SUGAR ICEBERG: (II.A.5.a.) — An iceberg composed of the most 

 porous type of glacier ice. Such ice is formed at very low temperatures, 

 is loosely constructed, and falls apart easily. See iceberg. 



TABULAR ICEBERG: (II.A.5.a.)— A mass of ice calved from shelf ice, 

 with a flat upper surface and with at least the upper portion formed 

 from a stratified snow or neve. A pronounced feature of the weather- 

 ing of tabular icebergs, whether by atmospheric agents or by sea 

 water, is the change in color from the original dazzling white to an 

 equally beautiful blue. See iceberg. (Figs. 94-96.) 



TALUS: (II.B.) — A heap of coarse rock waste at the foot of a cliff, or 

 a sheet of waste covering a slope below a cliff. Scree is the term more 

 commonly used in Great Britain, whereas talus is more commonly used 

 in the United States. Talus slopes are very common in the more rugged 

 parts of the arctic. (Frontispiece.) 



TARN: (II.B.) — A small mountain lake or pool. 



TELESCOPED ICE: (I. A. 4b.)— Rafted ice. 



TENSION CRACK: (I.C.l.a.)— Strain crack. 



TENTED ICE: (I.A.4.f.) — A type of pressure ice created in an area of 

 consolidated ice when ice is displaced vertically upward forming a 

 flat-sided arch and thus a cavity between the tented ice and the 

 sea water surface. See pressure ice. 



TERMINAL MORAINE: (II.B.)— Deposits of debris in front of or at the 

 snout of a glacier. 



THROUGH GLACIER: (II.A.2.)— A glacier heading on a low, flat 

 divide from which ice streams flow in opposite directions. Such a 

 glacier is said to be double-ended. 



TIDAL PLATFORM ICE FOOT: (I.B.l.a.)— An ice foot produced 

 between high and low water levels by the rise and fall of the tide. 



TIDE CRACK: (I.C.l.a.) — A crack in sea ice, usually parallel to the 

 shore, caused by the rising and falling tide. It thus separates the moving 

 ice from the ice foot. Several such cracks frequently occur as a family. 



TIDEWATER GLACIER: (II.A.2.b.)— A glacier that descends into 

 the sea, where parts of it may break off to form icebergs. 



TILTED ICEBERG: (II.A.5.a.)— A tabular iceberg that has become 

 unbalanced, so that the flat, level top is inclined. See iceberg. (Fig. 91.) 



TONGUE: (I.A.l.f.) — A projection of floating ice caused by wind and 

 current. The extent of a tongue may be several miles. Cf. belt, patch. 



TOPOGRAPHY (of ice) : (I. A .4.) — The degree of surface roughness, 

 from flat to extremely rough. The terms most frequently used (some- 

 times in combination) to describe the topography of ice are: Flat, 

 rafted, ridged, hummocked, weathered, and puddled. See pres- 

 sure ice. 



TORSION CRACK: (I.C.l.a.) — A crack produced in sea ice by two 



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