Horton River Research Articles

Progress in the taxonomy of Late Cretaceous high-latitude radiolarians: insights from the Horton River area, Northwest Territories, Canada

Abstract. Radiolarians have proven to be exceptional tools in biostratigraphic and paleoenvironmental studies despite their relatively low preservation potential in the sedimentary record. Reports of Upper Cretaceous radiolarians in high northern latitudes are scant, and their taxonomy is not often discussed in the few reports available in the literature. In this study, we describe one new genus and three new species of polycystine radiolarians from Upper Cretaceous strata of the northern mainland coast of Arctic Canada. The specimens were recovered from the Santonian–middle Campanian Smoking Hills Formation and the middle Campanian–Maastrichtian Mason River Formation and are assigned to the genus Canadasphaera n. gen. (Order Spumellaria) and the species Canadasphaera inuita n. sp., Kuppelella rusti n. sp., and Lithocampe? rara n. sp. The taxonomic notes provided in this study improve our understanding of Late Cretaceous radiolarians from high northern latitudes and serve as a foundation for future Cretaceous radiolarian research in Arctic regions. Canadasphaera: urn:lsid:zoobank.org:act:C6B7B702-4B74-472D-8893-0A41B93A5066, date of registration: 19 April 2024 Canadasphaera inuita: urn:lsid:zoobank.org:act:C30E555B-EE94-4680-87D1-5CE83E128461, date of registration: 19 April 2024 Kuppelella rusti: urn:lsid:zoobank.org:act:68ECB628-2E74-4748-ACA4-DD1A33B05837, date of registration: 19 April 2024 Lithocampe? rara: urn:lsid:zoobank.org:act:25E569B2-93A8-425F-BB7C-D29A0437763F, date of registration: 19 April 2024

Glacial landforms and sediments (landsystem) of the Smoking Hills area, Northwest Territories, Canada: Implications for regional Pliocene – Pleistocene Laurentide Ice Sheet dynamics

The Smoking Hills area in the western Canadian Arctic was purported to contain a regionally rare Quaternary stratigraphic section with multiple, local ice cap-derived tills and a long chronology constrained by palaeomagnetic markers. We present a fundamental revision of previous glacial and magnetostratigraphic interpretations based on detailed sedimentological and structural analyses of the main stratigraphic section and many new exposures, cosmogenic nuclide isochron burial dating, and a systematic reconstruction of the geomorphology and landscape evolution using a glacial landsystem approach. We demonstrate that the Smoking Hills area was fully glaciated during the last (Wisconsinan) glaciation. Previously reported tills ascribed to multiple glaciations represent instead a complex facies sequence of glacitectonic thrust stacking of Laurentide Ice Sheet (LIS) sourced diamictons, glacilacustrine and glacifluvial deposits, together with previously unidentified, poorly-consolidated Cretaceous bedrock rafts and deformed intraclasts. Much of this sedimentation and glacitectonic activity dates to the last (Wisconsinan) glaciation and can be reconciled with a polythermal ice sheet marginal landsystem signature, wherein ice-cored moraine belts are developed over subglacial bedforms (flutings) arranged in discrete flowsets. The flowsets record the complex interaction of ice streams nourished by ice flowing from three main sources: Great Bear Lake to the south, Amundsen Gulf (Franklin Bay) to the east and Liverpool Bay (Mackenzie Valley) to the southwest. Decoupling of the ice margins of these three ice sources gave rise to interlobate ice-dammed lake development over the lower Horton River area during final deglaciation. A cosmogenic 26Al/10Be isochron burial age of 2.9 ± 0.3 Ma (1σ, n = 4) from the lowermost glacial diamicton and glacitectonite sequence provides evidence of perhaps the earliest continental glaciation of this region. This deposit postdates, or is perhaps a later re-advance of the same initial glaciation that produced widespread glacitectonic disturbance of bedrock in preglacial valley networks and early glacifluvial and glacilacustrine deposits containing an ice wedge pseudomorph. Subsequent glaciations have largely removed or cannibalised pre-existing records to construct complex till and glacitectonite stacks that contain reworked organics with non-finite radiocarbon ages. One site preserves buried “old” glacier ice in which prominent ice wedges had formed during an interglacial permafrost phase and were then deformed down-flow by the LIS during the Wisconsinan glaciation.

A rare double skeleton of the silicoflagellate <i>Corbisema</i>

Silicoflagellates are usually associated with simple skeletons made of a domal latticework of rod-shaped elements, known as the apical structure, which is attached to a polygonal basal ring. Silicoflagellate reproduction is poorly understood (Moestrup & Thomsen, 1990) but they are known to divide mitotically associated with the construction of a double skeleton. Such double skeletons connected at the abapical face of the basal ring are observed from Recent and fossil material. Double skeletons of Dictyocha and Distephanus noted in Cenozoic sediments (Dumitricǎ, 1973, pl. 4, fig. 8; Boney, 1976) show basal rings positioned with their corners in close proximity. Ling & Takahashi (1985, pl. 1, fig. 5) and Takahashi et al . (2009, pl. 2, figs 3, 5) illustrate Distephanus with the spines of the two skeletons in exact alignment with one another. Recent work in a Campanian sequence of strata near Horton River, District of Mackenzie in the Northwest Territories, Canada …

Unusual assemblages of Late Cretaceous silicoflagellates from the Canadian Archipelago

Devon and Ellef Ringnes islands in the Canadian Arctic Archipelago contain well-preserved Santonian through early Campanian silicoflagellates. These occur in three unusual assemblages, which comprise three biostratigraphic zones. The oldest, the Vallacerta tumidula Partial Range Zone of Santonian age, contains an extremely variable microflora that includes species of the poorly-known genus Variramus, two new species of Cornua, and a new genus Umpiocha. The Schulzyocha ruppelii Range Zone of early Campanian age includes several species of the new genus Schulzyocha, reflecting quadrate silicoflagellate skeletal morphologies that lack a basal structure. The youngest assemblage includes the poorly-known species Cornua trifurcata, the nominative taxon of the C. trifurcata Partial Range Zone (proposed by McCartney et al., in press c; emended herein), which allows a correlation with a silicoflagellate-bearing sequence from the Horton River area, Northwest Territories of Canada. This report presents information on 24 silicoflagellate taxa, proposes 2 new genera, Schulzyocha and Umpiocha, and describes 13 new species and 1 new combination. All of these new taxa disappear by the top of the Campanian Cornua trifurcata Partial Range Zone. These assemblages reveal a new history of silicoflagellate evolution prior to the late Campanian, the period from which most of our prior knowledge about Cretaceous silicoflagellates was derived. The assemblages show progressive change from skeletons with highly variable morphologies to more stable silicoflagellate skeletal geometry. Two important Corbisema species, C. apiculata and C. archangelskiana, appear to be derived from separate lines within Cornua in the latest Santonian and early Campanian. The important Cretaceous genus Lyramula makes its first appearance at the beginning of the Campanian.

Upper Cretaceous diatom biostratigraphy of the Arctic archipelago and northern continental margin, Canada

Strata in the Canadian Arctic contain diverse and moderately well-preserved Late Cretaceous siliceous microfossil as- semblages. One-hundred-twelve samples were analyzed from a composite stratigraphic section (1094m-thick) of the Smoking Hills, Mason River and Kanguk formations. Four sections were examined: (1) Slidre Fjord on Ellesmere Island; (2) Hoodoo Dome on Ellef Ringnes Island; (3) Cape Nares on Eglinton Island; and (4) Horton River on the Anderson Plains, Northwest Territories. Two hun- dred-three diatom taxa were identified in forty-nine productive samples. Four Upper Cretaceous diatom zones are proposed for the Ca- nadian Arctic based on the biostratigraphic distribution of diatoms: (i) the Upper Cenomanian to Upper Santonian(?) Gladius antiquus Concurrent Range Zone, (ii) the Lower Campanian Costopyxis antiqua Partial Range Zone, (iii) the lower Upper Campanian Trinacria indefinita Interval Zone, and (iv) the upper Upper Campanian Stephanopyxis simonseni Partial Range Zone. The diatom assemblages are similar to those of Alpha Ridge (Arctic Ocean), Ural Mountains (Russia), and Campbell Plateau (SW Pacific Ocean), enabling diatom-based biostratigraphical correlations within the northern high-latitudes and to the southern high-latitudes. A fifth biostratigraphic zone, Azpeitiopsis morenoensis Concurrent Range Zone, is also proposed, based on common and widespread distribution of the nominative taxon in lower to upper Maastrichtian sediments. Sufficient data is now available to establish the construction of a diatom-based standard zonal framework for the Upper Cretaceous. Two new combinations, Trochosira denticulatum (Strelnikova) Tapia and Trochosiropsis polychaeta (Strelnikova) Tapia are here proposed.

Cold-climate shattering (1974 to 1993) of 200 glacial erratics on the exposed bottom of a recently drained arctic lake, Western Arctic coast, Canada

The shattering of 200 glacial erratics on the exposed bottom of an Arctic lake that drained rapidly, probably in 1955, was studied from 1974 to 1993. Most of the erratics were igneous rocks derived from the Canadian Shield. The erratics, which were unshattered before 1974, had already survived, in varying degrees, at least three prior stages of shattering: first, when many of the rocks were in the thin active layer of the glacial till that covered the area; second, when all of the rocks, after submergence by lake enlargement, underwent annual freeze–thaw cycles under saturated conditions; and third when, after rapid lake drainage, the rocks were exposed to cold sub-aerial climate conditions before being marked for study in 1974. The 200 rocks were checked in 1977, 1978, 1979, 1987, 1988 and 1993. In 1993, the last year of observation, 180 of the original 200 rocks were relocated. The results showed that at least 10 of the 200 rocks had shattered, these being: at least 2 out of about 136 granites; 1 out of about 6 gneisses; 1 out of 2 sandstones; and 6 out of about 22 dolomites. The impervious granites probably hydrofractured from the freezing of water in closed to semi-closed systems or from thermal shocks. Rocks which facilitated the entry of water, such as those with a foliation, schistosity or porosity, broke the most frequently, many probably from ice segregation. Some of the dolomites probably shattered explosively. In support of the ice segregation theory of shattering for some types of rocks, an example is given of present-day ice segregation in a Cretaceous shale at the mouth of nearby Horton River, NWT. Copyright © 1999 John Wiley & Sons, Ltd.

Grizzly Bear, Ursus arctos, predation on Muskox, Ovibos moschatus, calves near the Horton River, Northwest Territories

Grizzly Bear, Ursus arctos, predation on Muskox, Ovibos moschatus, calves near the Horton River, Northwest Territories

Prehistoric Clinker Use on the Cape Bathurst Peninsula, Northwest Territories, Canada: The Dynamics of Formation and Procurement

Fieldwork conducted on the Cape Bathurst Peninsula, Northwest Territories, Canada, has resulted in the discovery of 75 sites representing occupations spanning more than 3,000 years. Nearly all of the sites are characterized by the predominant use of a distinctive rock called a “clinker.” Resembling a basalt-to-obsidian-like material, it is formed by the spontaneous combustion of local organic-rich shales. The fusing occurs in burning areas called bocannes that are common along the Horton River and the cliffs along the eastern shore of the peninsula. Despite the evidence for intensive use on Cape Bathurst and the more general Mackenzie Delta region, none of the four potential quarry sources yielded evidence of actual prehistoric use. This is attributed to the dynamic nature of the formation and erosion of the bocannes over the last several thousand years.

The Horton River Breakthrough and Resulting Geomorphic Changes in a Permafrost Environment, Western Arctic Coast, Canada

Dendrochronological analysis and radiocarbon dating show that a breakthrough to the sea occurred along the lower course of the Horton River after 1640 AD. At the breakthrough site, the Horton River flowed 10 m above sea level so that river erosion and delta building would have been rapid. By 1826, when the coast was mapped by the expedition of Dr. John Richardson, the Horton Delta had a surface area of about 10 to 15 km2, approximately one third of the present area. Construction of the delta has protected the adjacent sea cliffs from wave erosion. Attention is paid to the nature of geomorphic change in a permafrost environment and the role of river and sea ice in affecting changes.

Pleistocene geology and geomorphology of the Smoking Hills Upland and lower Horton River Arctic coast of mainland Canada

The Smoking Hills Upland and lower Horton River valley, on the Arctic coast of Canada 300 km east of the Mackenzie Delta, retain an extended record of subaerial erosion of nearly flat-lying Cretaceous shales. This erosion led to the development of (i) a very gently sloping low-relief upland surface (Early Pleistocene(?)), (ii) a slightly steeper intermediate surface, and (iii) younger steep valley walls, terraces, and broad valley bottoms. No direct glacial contribution to any of these landforms can be recognized. An early interglacial(?) fluvial episode is recorded in plateau-cap sediments. Suggestions of an early (mid-Pleistocene or earlier) glaciation overwhelming the Smoking Hills Upland are found in (i) anomalies in drainage patterns, (ii) disturbances in bedding, believed to have been caused by ice thrusting, and (iii) local occurrences of diamictons. Later, probably Early Wisconsinan, glaciation left meltwater channels in peripheral areas. The Late Wisconsinan ice sheet did not reach the Smoking Hills Upland but may have had an indirect influence by modyfying discharge and sediment transport of Horton River.

Patterns of Community Structure and Morphology of Bryophytes and Lichens Relative to Edaphic Gradients in the Subarctic Forest-Tundra of Northwestern Canada

Patterns of Community Structure and Morphology of Bryophytes and Lichens Relative to Edaphic Gradients in the Subarctic Forest-Tundra of Northwestern Canada

The Horton River Breakthrough and Resulting Geomorphic Changes in a Permafrost Environment, Western Arctic Coast, Canada

The Horton River Breakthrough and Resulting Geomorphic Changes in a Permafrost Environment, Western Arctic Coast, Canada

W. W. Brideaux & D. J. McIntyre 1975. Miospores and Microplankton from Aptian–Albian rocks along Horton River, District of Mackenzie. Geological Survey of Canada Bulletin 252. 85 pp., 7 figs, 14 pls. Ottawa. Price $5.00 (Canada); $6.00 (other countries).

W. W. Brideaux & D. J. McIntyre 1975. Miospores and Microplankton from Aptian–Albian rocks along Horton River, District of Mackenzie. Geological Survey of Canada Bulletin 252. 85 pp., 7 figs, 14 pls. Ottawa. Price $5.00 (Canada); $6.00 (other countries).

Morphologic changes indeflandreafrom a campanian section, district of Mackenzie, N.W.T., Canada

Abstract Diverse microfloras from a section of Santonian to Maastrichtian age from the Horton River, N.W.T., contain abundant specimens of species of Deflandrea and other peridinioid forms. The abundance and ranges of these species, particularly in the Campanian, permit establishment of three microfloral divisions. Six new species of Deflandrea are described: D. ditissima, D. decorosa, D. coronata, D. microarma, D. amphiata, D. biapertura. A new genus, Laciniadinium, has been established, with two new species, L. orbiculatum, and L. biconiculum. In the lower part of the section, morphologic changes in three new Deflandrea species suggest that they form a lineage of cyst species. It may be that the lineage has arisen in response to change in environmental conditions.

The Northern Limits of Moose (Alces alces) in Western Canada

Published and unpublished distributional records are presented for moose ( Alces alces ) near treeline and on the tundra between Hudson Bay and the Alaska-Yukon boundary. Moose appear to occur regularly on much of the northwestern tundra between Horton River and Alaska, and locally in the Coppermine area—probably in response to the food supply provided by extensive willow thickets. They have been seen irregularly in many other places on the tundra. There has been an increase in the number of observations of moose in recent years. This increase may reflect either an upward response by moose populations to succession following fire in coniferous forests near treeline, or increased human mobility and travel (or both), rather than a long term northward expansion of the moose population.

Application of stream order numbers to the Merrimack River Basin

This study shows that the Merrimack River basin is a Horton river basin. An amendment to the Scheidegger ordering system is proposed, based on the length of stream source segments. These amended orders can be used to identify incorrectly mapped sources and to identify which junctions in a single Scheidegger order have longer than average sources upstream.

Post-Glacial Drainage Changes in the Darnley Bay Area, N. W. T., Canada

POST-GLACIAL DRAINAGE CHANGES IN THE DARNLEY BAY AREA, N. W. T. , CANADA* J. Ross Mackay University of British Columbia Darnley Bay is north of Great Bear Lake and midway between the Mackenzie and Coppermine Rivers which flow north into the Arctic Ocean. The three rivers which drain the area, namely the Brock, Hornaday , and Horton Rivers, are inaccurately shown on the latest 8 mile topographic sheet which was published in 1945, but a new and accurate map prepared from aerial photographs will shortly be available. Darnley Bay was discovered by Dr. John Richardson in 1826 but part of the inland area is still largely unknown. The mouth of the Horton River was discovered by Richardson and the river itself explored by Vilhjalmur Stefansson and Rudolph Anderson in 1909-12. ^ A, J. Stone, an American naturalist collecting for the American Museum of Natural History, discovered the Hornaday River in 1898. Until recent years the large size of the Hornaday River was unsuspected and it was considered to be a small stream rising from a lake 10 miles south of Darnley Bay, when in reality the river is about 200 miles long and the lake does not exist. The southern party of the 1913-18 Canadian Arctic Expedition explored the Brock River for 23 miles from its mouth. ^ Air photographs show it to be some 80 miles in length. The purpose of this paper is to discuss some of the post-glacial drainage changes which have occurred in the drainage basins of the Brock, Hornaday and Horton Rivers in the Darnley Bay area. Field work was done in the summer of 1951 and liberal use has been made of photo interpretation in extending the study to include a larger area. General Description The Darnley Bay region is in the barren grounds or tundra beyond the tree limit which lies close to the Horton River. Permanently frozen ground or permafrost is usually within five feet of the surface, except in areas of coarse granular materials. The area straddles the western boundary of the Canadian Shield which is shown on present geologic maps as reaching the coast at the southern end of Darnley Bay just east of the mouth of Brock River. In reality, the boundary should be shifted to the northeast because there is an area of Tertiary (?) sediments which are exposed northeast of Brock River and outcrop in an area of over 100 square miles. 5 The entire region was glaciated, and morainic material blankets most of the bedrock within 30 to 40 miles of Darnley Bay (excluding Parry Peninsula) but large areas of bedrock are exposed at the surface farther inland. Evidences for two directions of ice movement approximately at ?Based on field investigations carried out for the Geographical Branch, Department of Mines and Technical Surveys, Ottowa, with whose permission this paper is published. Thanks are due to Keith Fraser for his assistance in the field. 18 Yearbook of the Association Vol. 15 CAPE PARRY MILES Figure 1. Map of Darnley Bay area showing glacial lineatlon in ground moraine and bedrock with inset map to show general location 1953 of Pacific Coast Geographers 19 ,CAPE PARRY FRANKLIN BAY DARNLEY BAY CHANNEL A IIIBIIIIH.Î*·M >» MILES Figure 2. Map showing the principal post-glacial drainage channels. Dashed boundaries have been used to delimit drainage channels about which there is some uncertainty. 20Yearbook of the AssociationVol. 15 right angles to each other occur in the terrain. A general east-west trend is apparent across Parry Peninsula changing to a northeastsouthwest trend on the east side of Darnley Bay. This movement coincides with that of no known ice center. The other principal direction is found south and southeast of Darnley Bay where the ice moved from south to north, with a westerly component. This direction is a continuation of the projected trend from the Great Bear Lake area. Poet-Glacial Stream Capture As déglaciation progressed, the streams followed in general the regional slope of the land and drainage was in a chaotic state. It is possible to reconstruct much of the early drainage pattern from the evidences given by large, dry, abandoned valleys and also by misfit streams. The former drainage channels...

Identification of Petitot's Riviere La Ronciere-le Noury

Contains a study of explorations in the Horton and Hornaday River regions of northern Mackenzie District. Evidence is presented to suggest that the river discovered and mapped (excepting lower reaches) by the Oblate missionary Emile Petitot in 1868 is identical with the Hornaday. The latter, discovered by A.J. Stone in 1900 was explored only near its effluence into Darnley Bay. Recent mapping from aerial photographs show the source of the Hornaday (68 40 N, 120 20 W) and features of its course as similar to those recorded for La Ronciere-le Noury by Petitot in his Geographie de l'Athabaskaw-Mackenzie...1875.(Arctic Bibliography, No. 13406).