic and Princeton floras resulted in the term "Eocene orchards" being used for the paleofloras.
The Eocene Okanagan Highlands or Eocene Okanogan Highlands are a series of Early Eocene geological formations which span a 1,000 km (620 mi) transect of British Columbia, Canada, and Washington state, United States. Known for a highly diverse and detailed plant and animal paleobiota the paleolake beds as a whole are considered one of the great Canadian Lagerstätten. The paleobiota represented are of an upland subtropical to temperate ecosystem series immediately after the Paleocene–Eocene thermal maximum, and before the increased cooling of the middle and late Eocene to Oligocene. The fossiliferous deposits of the region were noted as early as 1873, with small amounts of systematic work happening in the 1870–1920s on British Columbian sites, and 1920–1930s for Washington sites. Focus and more detailed descriptive work on the Okanagan Highland sites started in the late 1960s.
The paleofauna of the Eocene Okanagan Highlands consists of Early Eocene arthropods, vertebrates, plus rare nematodes and molluscs found in geological formations of the northwestern North American Eocene Okanagan Highlands. The highlands lake bed series' as a whole are considered one of the great Canadian Lagerstätten. The paleofauna represents that of a late Ypresian upland temperate ecosystem immediately after the Paleocene-Eocene thermal maximum, and before the increased cooling of the middle and late Eocene to Oligocene. The fossiliferous deposits of the region were noted as early as 1873, with small amounts of systematic work happening in the 1880-90s on British Columbian sites, and 1920-30s for Washington sites. Focus and more detailed descriptive work on the Okanagan Highlands site started in the last 1970's. Most of the highlands sites are preserved as compression-impression fossils in "shales", but also includes a rare permineralized biota and an amber biota.
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