The Cassiar Mountains
Introduction
Topography
Dease Plateau Dease Lake, BC
Stikine Ranges Eve Cone Mount Edziza Provincial Park Mount Ash, BC 2 125m
Ketchika Ranges Muskwa- Ketchika Management Area
Sifton Ranges Sentinel Range, BC
Weather and Climate
Physiographic Regions
Mean Annual Temperature
January Mean Temperature July Mean Temperature
Mean Annual Precipitation
Mean Annual Snowfall
Dease Lake
Watson Lake
Hydrology
Ocean Drainage Basins of Canada
Glacial Influence on British Columbian Rivers
Monthly River Discharge
Geology
Formation of the Cassiar Mountains Collision of the Intermontane Superterrane and the North American continental plate The rocks of the Superterrane were squeezed and compressed to form the Cassiar Mountains
Mineral Exploration Asbestos Mining in Cassiar Nephrite Jade Mine Numerous gold exploration projects ongoing in the Dease Lake Region
Cassiar, BC The town closed in 1992 after the asbestos mine ceased operation after operating since the early 1950s.
Jade City, BC Dynasty mine produces approximately 90% of the world s jade Nephrite jade is a type of actinolite amphibole
Dease Lake, BC Home to gold mining and prospecting since the Gold Rush Many exploration projects ongoing in the area
Geomorphology
Glacial Movement Glaciers flowed off of the mountain range in three directions: to the northeast into the Rocky Mountain Trench; to the southeast into the Trench South of Finlay River; and to the west over the lower plateaus and uplands
Geomorphic Features from Glaciation The landscape has been scoured by glacier creating U-shaped valleys and steep cliffs with lateral moraines. Common features: cirque basins, moraines, eskers, talus slopes Currently in the paraglacial stage
Fraser Glaciation The little chronological data found tells us that the Late Wisconsin Fraser Glaciation in Southern BC is comparable to Northern BC Evidence of polythermal glaciers Main source of ice was from the central névé over the Northern Skeena Mountains
Forest Fires and Geomorphic Impact 2010 a lightening strike caused a 35,000 hectare fire by the Cassiar Highway near the Yukon border Fires change sediment movement through watersheds by changing vegetation cover and soil properties Increased mass wasting (debris flows, debris avalanche, and rapid mudflows) results from forest fire impact on the landscape
Flora and Fauna
Stone sheep, mountain goats, caribou, grizzly and black bear, grey wolf, wolverine, arctic ground squirrel
Biogeoclimatic Zones 1) The Alpine Tundra Zone- highest elevations 2) Spruce-Willow-Birch Zone- subalpine elevations 3) Boreal White and Black Spruce Zone- lower elevations and valley bottoms
Biogeoclimatic Map of BC Dark brown= Alpine Tundra Yellow/green= Spruce-Willow-Birch Blue= Boreal White And Black Spruce
Alpine Tundra - Long, cold winters with a brief growing season - Vegetation grows close to the ground - Common species include: alpine grasses, dwarf willows and lichen
Spruce-Willow-Birch Zone Common species: white spruce, subalpine fur, Greyleaved willow, Barclay s willow, tea-leaved willow, and Barratt s willow Most severe weather of all forested areas in BC Lower elevations are forest and upper elevations are scrub/parkland
Boreal White and Black Spruce Zone 10% of BC s total area Wildfires occur frequently in this zone Divided into two regions: forested area and muskeg Forested area: white spruce, trembling aspen, lodgepole pine, black spruce, balsam poplar, tamarack, subalpine fir, common paper birch, and Alaska paper birch Muskeg: Trees that occur here are stunted black spruce and tamarak. There are deep layers of peat and permafrost found under the muskeg
End