Guide books of excursions in Canada1-10 . they are also developed in places in the graniticintrusives. Particular Description. Topographically, the main feature of the district, isthe great valley of Lewes river. Opposite Whitehorse thevalley has a width from base to base of the enclosing hills,of fully 4 miles (6-4 km.) It is bordered on the east byCanyon mountain, a long symmetrical limestone ridgerising to a height of 2,500 feet (760 m.) above the valleybottom, and 4,730 feet (1,438 m.) above the sea. Thewestern boundary is more broken, and consists, fromsouth to north, of Golden Horn, a pr
Guide books of excursions in Canada1-10 . they are also developed in places in the graniticintrusives. Particular Description. Topographically, the main feature of the district, isthe great valley of Lewes river. Opposite Whitehorse thevalley has a width from base to base of the enclosing hills,of fully 4 miles (6-4 km.) It is bordered on the east byCanyon mountain, a long symmetrical limestone ridgerising to a height of 2,500 feet (760 m.) above the valleybottom, and 4,730 feet (1,438 m.) above the sea. Thewestern boundary is more broken, and consists, fromsouth to north, of Golden Horn, a prominent peak 5,400feet (1,542 m.) in height; a wide irregular ridge culminatingin Mount Mclntyre, 5,200 feet (1,581 m.); and MountHaeckel, 5,318 feet (1,617 m.) in height. These elevationsare separated by wide drift-filled depressions, extendingacross the range. *The descriptions here given of the Whitehorse Copper belt are mainly summarizedfrom Mr. McConnells report on the district [59], supplemented by recent observationsby the 73 The central portion of the old pre-glacial valley isfloored with silts and boulder clays, and through thesethe Lewes has cut the narrow, winding, secondary valley,about 200 feet (61 m.) in width, in which it now flows. The oldest rocks known in the district are limestones,which are referred to the Carboniferous. These have beenbroken through and largely destroyed by three distinctigneous invasions. The earliest invasion was by andesitesof various kinds. These were intruded, partly at least, inthe form of sheets or sills up to 1,000 feet (304 m.) or morein thickness. The second invasion is represented byplutonic rocks, which range in mineralogical compositionfrom hornblende granites to augite syenites, diorites,and even to gabbros. These rocks cover a large portionof the district and may represent an outlier of the CoastRange batholith. The third period of igneous activityresulted in the production of the numerous porphyritedikes now found c
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectgeology, bookyear1913
