Ecological Land Classification of Mount Revelstoke and Glacie r ...

Massive, highly resistant lithologies, mainly quartzite, within the Hamill and granitic intrusive rock sproduce the most rugged topography in MRNP and GNP (Plate 1) . Massive, precipitous, mountai npeaks and narrow, craggy, serrated ridges are abundant with most peaks >2700 m . Several peaks inthe Hermit, Sir Donald, Dawson, Bishops, and Purity Ranges are 3200 m. The highest peaks are :Mount Dawson, consisting of Hasler Peak (3390 m), Mount Selwyn (3360 m), Feuz Peak (3350 m )and Michel Peak (3077 m) ; Mount Wheeler (3363 m); and Mount Sir Donald (3297 m) . Long, connectingridges are uncommon except around the northwestern boundary. Well defined cirques areabundant, particularly on northerly and easterly aspects . Glaciers and icefields occur extensively inthe highest areas. Deeply incised, narrow, glaciated valleys separate most mountain ranges . Thesehave very steep walls that often include craggy and gullied portions . Internal relief is frequently 1500m but ranges from 1000 m above low passes to nearly 2250 m between Mount Sir Donald and th eBeaver River. Vegetated landscape occupies a significantly greater proportion of this relief than doesunvegetated terrain, except in areas of high peaks and extensive glaciers .Recessive slate and schist bedrock of the Lardeau Group occupies a small area along the southwester nboundary of GNP (Plate 2) . The topography is similar to the Purcells in eastern GNP but valle ywalls are steeper and longer, internal relief is 1100 to 1800 m, and some have craggy sections . Thehighest elevations (Corbin Peak, 2712 m) occur along the connecting ridges that form the southwest -ern park boundary . Most of the vertical relief is vegetated . The mountain ridges are steeper and narrowerthan in the Purcells and well defined cirque valleys extend north and east from the main ridges .Current glaciers are few and very small .A great variety of metamorphic and granitic rocks of the Shuswap Metamorphic Complex characterizesMRNP . Thus, the variety of resistances to erosion gives more than one kind of topography .One type, occurring in Clachnacudainn Creek-Inverness Peaks and West Woolsey Creek areas, re -sembles the rugged topography of the Hamill area in GNP, in having narrow valleys with long, steep ,often craggy walls culminating in precipitous, cliffy, narrow ridge and mountain tops . A second ,more extensive ty of topography occurs in the vicinity of Mount Revelstoke . Narrow valley floors(e.g. Illecillewaet) are bounded by long, steep slopes which grade at about mid-slope (1500-1900 m )to broad, rounded, hummocky or ridged, plateau-like shoulders or cirques. Small isolated peaks ornarrow mountain ridges, well back from the valley wall, complete the profile . Valleys in MRNP aredeeply incised and narrow with little benchland along floors . Vertical relief of >1800 m is commo nalong the Illecillewaet and Columbia rivers . The maximum range is Revelstoke townsite (456 m) toMount Revelstoke summit (1938 m), and to Mount Coursier, the highest peak in MRNP (2646 m) .Most of this vertical relief is vegetated . Glaciers are extensive in MRNP, the largest occurring on thenortheast side of Inverness Peaks and Mount Coursier .DRAINAGE SYSTEMSMRNP and GNP occur within the Columbia Initial Drainage Division (Shera and Grant 1980), als ocalled the Columbia Basin . MRNP and GNP drain via the Columbia and Illecillewaet Major RiverWatersheds (Shera and Grant 1980) . The Beaver River, flowing north to the Columbia River, drain sthe eastern and northern parts of GNP . Main tributaries in east-central GNP are Connaught, Grizzly,East Grizzly, and Copperstain creeks . The largest tributary, Mountain Creek, and its tributarie sdrain the northwestern quarter of GNP .The Illecillewaet River and tributaries drain the central and southwestern portion of GNP and themajority of MRNP . Major tributaries of the Illecillewaet River in GNP include Bostock and Flatcreeks, and Asulkan, Cougar, and Loop brooks. Major tributaries of the Illecillewaet River i nMRNP include Maunder, West Woolsey, Woolsey, Clachnacudainn, Bridge, and Hamilton creeks. Al lare part of the Illecillewaet Major River Watershed which empties into the Columbia River at Revel -stoke townsite . Coursier and St. Cyr creeks and other smaller tributaries on the western side o fMRNP drain directly into the Columbia River .The Incomappleux River and tributaries drain the south central and southern portion of GNP . Majortributaries in GNP include Van Home and Bain brooks and Mitre and Black creeks .Very few lakes occur in GNP . The only named lakes are Schuss Lake on Mount Fidelity and MarionLake above Glacier station. A notable unnamed lake occurs at the mouth of Glacier Circle . Othe rsmall unnamed lakes and ponds occur in backwater localities along the Beaver River and MountainCreek .3