Landforms of British Columbia 1976 - Department of Geography

APPENDIX B.-GLOSSARY *
Aggrade-to build up by the deposition of material in a stream bed. See Plate 11~.
Antecedent-streams that are not diverted by structures which grow athwart their
course are said to be antecedent; that is, they are antecedent to the uplift.
See Plate XLIV.4.
Anticline-an arch-like fold of bedded or layered rock.
A&e-an acute and rugged crest of a ridge or of a mountain spur such as that
between two cirques. See Plates I and IX.
Basin-tie drainage area of a large river and its tributaries.
Batholith-a body of intrusive rock more than 40 square miles in extent.
Bed-a small division of layered sedimentary rocks marked by a more or less well-
defined divisional plane from its neighbours above and below.
Breccia-a rock consisting of angular fragments cemented together. The pebbles
of a conglomerate are water-worn.
Breccia pipe-a vertical or highly inclined lenticular, oval or round opening in rocks
that has been filled by angular rock fragments.
Cinder cone-a conical elevation formed by the accumulation of volcanic ash or
clinker-like material around a volcanic vent. See Plate VIA.
Cique-a deep steep-walled amphitheatre-like recess in a mountain caused by
glacial erosion. See Plate XXIXB.
Coastal plain-a plain which has its margin on the shore of the sea and represents
a strip of recently emerged sea bottom. See Plate IV.
Col-a low pass or saddle on the divide between two drainage systems.
Contour line-an imaginary line on the ground, every point of which is at the same
elevation.
Cordillera-the great mountain region of western North America between the
Interior Plains and the Pacific Ocean.
Cuesta-a gently sloping structural plain terminated on one side by an abrupt slope
or scarp.
Dip-the angle of inclination from the horizontal of a stratum or any planar feature.
Dissection-the work of erosion that destroys the continuity of an even surface by
cutting ravines or valleys into it. When the dissection is complete, no rem-
nants of the original surface remain.
Drift-any rock material, such as boulders, till, gravel, sand, or clay, transported
by a glacier and deposited directly by it or deposited by or in water derived
from the melting of glacier ice.
Drumlin-an elongate or oval hill of glacial drift whose long axis is parallel to the
direction of flow of a former glacier. See Plate XXV.
Dyke-a tabular body of igneous rock that cuts across other rocks.
Erosion surface-a land surface produced by erosion rather than by deposition.
See Plates XVB and XXXVIII.
Esker-a narrow sinuous ridge of gravelly or sandy stratified drift deposited by a
stream in association with glacier ice. See Plate XVA.
Eustatic-pertaining to simultaneous, world-wide changes in sea-level.
Fault-a fracture or fracture zone along which there has been displacement of the
two sides relative to each other.
Fiord-an inlet resulting from the sea entering a deeply excavated glacial trough
after the melting away of the glacier. See Plate XLVIa.
l Definitions ,arge,y adapted from “ Glossary Of GeOLOgy; .4me,iron Geob&-kol rnslltutc, ,957.
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