Sault Plat River

River in Quebec, Canada
Sault Plat River is located in Quebec
Sault Plat River
LocationCountryCanadaProvinceQuebecRegionCôte-NordRCMMinganiePhysical characteristicsSource  • elevation244 metres (801 ft) 2nd sourceLake Delaunay • elevation148 metres (486 ft) MouthGulf of Saint Lawrence
 • coordinates
50°17′34″N 65°26′35″W / 50.292778°N 65.443056°W / 50.292778; -65.443056
 • elevation
0 metres (0 ft)Length34 kilometres (21 mi)[3]Basin size93.1 square kilometres (35.9 sq mi)Discharge  • locationMouth • average3.8 cubic metres per second (130 cu ft/s) • minimum0.8 cubic metres per second (28 cu ft/s) • maximum9.2 cubic metres per second (320 cu ft/s) Basin featuresTributaries  • left(upstream) 5 streams, discharge from one lake (via Lac Tête de Loon, discharge from two lakes. • right(upstream) Discharge of a dozen lakes, stream (via Lac Tête de Loon).

The Sault Plat River (French: Rivière du Sault Plat) flows north/south on the north shore of the Gulf of St. Lawrence, in Sept-Rivières and Minganie RCM, in Côte-Nord region, Quebec, Canada.[4] Part of the river is located in the municipality of Rivière-au-Tonnerre, and is visible from The Whale Route (138).

Toponymy

The toponym "Rivière du Sault Plat" was made official on December 5, 1968 in the place name bank of the Commission de toponymie du Québec.[5]

The name first appeared officially on a map in 1969 in the Répertoire géographique du Québec.[6] The river was not named on 1913 & 1927 maps by Gustave Rinfret or Edgar Rochette (1890-1953).[7]

Geology and geomorphology

The rocks of the river show furrows of glacial erosion.[2][1][8]

The Sault Plat River flows in a trough-like shape carved into the rock of the Canadian Shield by the passage of glaciers during the last glaciation.The erosion marks due to the mechanical abrasion of the ice, the grooves, are up to 5 metres wide, the depth generally corresponds to a third of the width. The elongation of the groove corresponds to the direction of the glacial flow some 18,000 years ago.

The bedrock of the area belongs to the Grenville Geological Province. This 34 km long river flows over eye-eyed granite orthogneiss.[3][1]

Located to the west of Minganie RCM, the Sault Plat watershed is bordered to the east by the Tortue River watershed and to the west by the Bouleau River watershed. It covers an area of 93 km2.

The Sault Plat River empties into the Gulf of St. Lawrence at 50°17'34" N and 65°26'35" W, 50 km west of the village of Rivière-au-Tonnerre and 70 km east of the city of Sept-Îles.[4]

Soil and subsoil

On the edge of the Gulf of St. Lawrence, the coastal plain area is 5 km wide. It is characterized by an escarpment of nearly 100 m of difference in altitude by the sea and by a relatively flat plateau gradually rising to an altitude of 150 m at its northern limit.

Upstream, with an average altitude of up to 300 m, the piedmont zone divides the dominant physiography and corresponds to the rest of the catchment area. At the northern end of the watershed, rounded rocky hills rising to 533 make up the relief.[9]

The subsoil of the watershed is composed of magmatic rocks, mostly an assemblage of undeformed granite and pegmatite. A band of migmatite more than 5 km wide crosses the basin from east to west in its center. The bedrock is covered only by a thin layer of discontinuous glacial deposits not exceeding a thickness of 1 m. The coastal fringe is characterized by the regression and transgression of the Goldthwait Sea, which has left a large amount of marine clay and silt sediments covered by deltaic sandy sediments. A series of giant glacial grooves located on the bed of the river near the mouth and visible from the Route des Baleines (138) is listed as an exceptional geological site.[8]

Hydrology

Gulf of St. Lawrence, mouth of the Sault Plat River,[5] coastal shore

Entirely located in the Minganie RCM, the Sault Plat River watershed includes three major lakes.[10]
Lake Delaunay, located in the centre of the watershed, occupies an old glacial valley in a "U" shape and has a very elongated shape in the north/south axis (8 km long by a few hundred metres wide, for an area of 3.06 km2).

See also

References

  1. ^ a b c Ghismond Martineau; André Tremblay; André Brazeau (August 2009). "Geological heritage - The glacial grooves of the Sault Plat River" (PDF) (in French). Ministère de l'Énergie et des Ressources naturelles - Gouvernement du Québec. Retrieved 31 May 2024. The passage of the ice cap has left a wide variety of erosion shapes and marks.
  2. ^ a b Ghismond Martineau (12 October 2021). "The glacial grooves of the Sault Plat River" (PDF) (in French). Ministry of Energy and Natural Resources - Government of Quebec. p. 21. Retrieved 31 May 2024. Geological heritage is the Memory of the Earth, inscribed in the depths of its soil and on its surface, in landscapes, rocks, minerals, fossils
  3. ^ a b "Sault Plat River, toponymy". Gouvernement of Quebec (in French). Commission de Toponymy Quebec. 1968-12-05. Retrieved 3 June 2024. From Delaunay Lake, its source, to the falls, it follows a gentle terrain on the edge of the Laurentian plateau.
  4. ^ a b Philippe Bourdon; Ghassen Ibrahim; Myriam Luce; N’Binkéna Nantob-Bikatui; Clara Othoniel; Yohann Tremblay (14 April 2015). "Minganie Study Area, Detailed Portrait of the Sault Plat Watershed" (PDF) (in French). Duplessis Watershed Organization (OBV) Duplessis. pp. 113 of 250. Retrieved 10 June 2024. Minganie study area, Detailed portrait of the Sault Plat watershed
  5. ^ a b "Rivière du Sault Plat". Quebec Gouvernement (in French). Commission de Toponymy Quebec. 5 December 1968. Retrieved 11 June 2024. A watercourse located about fifty kilometres east of the Moisie River, on the North Shore
  6. ^ Gilbert Maistre (1969). "Quebec Ministry of Lands and Forests". Erudit (in French). Department of Geography, University of Quebec, Constituent Assembly of Montreal. p. 701. Retrieved 11 June 2024. A review of the journal Revue d'histoire de l'Amérique française, the original work is not available online
  7. ^ Edgar Rochette (February 1927). "Notes on the North Shore of the Lower St. Lawrence and Canadian Labrador". pp. 73 of 138. Nomenclature and description of the rivers of the North Shore—their distance—characteristic features—hydraulic power—Forest wealth and species.
  8. ^ a b "Exceptional geological sites" (PDF). Gouvernement of Quebec. Natural Resources and Forests. July 2005. Retrieved 12 June 2024. Jewels of Quebec's geological heritage
  9. ^ "Portrait of the Sault Plat watershed" (PDF). Duplessis Watershed Organization (in French). OBV Duplessis, Minganie. 16 October 2015. p. 6. Retrieved 12 June 2024. Low impact of human activities at the scale of the catchment area; Accessibility to the exceptional geological site could be improved
  10. ^ Catherine Simard-Côté (10 April 2024). "Regional plan for wetlands and bodies of water of the MRC de Minganie" (PDF) (in French). Land Use Planning and Development Department of the MRC de Minganie. p. 316. Retrieved 13 June 2024. The territory of Minganie covers a land area of 55,355.47 km2 and a total area of 92,546.05 km2

External links

Wikimedia Commons has media related to Rivière du Sault Plat.
  • Ecological Framework of Canada, the Taiga Shield Ecozone
  • The Saint Lawrence Its Basin & Border-Lands, 1905, Dr. S. E. Dawson, 584 p.
  • Municipalité de Rivière-au-Tonnerre, Official website (French), 2024
  • Search Results for Rivière du Sault Plat, The Canadian Geographical Names Database 6 June 2024