Landforms of British Columbia 1976 - Department of Geography

Lineation-in rock the parallel orientation of structural features that are lines rather
than planes. It may be expressed by the parallel orientation of the long diiensions
of minerals or of pebbles, cleavage-bedding intersections, or fold axes.
Lowland-includes the extensive plains or country lying not far above sea-level,
in general less than 1,000 feet altitude, but marked off by their contrast with
the higher lands of the mountains rather than by any special altitude. The
surface may be undulating or hilly. See Plate VIIB.
Matterhorn-a sharp horn-like or pyramid-shaped mountain peak somewhat re
sembling the Swiss peak of that name. It is a product of erosion by cirque
glaciers. See Plates XLIB and XII&
Mature-a stage in the cycle of erosion, between youth and old age, when stream
have reached a gentle gradient and valleys are wide and deep.
M&water-water resulting from the melting of snow or of glacial ice.
Metamorphism-the mineralogical and structural adjustment brought about in solid
rocks by changes in physical and chemical conditions.
Monadnock-by long continued erosion a land surface may be reduced to an almost
level plain, but there still may be a few hills or mountains which, having
escaped final destruction, still rise conspicuously above the plain-these
monadnocks. See Plate XXIVB.
are
Moraine-an accumulation of drift, built chiefly by the direct action of glacier ice.
Nun&k--a hill or peak which was formerly surrounded but not overridden by
glacial ice; one which now projects through the surface of a glacier. See Plate
XLIA.
Orogeny-the process of forming mountains by folding and faulting.
Outwash-stratified drift deposited by meltwater streams beyond active glacier ice.
Outwash plain-the surface of a broad body of outwash. See Plate XLIA.
Overthrust-a thrust fault with low dip and a large displacement that is generally
measured in miles.
Peneplain-a land surface worn down by erosion to a nearly flat or undulating
plain.
Physiography-originally, the systematic examination of landforms and their genetic
interoretation. This meanine is now conveved bv eeomoroholoav. and ohvsiograpLy
is considered to in&de
geomorphology.
climatol&y ahi oce&ogra& as weil as
Piedmont-lying or formed at the base of mountains, as a Piedmont glacier.
Piracy-the diversion of the upper part of a stream by the headward growth of
another stream, also called stream capture, stream robbery, and beheading.
Plain-an area of level or nearly level land. See Plates VA and XLVIIB.
Plateau-an elevated area of comparatively flat land which may be partly dissected
by valleys. See Plate XXXVIII.
Prairie-a treeless and grassy plain. See Plate XXXIXB.
Pro-glacial lakea lake of glacial origin lying beyond the ice front.
Pyroclastic--a general term applied to volcanic materials that have been explosively
ejected from a volcanic vent.
Range-a chain of mountains or hills.
,
Rejuvenate-to stimulate, as by uplift, to renew erosive activity; said of streams.
Relief-the difference in elevation between the high and low points of a land surface.
Roche moutonn&--a rounded hummock or boss of rock smoothed and striated by
glacial action.
Scarp-an escarpment, cliff, or steep slope of some extent along the, margin of a
plateau, terrace, or bench. See Plate XXXVIII.
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